AR15 Platform : which caliber for a "do-it-all" (almost) purpose rifle ?

[Jager66]

Looking for an AR to use for target shooting and hunting deer as well.
Calibers I am looking into would be 223/5.56/Wylde - 6,5 Grendel - 6,8 SPC.
My intention is to go with a 20" barrel length.
Could you Guys tell me pro's and con's of these calibers and which one you would pick and why ?

I know there are better calibers out there for long range (260 Rem - 6,5 Creedmor - 7-08 Rem - 308 Win) but I'd like not to move up to AR-10....

Looking forward to your valuable help.

Thanks
J66

 

[Delta4-3]

I like 6x45. uses cheap brass, standard 30rd mags, standard bolt face, so on and so forth. There are a ton of great bullets for it, and reloading requires no extra steps, just run .223 brass into a 6x45 sizer. Outstanding performance on game, pretty good long-ish range ballistics... the list goes on.
However, this topic will get a lot of different replies because everyone has a pet AR round that is better than the next guys.

 

[BoilerUP]

AR15 Platform : which caliber for a "do-it-all" (almost) purpose rifle ?

I've been kicking around a 20" 6x45 myself...

Can one run 90gr Berger BTs at mag length in a 6x45?

I've seen the 87 Amax doesn't typically do well at AR mag length and I'm not terribly impressed with the 87HPBT relative to a 5.56/77gr combo.

 

[Ando]

Really only 6.5 Grendel matches what you are looking for. 223 is good for medium range target and is available off the shelf. 6.8 is great for hunting and is available off the shelf, but falls off too much at mid range. I've got a 6.5 br but it requires a ton of work to get going and has a limited mag capacity, but its great for hunting and target.

Grendel is available match and hunting off the shelf and is reasonably priced and capable enough to really do it all.

I wish there was a widely available saami 6mm/6.8 cased round. maximum case capacity in a double stack mag, with enough space to run the best long heavy 6mm bullets, with enough power to move the 243 bullet.

 

[Headquarterz]

I will add that the 6.5 grendel speer TNT factory Alexander arms ammo is very accurate for a production round. Should put em down as well.

 

[346ci]

6.8 is a easy choice with lots of support for brass, bullets and powder. Hell, there are several new wildcat calibers that start with 6.8 brass. It doesn't need a 20" barrel to perform but if you are looking for the most velocity and long range target shooting, go for it. When the stamp comes back, my main deer rifle will be a suppressed 12.5" 6.8.

Other than the 6.8, look at the .264LBC/6.5G. While it can kill deer also, it really shines when shooting LR. I had a .264gARP for a while but sold it to fund a 6.5CM Savage.

 

[346ci]

I wish there was a widely available saami 6mm/6.8 cased round. maximum case capacity in a double stack mag, with enough space to run the best long heavy 6mm bullets, with enough power to move the 243 bullet.

Though not widely available, BHW makes the 6X6.8, Greg and Ritch has been getting some really good results with it. 6X6.8 Black Hole and the Tale of the 646 Yard Pronghorn
If I had the time for wildcats, I'd be all over one using the 6.8 case.

 

[LRRPF52]

6.5 Grendel is the most versatile performer in the AR15 currently, if we're talking about factory-available ammunition and not having to work with a wildcat.

There is also one factory load for it that you can use for both hunting and target-shooting, and that is the 123gr Hornady SST with a .510 BC.

You could also consider a 16" or 18" barrel if you want a shorter gun. If there was one AR15 out of all mine that I was to grab for going into the unknown, it would be my 16" 6.5 Grendel.

The Grendel has been used to take pronghorn out to 752yds with a 22" barrel. Elk at 405yds with a 20" barrel (120gr TSX), Alaskan caribou out to 400yds with an 18" barrel (factory 123gr SST load), in addition to hundreds of other medium game like deer and hogs, as well as coyotes.

You have an optimum bullet weight, BC, and recoil combination with the Grendel, so that kids can even shoot it without fatigue. The 123gr .510 pills buck the wind extremely well, and retain a lot of energy as the distances increase.

 

[Jager66]

Thank you All.
It seems that Grendel would be the way to go.
I've tried to gather some information on it and it appears "optimal" bullet weight would be in the 120-130 grs.

20" barrel length does not seem to suffer much vs. a 24" (I'd prefer the shorter..).
What rate of twist would you suggest ?

Cases available from Hornady and Lapua, correct ?
What about dies selection ?

Apologize for the multiple questions....
Thank you in advance for your help.
J66

 

[lclement]

I'm in the same boat, really eyeing the Grendel since all I would need is a new upper to get started. It would for right on the ar15 lower. All you need are a few 6.5 Grendel magazines and your set. I would keep my 556 upper for practice and plinking. The Grendel Sounds like the easiest and most economical way to achieve what your ar asking bye using the same lower which means you keep the same trigger... Same feel. The Grendel also does not have much more recoil then the 556 but does have much more energy down range and stays supersonic past 1000 yards with better BC. Sure a 338 lapua would best the best past 1000 yards but at a higher financial cost plus a heavier gun. The Grendel would keep the gun weight down which is good while hunting and stocking.

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[lclement]

As for a 20 vs 24 barrel, if I were to walk with the gun I think I would like a 20 barrel, bit if were mostly a bench gun then I would consider the 24 but probably still go 20.

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[redneckbmxer24]

What sort of target shooting are you looking to do? Any run and gun in there? If so I'd run two uppers. Depending on how far you want to shoot 5.56 may do everything you want except hunting. To hunt you could pick up a separate 6.8 upper.

The LMT MRP is also a solid option. You can change barrels at the range with just a torque wrench and POI shift is minimal (under 1MOA).

 

[lclement]

Which is better the 6.5 Grendel or 6.8? Or do they have different philosophy of uses?

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[BoilerUP]

Which is better the 6.5 Grendel or 6.8? Or do they have different philosophy of uses?

NO NUTNFANCY REFERENCES



But, yes.

 

[1slow01z71]

Id just go regular ole 223 so you can plink cheap. The 77gr loads perform just fine for medium range work. All other calibers are going be much more expensive to plink with. Once you start talking premium ammo theyre all within a couple bucks of each other.

Really boils down to how far you want to shoot.

 

[lclement]

NO NUTNFANCY REFERENCES



But, yes.

Lol! Dang it you got me there hahaha!

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[LRRPF52]

Thank you All.
It seems that Grendel would be the way to go.
I've tried to gather some information on it and it appears "optimal" bullet weight would be in the 120-130 grs.

20" barrel length does not seem to suffer much vs. a 24" (I'd prefer the shorter..).
What rate of twist would you suggest ?

Cases available from Hornady and Lapua, correct ?
What about dies selection ?

Apologize for the multiple questions....
Thank you in advance for your help.
J66

If you are living and hunting in the Northern VA area, you can use 100gr pills for closer ranges as well, but the 123gr SST will kill effectively from within 50yds on out as far as you are capable of placing the shot in the vitals. We have done theoretical discussions on optimal bullet weight for the Grendel, and I think the number "117gr" has popped up before. The 123gr SST from a 20" will cough out in the high 2400's to high 2500's.

