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What AR15 cartridge is a worthwhile step up from 5.56?

Why keep good info to dms? I'd love to be a fly on the wall for said conversation
I get a lot of DMs asking for things that have been published in the open for many years, basically what barrel to go with, what barrel length, accuracy vs cost considerations, to which I like to emphasize reliability and accuracy checklists that have been listed repeatedly.

I usually post photos of the barrel extension de-edging, blending, and polishing, then cover extractor considerations, gas tube alignment, barrel bedding/fitting to the upper, upper face squareness, nut and muzzle device torque windows based on barrel weights.

Dudes will often start out with one idea of what they think they want, then bounce around from economy to higher-end build, rack-grade barrel vs the upper-mid to higher tier pipes, will such and such vendor be able to deliver by hunting season, etc.

Most common use is for hunting, followed by TGT shooting steel or combo of both.

Lots of suppressor questions/considerations that play into barrel length/performance/portability.

Reloading and magazines are 2 other common sources for questions.

Grendel has been here for just over 20 years now, with 127 current SKU factory loads as of the 3 new AAC ones that just dropped.
 
Why keep good info to dms? I'd love to be a fly on the wall for said conversation
Working on a parts list now. Was going to send it to him for a sanity check. Will post it here instead and he as well as the rest of you all can tell me if I am buying incompatible parts or doing something stupid.

Will have it up sometime tomorrow I think.
 
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Looking at California police state combined with a welcome ground for the cartels, it really pushes one into a bad place of being faced with needing the proper tools for personal and family defense, vs being targeted by the police state.

Kinda damned if you do, maybe dead if you don’t.

The cartels will not be caring about mag capacity or any of CA’s infringements.

But if you can run removable 10rd mags that feed larger projectiles, there’s a benefit to that at least.
 
I hear exactly what you are saying but am hesitant to become the test case in CA as our "justice system" prefers harassing regular folks as compared to catching real bad guys.
Yeah don’t do that, it didn’t fly for the guys that tried it here in CA East 10 years ago.
 
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I hate to break it to you, but 300BO is just a 5.56 case with the shoulder lopped off. No rebated rim.
Oh, yeah, acknowledged I was wro...wr...wrong...whew, that was difficult, upthread. 🤭🤣 don't know where that piece of incorrect info came from, but it's been in my brain as fact for at least 5 years. Of course, y'all straightened me out.
 
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Oh, yeah, acknowledged I was wro...wr...wrong...whew, that was difficult, upthread. 🤭🤣 don't know where that piece of incorrect info came from, but it's been in my brain as fact for at least 5 years. Of course, y'all straightened me out.
@JS8588 earlier…


1717992752688.jpeg
 
do you expect the bad guys to be wearing body armor? or just the usual white undershirts and basketball shorts, with a bandana?
Undershirts and hoodies; at worst inside or behind a car. If anyone shows up to my parent's or my house with body armor the LAPD has made a terrible mistake and sent the SWAT team to the wrong house.
 
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Here is the promised project build list. Please feel free to suggest alternatives if something I have chosen has a better alternative or doesn’t make sense. I’m not interested in pointlessly expensive parts but am willing to pay more for increased reliability and/or performance.

This is intended as a semi-precision weapon that has more oomph than an AR15 because I am limited to 10 round mags. Significantly lighter weight than an AR10 is also a goal. Should this work well I will most likely sell my AR10 project gun and standardize on the AR15 platform. If I need more range or precision I can use my bolt guns.

The parts:

Lower – LMT Mars-L (already have)

Lower Parts Kit – LMT (already have)

Trigger – Geissele SSP (already have)

Recoil system - BCM MK2 Recoil Mitigation System, not sure on buffer weight 4.7oz maybe 5.6oz? This is one of the things I am worried about because I don’t know enough about the platform to be able to know what buffer goes with which gas port length, etc.

Grip – Magpul MOE K2

Stock – Magpul CTR with LaRue Risr and maybe an Arisaka bag rider extension



Two options for upper/handguard combo:

Option 1

Upper – BCM M4 (for the thermal fit) with a Geissele handguard (either a 10.5-inch Mk4 Federal or 13.5-inch Mk4)

Option 2 - Leaning towards this as LRRPF52 has said good things about it

La Rue Stealth 2.0 Receiver and Handguard (not sure on 10.5 vs 13 inch) but leaning towards 13 as SBR’s are illegal in CA



Barrel (18 inch) – SBR’s and suppressors are illegal