A Grendel forum member just took a white tail deer in the mountains of Virginia this week at 370yds with a 20" Grendel pushing the 123gr SST at 2550fps, on top of CFE.

Brass is available from:

* Lapua
* Hornady
* PPU (once fired from the Wolf Gold Line loads)
* Nosler (announced at 2013 SHOT)
* 7.62x39 sized and fire-formed (there are well over a dozen sources for 7.62x39 brass, including Lapua, Remington, IMI, Winchester, Federal, PMC, PPU, S&B, etc.)

Most just use the Lapua and Hornady. Alexander Arms factory ammunition uses Lapua brass with an "Alex-A" head stamp.

Full-length sizing/de-capping dies are available from Hornady, Redding, Forster, avoid the Lee's.
Best seating dies are the competition seating units from Forster & Redding.
Shell-holder is the same as 7.62x39, .38 Special, .357 Mag, & 6mm PPC. Hornady #16, RCBS #32, Redding #12, Lee #12, Lyman #1, Dillon Shellplate #A, Pin#2

I like my 16" Grendel because I am able to get 20" velocities from it by loading the COL out longer, and using CFE223. There is a nice 20" upper for sale on the Grendel forum right now as well. (not mine)

There is also a 6.5 Grendel Reloading Handbook, along with a lot of data from the major manufacturers, including AA, Vihtavuori/Lapua, Hodgdon's, Western/Accurate Powders, and Hornady (8th & 9th Editions). Hornady's 8th Edition has 14.5" barrel data, while the 9th has 18" data.

Complete Uppers and mags are available from:

* AA
* Precision Firearms
* JP Enterprises
* J&T Distributing/Double Star
* Les Baer (.264 LBC-AR chamber, feeds factory Grendel ammo just fine)
* Templar Customs
* SAOD Industries
* Specialized Dynamics

Id just go regular ole 223 so you can plink cheap. The 77gr loads perform just fine for medium range work. All other calibers are going be much more expensive to plink with. Once you start talking premium ammo theyre all within a couple bucks of each other.

Really boils down to how far you want to shoot.

I shoot a lot of 77gr, 75gr, and 69gr throughout the year in my DM Courses. Wind deflection and retained energy are night and day compared to my 16" Grendel with the 123gr. Impact on steel is still audible in high wind conditions, whereas with the 5.56, you need a very experienced spotter to register the hit, and even then it's a toss-up.

Reloading for any of them makes for higher volume range sessions. FGMM & Hornady 68gr Match are the same price as Hornady Match Grendel. I shoot them both, but for hunting and target-shooting, it's a no-brainer in favor of the Grendel.

 

[colscar]

i have a 6.8 and took it hunting last year.... wont take it past 300 yards maybee even 250 but works good especially with 110 accubonds..... im planning on getting another ar platform in 308... i got another 308 rifle and reloading will be easy since i already have the brass and dies....

 

[BravoSierra]

.264 LBC/grendel for the win. I just stepped from the MK12/mk262 loads and into an 18" .264 ARP with adjustable gas. Less recoil, or the impulse is totally different, and the impact at 600 is clearly audible with standard hornady 123 AMAX box load, not to mention the splash from misses are much faster to pick up than the 5.56 loads. Is quickening my learning curve and my confidence is growing even on windy days now. I know there is some pretty cool 6.8's out there that can equal it at this range, but i believe those are with hand-loads.

 

[LRRPF52]

There are no production .277" pills that will mag-feed in the 6.8 SPC II that can match the .510 BC of the 123gr in the Grendel.

The closest factory load that I'm aware of is the SSA 140gr Berger VLD with a .487 G1 BC, coming out at 2400fps from a 16" barrel, which is actually pretty impressive if you think about it and compare it to .308 Winchester. It is very comparable to the 123gr in the Grendel as far as energy goes from 16" barrels, because of the 140gr vs. 123gr, although the 123gr is flatter, has less wind drift, and is faster. The 140gr SSA load is $10 more a box when in stock, but hasn't been in-stock for a while.

I would prefer the SST over a Berger on game, but the Bergers still do very well, especially in that bullet weight and lower impact speeds where the pill is less likely to come apart. A cannelure on the Berger Hunting VLD would make it very comparable to an SST.

I still don't understand why SSA didn't use the .277" 130gr VLD Classic Hunter, with a higher BC (.497), and shorter length. Maybe the ogive was too long on it for the 6.8x43 case in the AR15 magazine, and it requires a 1/10 twist. A bullet with that profile in the 6.8 SPC would be very comparable to the Grendel, but you will pay significantly more for it.

The Nosler 110gr Accubond is another great load I would use if I were trying to compete with a Grendel. It's fast, holds together beautifully, and has a fairly decent BC on it (.370). Costs are again prohibitive with it compared to the factory 123gr SST in the Grendel, but it is what it is.

There isn't a lot you can with the .277" bore other than try to keep upping the velocity with the limited space there is in the AR15, since most 140-150gr .277" pills simply won't go fast enough with the case capacity, and don't fit into the magazine.

With the Grendel, you are already into the .5's for BC with 123gr. If you need more weight, you can shoot 129's and 130's that are in the .485 to mid .5's for G1 BC. It's basically a Goldilocks cartridge in the AR15, where several parameters all align nicely:

* COL is dealt with by using a fatter, shorter case that still mag-feeds from a double column magazine
* The short case allows for a lot of ogive length, opening up high BC territory
* The pressures are set nice and low for weapon life and smooth recoil, while giving manufacturers a sigh of relief when looking at the SAAMI MAOP
* Projectile SD is high for caliber, so you retain energy well, get excellent penetration on game, and very minimal wind deflection

 

[MLC]

I'd also consider the 6mmAR.
Plenty of great target and hunting bullets.

 

[lclement]

Can you buy 6MMAR off the shelf?

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[bustin]

Can you buy 6MMAR off the shelf?

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Yes, the 6mm Hagar too.

 

[bohem]

I have what is a wildly improved version of the BHW 6x6.8 case, close to the 6 HAGAR, it's made by a guy local to me. "240 Tomahawk"


I bought some 6.8 mags, a 6.8 bolt head, and a new gas block (wasn't necessary but I bought one anyway). I'm getting 2750-2775 from the 105 Hornady, it takes fireforming but I get 1/2 minute groups fireforming, and the dies are part of the package you can order from him. He said his barrels are maintaining competitive High Master scores over 4000 rounds. An AR15 platform that can stay MOA at 600+ after 4000 rounds is a major winner to me.

I form brass with a custom die from the maker, 0.267 Redding bushing, and 1 pass through the progressive. Input Hornady 6.8 SPC brass, out pops loaded rounds ready for fireforming.

Neck down and form false shoulder - die 1
Prime
Charge
Seat bullet

Done


ETA: 22", runs through my 5.56 suppressor without an issue, and does all this burning 27.5-29.0 grains of IMR 8208 XBR, which meters fine from the Hornady thrower in the LnL AP press.

 

[Cobracutter]

For ammo availibility the 6.8 smokes the 6.5.... Less than 400yrds the SPC2 has a slight edge.... Over 400, the 6.5 starts to pull away.

Reality is, both are pretty similar and the longer u push the 6.5G, the more you should be stepping up to a .308 cased round.

Personaly, I dont reload so I would go with 6.8 SPC. Plenty of power at the muzzle, and good power out to 400-500 yards.

Be realistic how far you are going to shoot. 90% less than 300 yards like most shooters? stick with 5.56.

There is no one , do it all rifle... thats why we own so many different ones. You can shoot tiny groups at 600 yards with 5.56 cheaply, but you aint hunting shit at that distance......atleast not ethically
You can shoot 6.5G at 300 yards all day, but you will be paying out the ass.

If you have to target (IE long range over 600 yards) and HUNT, you need to step up to something bigger.... maybe even 300wm depending on size of game and range.

 

[azimutha]

I don't have any firsthand experience to report yet, but just chose to do a 6.8 build over the Grendel. The rifle is intended for hunting sub-300 yards. I'm hopeful I can get the Berger 130 CH to work well. I really like the performance of the 168gr. CH in my .308. Hard to know until you try though. I went with an ARP 16" barrel that has an 11.25 twist. Looks like the Berger 130, if seated to mag length (i.e. PRI mag length!) at 2.30" will be right at the ogive or maybe slightly into it:

 

[xNF_9]

I originally started out in the same place you were and I currently own a 6mmAR and now. The reason I really like the round is the bullet selection for target shooting and predator hunting.

Now I own a 6mmAR and would say that it is a very versatile round. I'll add another vote for the caliber. It's inherently very accurate coming from the 6PPC round which has held many records for quite some time in the accuracy department. Of course it is a 6.5 Grendel necked down to a 6mm.

 

[LRRPF52]

For ammo availibility the 6.8 smokes the 6.5.... Less than 400yrds the SPC2 has a slight edge.... Over 400, the 6.5 starts to pull away.

Reality is, both are pretty similar and the longer u push the 6.5G, the more you should be stepping up to a .308 cased round.

Personaly, I dont reload so I would go with 6.8 SPC. Plenty of power at the muzzle, and good power out to 400-500 yards.

Be realistic how far you are going to shoot. 90% less than 300 yards like most shooters? stick with 5.56.

There is no one , do it all rifle... thats why we own so many different ones. You can shoot tiny groups at 600 yards with 5.56 cheaply, but you aint hunting shit at that distance......atleast not ethically
You can shoot 6.5G at 300 yards all day, but you will be paying out the ass.

If you have to target (IE long range over 600 yards) and HUNT, you need to step up to something bigger.... maybe even 300wm depending on size of game and range.

There is no "slight edge" with the 6.8 SPC II within 400yds. Doesn't exist, and you will see that when you run the numbers. I actually used to believe it, until I ran them myself and said, "Hey. This is wrong. A 16" Grendel not only has more mv than you think, but it out-runs the relatively low-BC .277" pills rather quickly. Someone has been taking statements from other people, not doing any fact-checking, and repeating them."

Quantify these statements, and you will see that the 400yd edge gets dressed down really quick. To make my point, I will take a max hand-load in a Wilson Combat 16" 6.8 SPC II, using 27.2gr of AA2200 underneath the 120gr Hornady SST, loaded long at 2.280" COL, which averaged 2537fps.

We will compare it to the Hornady 123gr SST factory load from a 16" Grendel, which averages 2460fps for me. 6.8 SPC II max hand load, 6.5 Grendel factory load, bullet weight, construction, and manufacturer as close as you can get between the two:

6.5 Grendel, 16", Factory Hornady 123gr SST:

      Range    Velocity    Energy     Trajectory         TOF          Drift
      (yards)     (fps)     (ft-lb)     (inches)         (sec)       (inches)
          0      2460        1653          -2.50         0.0000         0.00
         25      2419        1598          -0.79         0.0307        -0.05
         50      2378        1544           0.54         0.0620        -0.19
         75      2337        1492           1.50         0.0938        -0.42
        100      2297        1441           2.05         0.1262        -0.75
        [b]125      2257        1391           2.19         0.1591        -1.19[/b]
        150      2218        1343           1.91         0.1927        -1.72
        175      2179        1296           1.18         0.2268        -2.36
        200      2140        1251           0.00         0.2615        -3.11
        225      2102        1206          -1.66         0.2969        -3.97
        [b]250      2064        1163          -3.81         0.3329        -4.94 Point Blank for 10" Vitals[/b]
        275      2026        1121          -6.47         0.3695        -6.03
        300      1989        1081          -9.65         0.4069        -7.24
        325      1953        1041         -13.39         0.4449        -8.57
        350      1916        1003         -17.70         0.4837       -10.03
        375      1881         966         -22.59         0.5232       -11.62
        400      1845         930         -28.10         0.5635       -13.34
        [b]425      1810         895         -34.25         0.6045       -15.20 Still above minimum expansion[/b]

16" 6.8 SPC II 120gr SST Hand Load 27.2gr AA2200 2.280" COL

       Range    Velocity    Energy     Trajectory         TOF          Drift
      (yards)     (fps)     (ft-lb)     (inches)         (sec)       (inches)
          0      2537        1715          -2.50         0.0000         0.00
         25      2483        1643          -0.84         0.0299        -0.06
         50      2430        1574           0.47         0.0604        -0.23
         75      2378        1507           1.41         0.0916        -0.52
        100      2326        1442           1.97         0.1235        -0.93
        [b]125      2275        1379           2.13         0.1561        -1.46[/b]
        150      2225        1319           1.86         0.1894        -2.13
        175      2175        1260           1.16         0.2235        -2.93
        200      2126        1204           0.00         0.2584        -3.86
        [b]225      2077        1150          -1.64         0.2941        -4.94  Point Blank Range for 10" Vitals[/b]
        250      2029        1097          -3.79         0.3306        -6.17
        275      1982        1047          -6.46         0.3680        -7.55
        300      1936         998          -9.69         0.4063        -9.09
        325      1890         952         -13.49         0.4455       -10.79
        350      1845         907         -17.90         0.4856       -12.65
        375      1800         864         -22.96         0.5268       -14.69
        400      1757         822         -28.68         0.5690       -16.92
        425      1714         783         -35.10         0.6122       -19.32

I can break out my hand loads for the 123gr SST, where one 3 steps down from before seeing any pressure signs is 2572fps. Then someone will show up with a 6.8 SPC 110gr Accubond at 2800fps with a super bolt, loaded to 2.310" in a PRI magazine, saying..."The primers still look ok!" It will be madness!

 

[Regalkismet]

We get it... You love the 6.5 and regularly bring your manipulated numbers to the table every chance you get.... I think every one here can look up data on loaded 6.5 and 6.8 SPC II Ammunition and figure out which has more velocity.... Get over the 6.5 vs 6.8 crap.... It's way old and over done.... Both are great rounds. I've had this discussion with you in the past and won't get mired in the bs any further.... Your ballistic info has always been incorrect when I've checked it and you always under value 6.8 spc II velocity while exaggerating 6.5 velocity. Beyond that I almost think your jealous that the 6.8 seems to have more wide spread industry support and availability of components... That said I do hope the Grendel receives just as much support as its a great round as well but this seems to me to be more about your business as you are clearly involved financially with the 6.5.

 

[LRRPF52]

We get it... You love the 6.5 and regularly bring your manipulated numbers to the table every chance you get.... Get over the 6.5 vs 6.8 crap.... It's way old and over done.... Both are great rounds.

Correct. I manipulated the numbers in favor of the 6.8 to try to make the Grendel look bad, and I failed. If someone is going to say the 6.8 SPC has a slight edge over the Grendel within 400yds when the OP asks about performance comparisons, I'll probably be one of the first to speak up, and I agree that both are great cartridges.

The 120gr SST and 110gr Accubond are some of the best loads for the 6.8 SPC for hunting reach. In many ways, you could call it pole-vaulting over mouse turds within 225yds, where most hunters will be shooting medium game anyway. However, the real proof is in the number of reported hunts we are seeing where deer and even larger game are regularly being taken cleanly from 370yds out to 500yds. This is a real consideration for the new consumer in the High Performance Intermediate Cartridge market, not a tit for tat.

Allowing statements that falsely compare the two is misleading, even if done innocently, and should be addressed in a technical forum. Either the 6.8 is or isn't more effective out to 400yds than the 6.5 Grendel, and people who are just learning about the two just might want to know what kind of drift, speeds, and energy they will have at 350yds, 375yds, 400yds, etc. Would you agree with that assessment?

 

[Cold_Bore_88]

My opinion leans towards the 5.56. The Grendel and 6.8 are superior rounds (opinion), but the are more expensive and will be harder to find. The 5.56 has so many options when it comes to ammunition that everyone could fin what they want. Try have some pretty destructive 5.56 hunting rounds now.

 

[azimutha]

Regarding the ballistics for 6.5 Grendel and 6.8X43, the Grendel has the advantage at any given bullet weight since the SD will be higher for the smaller caliber. In my case, there were other factors for choosing the 6.8X43:

1) I wanted an ARP barrel and bolt and ARP no longer supplies a 6.5

2) I had great results with the Berger 168 gr. Classic Hunter in my .308 this season...that doesn't necessarily translate to another bullet of the same type. However, I've found the hybrid ogive bullets load very well...have never had to do a ladder test. They just shoot, whether from a .308 AR, a Remington 700 SS or a Tikka T3 Lite. There's a 130 gr. .277 bullet but not a .264. This is a narrow reason for choosing one over the other.

3) I won't use any AR-15 based firearm to shoot past 300 yards. At that distance, in a 20 MPH crosswind, the difference in drift is less than 2". I can't think of a single shot on game at that distance that didn't offer an opportunity to shoot prone or kneeling broadside. This is one man's opinion, but I don't believe in long-range shots on animals. I did it once and it worked fine, but the major issue is time of flight. An animal can easily move several feet if not yards in less than a second.

 

[Cobracutter]

There is no "slight edge" with the 6.8 SPC II within 400yds. Doesn't exist, and you will see that when you run the numbers. I actually used to believe it, until I ran them myself and said, "Hey. This is wrong. A 16" Grendel not only has more mv than you think, but it out-runs the relatively low-BC .277" pills rather quickly. Someone has been taking statements from other people, not doing any fact-checking, and repeating them."

Quantify these statements, and you will see that the 400yd edge gets dressed down really quick. To make my point, I will take a max hand-load in a Wilson Combat 16" 6.8 SPC II, using 27.2gr of AA2200 underneath the 120gr Hornady SST, loaded long at 2.280" COL, which averaged 2537fps.

We will compare it to the Hornady 123gr SST factory load from a 16" Grendel, which averages 2460fps for me. 6.8 SPC II max hand load, 6.5 Grendel factory load, bullet weight, construction, and manufacturer as close as you can get between the two:

6.5 Grendel, 16", Factory Hornady 123gr SST:

      Range    Velocity    Energy     Trajectory         TOF          Drift
      (yards)     (fps)     (ft-lb)     (inches)         (sec)       (inches)
          0      2460        1653          -2.50         0.0000         0.00
         25      2419        1598          -0.79         0.0307        -0.05
         50      2378        1544           0.54         0.0620        -0.19
         75      2337        1492           1.50         0.0938        -0.42
        100      2297        1441           2.05         0.1262        -0.75
        [b]125      2257        1391           2.19         0.1591        -1.19[/b]
        150      2218        1343           1.91         0.1927        -1.72
        175      2179        1296           1.18         0.2268        -2.36
        200      2140        1251           0.00         0.2615        -3.11
        225      2102        1206          -1.66         0.2969        -3.97
        [b]250      2064        1163          -3.81         0.3329        -4.94 Point Blank for 10" Vitals[/b]
        275      2026        1121          -6.47         0.3695        -6.03
        300      1989        1081          -9.65         0.4069        -7.24
        325      1953        1041         -13.39         0.4449        -8.57
        350      1916        1003         -17.70         0.4837       -10.03
        375      1881         966         -22.59         0.5232       -11.62
        400      1845         930         -28.10         0.5635       -13.34
        [b]425      1810         895         -34.25         0.6045       -15.20 Still above minimum expansion[/b]

16" 6.8 SPC II 120gr SST Hand Load 27.2gr AA2200 2.280" COL

       Range    Velocity    Energy     Trajectory         TOF          Drift
      (yards)     (fps)     (ft-lb)     (inches)         (sec)       (inches)
          0      2537        1715          -2.50         0.0000         0.00
         25      2483        1643          -0.84         0.0299        -0.06
         50      2430        1574           0.47         0.0604        -0.23
         75      2378        1507           1.41         0.0916        -0.52
        100      2326        1442           1.97         0.1235        -0.93
        [b]125      2275        1379           2.13         0.1561        -1.46[/b]
        150      2225        1319           1.86         0.1894        -2.13
        175      2175        1260           1.16         0.2235        -2.93
        200      2126        1204           0.00         0.2584        -3.86
        [b]225      2077        1150          -1.64         0.2941        -4.94  Point Blank Range for 10" Vitals[/b]
        250      2029        1097          -3.79         0.3306        -6.17
        275      1982        1047          -6.46         0.3680        -7.55
        300      1936         998          -9.69         0.4063        -9.09
        325      1890         952         -13.49         0.4455       -10.79
        350      1845         907         -17.90         0.4856       -12.65
        375      1800         864         -22.96         0.5268       -14.69
        400      1757         822         -28.68         0.5690       -16.92
        425      1714         783         -35.10         0.6122       -19.32

I can break out my hand loads for the 123gr SST, where one 3 steps down from before seeing any pressure signs is 2572fps. Then someone will show up with a 6.8 SPC 110gr Accubond at 2800fps with a super bolt, loaded to 2.310" in a PRI magazine, saying..."The primers still look ok!" It will be madness!

Understood. However we are talking about commercial ammo, not handloaded... And we are looking at a 20" barrel not 16". I agree with 6.5 has better BC pills, but its hard to find them and they are expensive. If you don't reload and dont need to shoot tiny holes at 600 yards+ (which you should really be stepping up to a .308 case like I said before) then the 6.8SPC2 is more than adaquate and the lines blur. Once you factor in the cost and availibility... it becomes and easier decision.

Had AA not been a bunch of jerk offs and allowed the 6.5 to gain traction years ago, then it might be a different case. Blame Alexander for being a greedy douche for the 6.5's shortfalls.

Personally I like the 6.5 better.....but considering all the factors, its hard to support it unless you either reload or have tons of disposable income to throw after it.

And cut LRRPF52 some leway. The dude generally knows what he is talking about. Even thought Ive been banned on barfcom years ago... I still read shit there for entertainment and the tech forums. LRRPF52 is one of the few people on that site that consitantly puts out VERY accurate and level headed info/talking points. When In doubt, I would lean towards listening to him and trusting his judgement.

 

[dragbag]

I am no 6.5Grendel or 6.8SPC expert by any means. But in my area and what I have seen on-line for prices on both headstamps the price is pretty close to the same. So cost isn't really an issue to me anyways between the two. Sure there are more offerings in 6.8 compared to the Grendel. In my limited use so far with the Grendel factory 123gr A-Max kill paper very well, and has rained hell on the few coyotes I have killed with it. I like the Grendel and I appriecate all the info that LRRPF52 shares. So my take is buy one of each!

 

[bustin]

There are no production .277" pills that will mag-feed in the 6.8 SPC II that can match the .510 BC of the 123gr in the Grendel.

The closest factory load that I'm aware of is the SSA 140gr Berger VLD with a .487 G1 BC, coming out at 2400fps from a 16" barrel, which is actually pretty impressive if you think about it and compare it to .308 Winchester. It is very comparable to the 123gr in the Grendel as far as energy goes from 16" barrels, because of the 140gr vs. 123gr, although the 123gr is flatter, has less wind drift, and is faster. The 140gr SSA load is $10 more a box when in stock, but hasn't been in-stock for a while.

I would prefer the SST over a Berger on game, but the Bergers still do very well, especially in that bullet weight and lower impact speeds where the pill is less likely to come apart. A cannelure on the Berger Hunting VLD would make it very comparable to an SST.

I still don't understand why SSA didn't use the .277" 130gr VLD Classic Hunter, with a higher BC (.497), and shorter length. Maybe the ogive was too long on it for the 6.8x43 case in the AR15 magazine, and it requires a 1/10 twist. A bullet with that profile in the 6.8 SPC would be very comparable to the Grendel, but you will pay significantly more for it.

The Nosler 110gr Accubond is another great load I would use if I were trying to compete with a Grendel. It's fast, holds together beautifully, and has a fairly decent BC on it (.370). Costs are again prohibitive with it compared to the factory 123gr SST in the Grendel, but it is what it is.

There isn't a lot you can with the .277" bore other than try to keep upping the velocity with the limited space there is in the AR15, since most 140-150gr .277" pills simply won't go fast enough with the case capacity, and don't fit into the magazine.

With the Grendel, you are already into the .5's for BC with 123gr. If you need more weight, you can shoot 129's and 130's that are in the .485 to mid .5's for G1 BC. It's basically a Goldilocks cartridge in the AR15, where several parameters all align nicely:

* COL is dealt with by using a fatter, shorter case that still mag-feeds from a double column magazine
* The short case allows for a lot of ogive length, opening up high BC territory
* The pressures are set nice and low for weapon life and smooth recoil, while giving manufacturers a sigh of relief when looking at the SAAMI MAOP
* Projectile SD is high for caliber, so you retain energy well, get excellent penetration on game, and very minimal wind deflection

The Berger 130 Hybrid(.496 BC) will fit in the mag and can be used in the 6.8. I was getting 2626-2686fps with N530, 8208 and H335 last night out of a 20"
The Bergers cost $32/100
There are a few good things about the 6.8.
SSA/Nosler makes brass along with Hornady, Federal, S&B and Remington. If you don't know Nosler purchased SSA
PRI, ASC, CPD, Lancer, Barrett and Magpul makes mags for it. Those are true manufacturers not rebranded stuff like Midway and Stoner.
Parts are much easier to find than 6.5/264 parts.
LWRC is selling once fired brass for apx $240/1000
The loads quoted in a post above aren't max loads for the 120. There are a bunch of people using fast burning powder like 2200, 1200R and LT32 with heavy bullets. They hit high pressure early and stop. You know that is kind of like using 10X with 123gr bullets in the Grendel. That resulted in a lot of broken bolts didn't it? Using powers that are better suited for the heavier bullet will produce more velocity. Powders slower than optimum will produce over 2600fps.
As far as what's normal or odd with the 6.8. PRI mags are normal and do allow loading to 2.3" if you don't like it get someone to make Grendel mags that will allow it. Magpuls Pmags allow loading to 2.32" It seems 9310 alloy bolts are pretty much standard in the 6.8 and Grendel, that can't be used as an unfair advantage point. Wilson Combat ammo can be purchased by anyone. It's avail and usable so why does it not get included in factory velocity comparisons. Because it looks too good?

 

[Regalkismet]

Listen to Bustin, he actually is one of the few that really know what the 6.8 is capable of.

 

[bohem]

The Berger 130 Hybrid(.496 BC) will fit in the mag and can be used in the 6.8. I was getting 2626-2686fps with N530, 8208 and H335 last night out of a 20"
The Bergers cost $32/100
There are a few good things about the 6.8.
SSA/Nosler makes brass along with Hornady, Federal, S&B and Remington. If you don't know Nosler purchased SSA
PRI, ASC, CPD, Lancer, Barrett and Magpul makes mags for it. Those are true manufacturers not rebranded stuff like Midway and Stoner.
Parts are much easier to find than 6.5/264 parts.
LWRC is selling once fired brass for apx $240/1000
The loads quoted in a post above aren't max loads for the 120. There are a bunch of people using fast burning powder like 2200, 1200R and LT32 with heavy bullets. They hit high pressure early and stop. You know that is kind of like using 10X with 123gr bullets in the Grendel. That resulted in a lot of broken bolts didn't it? Using powers that are better suited for the heavier bullet will produce more velocity. Powders slower than optimum will produce over 2600fps.
As far as what's normal or odd with the 6.8. PRI mags are normal and do allow loading to 2.3" if you don't like it get someone to make Grendel mags that will allow it. Magpuls Pmags allow loading to 2.32" It seems 9310 alloy bolts are pretty much standard in the 6.8 and Grendel, that can't be used as an unfair advantage point. Wilson Combat ammo can be purchased by anyone. It's avail and usable so why does it not get included in factory velocity comparisons. Because it looks too good?

All makes good sense, and another I'll add to this is that the PPC case head is borderline being too-large for safety in an a standard configuration AR15 platform. I've seen a lot of low-cycle fatigue cracked bolt lugs in 6.5's and anything based on the 6.5 case head.

The easy brass, easy mags, and phenomenal bullet selection for 6mm is what pushed my choice to the caliber I mentioned above. I have 0.5 BC bullets coming near 2800fps and they run about $18/100

The 6.8 probably has more knockdown for killing animals up close, it's a bigger bullet and there's very little you can come up with besides speed to fix that issue... the 6mm handily outruns both of the calibers being argued over.

If you're biggest focus is killing animals inside 300-350yd then I'd take the 6.8 for the sake of safety alone. I want to hit targets at distances twice that, so I went with a 6 instead.

YMMV, Bustin makes very good points about parts and brass availability.

The other choice for me was the 6 Hagar but brass is more expensive, harder to get, and loaded ammo doesn't fit in the mag anywhere near as well as the 6.8 case does.

 

[LRRPF52]

I appreciate the kind words many of you have said about me, and I enjoy a healthy discussion. Harrison, that 130gr load sounds like a winner. Is that a new product from Berger, the 130gr .277" Hybrid? I went and looked for it on their site, as I'm a big Berger fan in my .260 Remington AR10, and my .270 Winchester.

If that's a new pill for the 6.8x43, that will make a nice load for sure, in addition to the existing 110gr AB, the Barnes TTSX's, & the 120gr SST.

The Wilson Combat 110gr TSX load is listed at 2700fps from a 16" barrel, and that bullet has a BC of .323, so I used the 110gr Accubond load as a comparison because it has a BC of .370, and at the same velocity, will out-do the TSX. I want to compare the highest-BC pills at the best speeds from the 6.8, with the common factory Grendel loads. Wilson Combat is showing Out of Stock on all 3 loads, and prices are $13 more than what I pay on the shelf for 123gr Hornady Grendel loads. We both could use more available ammo for these calibers, that's for sure.

I looked at Accurate and Hodgdon's reloading data, and the AA2200 data was the fastest with the 120gr SST. Hodgdon's doesn't list any updated 6.8 SPC data that I see on their site, and the old 115gr loads are there, kinda like looking back in time 7 years. They also list maximum pressures at 53,600psi, whereas Accurate lists max pressures at 58,850psi. Accurate states the data is for both SPC and SPC II chambers. I agree that for the longer bearing surface pills, more medium-burning powders are called for.

I searched on Lancer's site for 6.8 mags, and found this on 6.8 forums:

"Regarding other calibers, the L5AWM's internal geometry and non-tilt follower has been maximized to run the 5.56X45, so it will likely not run any other caliber rounds. We've tried 5.45X39 and 6.8 and neither will run in the magazine. We have no plans to make dedicated 5.45 or 6.8 version of the L5AWM."

All my 6.5 Grendel ASC, C Products, & CPD mags will take a COL of 2.307" to 2.320", depending on the mag. A lot of people keep asking for polymer mags, but I'm not one to jump on fads. My standard GI 30rd mags worked fine in the Middle East, minus full-on dust storms, so I think the PMAG craze is more of a nice-to-have.

The Six8 PMAGs are for another receiver design than the AR15.

I got into the Grendel thinking I would only hand-load for it. Last year, I found myself shooting mostly factory 123gr A-MAX, because it was just easier and the load is great. It's affordable, even compared to 5.56 Match (often less), and is accurate, with great velocity. Then they came out with the 123gr SST. I also have had excellent accuracy from Precision Firearms factory ammunition, and I end up with Lapua brass afterwards.

This year has been more reloader-intense due to prices and availability for everybody.

 

[bustin]

I appreciate the kind words many of you have said about me, and I enjoy a healthy discussion. Harrison, that 130gr load sounds like a winner. Is that a new product from Berger, the 130gr .277" Hybrid? I went and looked for it on their site, as I'm a big Berger fan in my .260 Remington AR10, and my .270 Winchester.

If that's a new pill for the 6.8x43, that will make a nice load for sure, in addition to the existing 110gr AB, the Barnes TTSX's, & the 120gr SST.

The Wilson Combat 110gr TSX load is listed at 2700fps from a 16" barrel, and that bullet has a BC of .323, so I used the 110gr Accubond load as a comparison because it has a BC of .370, and at the same velocity, will out-do the TSX. I want to compare the highest-BC pills at the best speeds from the 6.8, with the common factory Grendel loads. Wilson Combat is showing Out of Stock on all 3 loads, and prices are $13 more than what I pay on the shelf for 123gr Hornady Grendel loads. We both could use more available ammo for these calibers, that's for sure.

I looked at Accurate and Hodgdon's reloading data, and the AA2200 data was the fastest with the 120gr SST. Hodgdon's doesn't list any updated 6.8 SPC data that I see on their site, and the old 115gr loads are there, kinda like looking back in time 7 years. They also list maximum pressures at 53,600psi, whereas Accurate lists max pressures at 58,850psi. Accurate states the data is for both SPC and SPC II chambers. I agree that for the longer bearing surface pills, more medium-burning powders are called for.

I searched on Lancer's site for 6.8 mags, and found this on 6.8 forums:



All my 6.5 Grendel ASC, C Products, & CPD mags will take a COL of 2.307" to 2.320", depending on the mag. A lot of people keep asking for polymer mags, but I'm not one to jump on fads. My standard GI 30rd mags worked fine in the Middle East, minus full-on dust storms, so I think the PMAG craze is more of a nice-to-have.

The Six8 PMAGs are for another receiver design than the AR15.

I got into the Grendel thinking I would only hand-load for it. Last year, I found myself shooting mostly factory 123gr A-MAX, because it was just easier and the load is great. It's affordable, even compared to 5.56 Match (often less), and is accurate, with great velocity. Then they came out with the 123gr SST. I also have had excellent accuracy from Precision Firearms factory ammunition, and I end up with Lapua brass afterwards.

This year has been more reloader-intense due to prices and availability for everybody.

Right the 27570 130s (BC .496)are the new ones designed by Litz, they are a hybrid design. The VLD Classic hunter were the ones we asked Steckler to design a few years ago.
When the older VLDs first came out they were too long but I think they must have shortened them because at 2.3 the ogive is out side the case. Either one will work in a 6.8 but I think the hybrid will be easier to tune. All of the bullets Litz is designing now are hybrids, seems like he is reworking all of the bullet weights one at a time.
LWRC designed a new receiver set and asked Mag Pul to make mags just for the 6.8. They allow loading the 6.8 to 2.32". LWRC will sell the receivers and mags as parts for builders. They are trying to organize a group buy now. By 2015 we should have larger receivers for the 6.8 and receivers for the Nexgen 308s.
C Products Grendel mags were made by ASC, it's the same manufacturer. C Products does not exist now it split into CPD and ASC. So there are really 2 companies making Grendel mags, ASC and CPD. If Bill A had made a receiver set for the Grendel 7 years ago it would be a different ball game right now. We all know now what should have been done, hindsight is 20:20.
When I started thinking about making barrels for the Grendel/264 I checked Hornadys 123 Amax ammo in my 6.5 Banshee chamber that I designed in 07. The Amax bullet was .010 off the lands. I designed the chamber for the Lapua but couldn't have been luckier with how Hornady manufactured their ammo 5 years later. Out of the box ammo will shoot under 1/2 MOA. That's pretty tough to find from production ammo and production barrels. It's a good load but I still like the 100TTSX for hunting.
Both the 6.5 and 6.8 are fine cartridges. People bickering back and forth for 8 years is because the ones doing it don't really know what the other cartridge is capable of doing. They figure it out and stop but there is a new batch that pops up about every 6 months and it starts all over. Forums can help a product or kill it.
A bunch of old grumpy bastards on a forum not wanting others to experiment because they are scared can run off a lot of people and slow progress in the process. Things would have been a lot different right now if the guys hadn't been so protective in 2007. If they say "this is it, the best product it can be" it leads to instant stagnation. And then there is arfcom where is seems they want to suppress the truth and facts and embrace the bad information. I guess they make money off of clicks not what the posts say. Both cartridges should be able to stand on their own without the BS being spread.

 

[Regalkismet]

Right the 27570 130s (BC .496)are the new ones designed by Litz, they are a hybrid design. The VLD Classic hunter were the ones we asked Steckler to design a few years ago.
When the older VLDs first came out they were too long but I think they must have shortened them because at 2.3 the ogive is out side the case. Either one will work in a 6.8 but I think the hybrid will be easier to tune. All of the bullets Litz is designing now are hybrids, seems like he is reworking all of the bullet weights one at a time.
LWRC designed a new receiver set and asked Mag Pul to make mags just for the 6.8. They allow loading the 6.8 to 2.32". LWRC will sell the receivers and mags as parts for builders. They are trying to organize a group buy now. By 2015 we should have larger receivers for the 6.8 and receivers for the Nexgen 308s.
C Products Grendel mags were made by ASC, it's the same manufacturer. C Products does not exist now it split into CPD and ASC. So there are really 2 companies making Grendel mags, ASC and CPD. If Bill A had made a receiver set for the Grendel 7 years ago it would be a different ball game right now. We all know now what should have been done, hindsight is 20:20.
When I started thinking about making barrels for the Grendel/264 I checked Hornadys 123 Amax ammo in my 6.5 Banshee chamber that I designed in 07. The Amax bullet was .010 off the lands. I designed the chamber for the Lapua but couldn't have been luckier with how Hornady manufactured their ammo 5 years later. Out of the box ammo will shoot under 1/2 MOA. That's pretty tough to find from production ammo and production barrels. It's a good load but I still like the 100TTSX for hunting.
Both the 6.5 and 6.8 are fine cartridges. People bickering back and forth for 8 years is because the ones doing it don't really know what the other cartridge is capable of doing. They figure it out and stop but there is a new batch that pops up about every 6 months and it starts all over. Forums can help a product or kill it.
A bunch of old grumpy bastards on a forum not wanting others to experiment because they are scared can run off a lot of people and slow progress in the process. Things would have been a lot different right now if the guys hadn't been so protective in 2007. If they say "this is it, the best product it can be" it leads to instant stagnation. And then there is arfcom where is seems they want to suppress the truth and facts and embrace the bad information. I guess they make money off of clicks not what the posts say. Both cartridges should be able to stand on their own without the BS being spread.

I wish I could have said that so eloquent and spot on as you.... I hope those that are making that money pay attention to what you just said....

 

[Jager66]

Thank you All for the great volume of information that's coming out....

Again, I am well aware there is not a "do-it-all rifle.
I know there are better calibers for long range hunting out there, but....
...my intention is to stick to the AR15 platform, so it boils down to few choices, really....

I do not care much about factory ammo's, as I do for components.
I will be reloading, so the only critical issue (if any) would be brass, even though it seems there are quite enough choices out there....

Most of the shooting would be at targets and I'd like to get a rifle which can get bullets accurately out to 500 meters, at first and, if that goes well, moving up and trying the 1K.......
I'd like to be able to take my rifle out hunting, and the terrain will be steep mountains where sometimes there might be no possibilities to "close the distance" and shot needs to be taken from great distance.....or passed on....
Biggest game would be around 100 lbs. alive, comparable to your Mountain Goat, and wind may play a big role, at times.
For those two reasons alone I think 223/5,56 has to be pulled aside, in favour of a better performer in downrange energy, for the quickest possible kill.

For the caliber you suggested......the Rifle manufacturer I would be after (European one) has the possibility to chamber both the 6,5 Grendel and the 6,8 SPC, but I have big doubts He'll do others (wildcats) like, for instance, the 6x43....

Barrel length, twist and profile can be customized (I believe barrel would be Lothar Walther), as well as a match trigger, cherakote options, rails and various components from the widely known Companies (Magpul, to say one....).

I hope this clears some mud.

Keep 'em coming !

J66

 

[bustin]

Thank you All for the great volume of information that's coming out....

Again, I am well aware there is not a "do-it-all rifle.
I know there are better calibers for long range hunting out there, but....
...my intention is to stick to the AR15 platform, so it boils down to few choices, really....

I do not care much about factory ammo's, as I do for components.
I will be reloading, so the only critical issue (if any) would be brass, even though it seems there are quite enough choices out there....

Most of the shooting would be at targets and I'd like to get a rifle which can get bullets accurately out to 500 meters, at first and, if that goes well, moving up and trying the 1K.......
I'd like to be able to take my rifle out hunting, and the terrain will be steep mountains where sometimes there might be no possibilities to "close the distance" and shot needs to be taken from great distance.....or passed on....
Biggest game would be around 100 lbs. alive, comparable to your Mountain Goat, and wind may play a big role, at times.
For those two reasons alone I think 223/5,56 has to be pulled aside, in favour of a better performer in downrange energy, for the quickest possible kill.

For the caliber you suggested......the Rifle manufacturer I would be after (European one) has the possibility to chamber both the 6,5 Grendel and the 6,8 SPC, but I have big doubts He'll do others (wildcats) like, for instance, the 6x43....

Barrel length, twist and profile can be customized (I believe barrel would be Lothar Walther), as well as a match trigger, cherakote options, rails and various components from the widely known Companies (Magpul, to say one....).

I hope this clears some mud.

Keep 'em coming !

J66

If you are target shooting to 500 and want to take deer sized game the Grendel/264 is the answer. There are more 264 match type bullets avail. If it's a custom sourcing 1 .264 barrel would be easy.

 

[Unknown]

Inside of 300 yards, there isn't enough difference between the 6.5 Grendel, and the 6.8 SPC to get excited about. The Grendel's advantage is how it performs at longer ranges because of the high BC of the bullets it can shoot.

While the Grendel is my favorite, I would strongly recommend you also consider the 6x45. You wouldn't need to buy different magazines, or bolts, just a barrel. I still think the Grendel would be superior at longer ranges, but the difference may not be worth needing to buy new magazines, brass, bolts and so on.

If you really need the long range punch for game, I think the Grendel would be the way to go. But the 6x45 is also worth consideration.

 

[Greg Langelius *]

I have Stag Model 6 Super Varminter, and I live in New York (sigh, it almost sounds like a self intro at an AR's anonymous meeting...). It has a 5.56 chamber for maximum versatility, a 1:8" twist bore, again for versatility, and heavy weight 24" stainless contour, for maximum reach and accuracy. The lower is an A2 fixed stock, and my only mod has been the addition of an extended bolt release lever that can be operated by the trigger finger.

This rifle is very accurate, turning even bulk ball ammo into the realm of acceptable accuracy. Mine is very happy with developed handloads ranging from 50gr to 75gr.

The rifle is also bulky, heavy, and the balance is unsuited to close quarters.

For that, I would like something like a 3-Gun rifle, and could consider a Stag model 3H upper to be a very suitable solution to the above issue.

Despite ammo availability issues, I think the .223/5.56 chambering to be most versatile. I also doubt the premise of an all-around, do-it-all rifle. Better to chose an application, then configure for that application. Mixing applications and/or asking a rifle configured for one application to do another is a sure path to mediocrity. If the rifle does its intended task well, let it do that task, and work up another configuration for the new task. Much the way I choose an additional upper for a better configuration to do another task, I suggest that additional uppers are the better solution to provide expanded versatility.

 

[Unknown]

Langelius makes several good points. I really doubt you will find a rifle that will "master" everything. I think the adage "Jack of all trades, master of none" would apply well to rifles too.

Perhaps listing out the uses and factors that are most important to you, and rank order the cartridge that will do that job best (3 points), satisfactorily (2 points), and poorly (1 point) next to those uses will help you out. If you have 15 things you want your rifle to do, and one cartridge consistently comes in at 3 or 2 points in many of the factors, it should point you toward the one that will best suit your needs.

I would also include factoring in things such as reloading component expense, component availability, parts and magazine availability and price, and factory made cartridge prices and selection variety, and general availability. I often find that by listing things out this way, it helps give me a much clearer view of which cartridge I should be looking at. It also helps get me away from many of my pre-conceived ideas about what would be best.

 

[LRRPF52]

I actually think we're at the stage where we can have a viable well-rounded carbine, not even a rifle, that does extremely well at close range, as well as longer distances for what the OP wants. If you look at the 6mm, 6.5mm and 6.8mm variants that are meant to fit into the AR15, it is no longer your daddy's M16.

The OP really wants a lightweight AR that will do more than just 5.56, but without having to step up to the AR10 large frame (heavy) receiver set.

The question is, where is the balancing point of performance and lightweight. If speed is the goal with high-BC's, then the 6mm Hagar, 6mm AR, 6mm Fat Rat, 240 Tomahawk, or 6x43 are really nice. Hi-power and coyote shooters are the primary market for these calibers, and they tend to use longer barrels.

If you want excellent factory ammo, plenty of brass choices including Lapua, Hornady, Nosler, and Prvi Partizan, (and is easily made from 7.62x39) with a large spread of bullet weights ranging from 85gr to 140gr, with energy that is chasing .308 closely with half the recoil, short and intermediate-to-long range capability, then the Grendel is the ticket.

If you want more parts availability, excellent factory ammunition, brass from SSA, Hornady, Federal, and Remington, and .277" pills ranging in weights from 80gr to 140gr, then the 6.8 SPC II is for you.

All of these do really well from the AR15 receiver set. The 6.5 Grendel and the 6.8 are the current mainstays because of factory ammo and widespread adoption, primarily by hunters looking for the same thing the OP is.

I know that at least in the case of my 16" Grendel, I can use it for close quarters work, then make hits on man-size targets in my region from 600-1200yds (high altitude), although I thought I was limited to 700yds with a 16" barrel. At sea level, I'm still supersonic at 1000yds with it (factory loads). If that isn't a good all-round system, I don't know what is. My 16" Grendel weighs 8.6lbs with a 2.5-10x44 PST on it, with the mag, and I haven't even tried to make it light.

 

[Regalkismet]

SMH.....

 

[steve123]

You guys have me pondering now. Just out of curiosity, how far are 6.5G factory barrels throated too?

Say if I were to point up some 140 grain Berger hybrids/ .65-.66BC and seat them out close to the lands for single feeding, what velocity out of a 20" barrel could I expect?

 

[Unknown]

Full disclosure requires me to admit being a big fan of the Grendel. However some of the 6mm offerings are very attractive because it wouldn't require additional investment in brass, bolts, or magazines, and performance is pretty good, even when compared to the Grendel.

If I were going to build from the beginning, I would look for a very light weight, fluted barrel for either the 6x45, 6x43, Grendel, or fat rat. I would use about a 20 inch barrel, with a good compensator and a light weight free float tube to keep weight down. This would give me the best compromise between velocity for barrel length, and a rifle that is quick handling enough for 3-gun, or various types of hunting or fighting.

Any selection would require figuring out how important the following factors are in selection:
1. down range energy
2. the rifle's handling characteristics
3. availability of parts, ammo, brass, and other components
4. cost of rifle, ancillary equipment, maqazines ammo etc
5. how important is it to be able to locally source spare parts, ammo, components vs ordering them from afar and waiting
6. how important is cost? If it isn't at all important, that opens up MANY possibilities.

I think the postings above all have some really good material to get the OP evaluating many factors to help make selection of the "ultimate" rifle possible.

If money wasn't a factor in any of this, ordering extra components, barrels, bolts, and factory, or custom made ammo would tremendously effect my decision. I would order everything, including spare parts while the rifle was being built. Sort of like ordering 3 of precisely the same rifle and 20,000 rounds of ammo from Les Baer at the outset. There would be a rifle, and ammo available for a long time..a couple of years anyway.

 

[Greg Langelius *]

I don't know if it meets the length requirement for the AR magazine, but my choice of the .30BR as a SR/MR chambering capable of delivering good terminal energy and stellar accuracy, while making a bigger hole in paper, as well as using a .473" bolt face diameter was driven mostly by my disappointment with Remington for altering the .30AR's base diameter o/o agreement with the standard .473" diameter bolt face. This choice is complicated by the inability/unwillingness of Rem to provide 7mm BR Rem brass. (The only easy day was yesterday, etc...; thanks Remington, once again).

Imagine an AR15 lower shooting 110 V-Max, alternating with 135gr Pro-Hunters or 135SMK's out of a .30BR upper with more chamber capacity/terminal energy than the x39. Not your Grandfather's AR-Puppy. Maybe even more interesting with heavier .30 caliber bullets being shot as subs. If you don't like the .30BR's shoulder angle, change/reinvent it to a 30B/AR (Rem?). Hey Remmy, y'all listenin' heah?

Hey; maybe you even heard it here first...

Greg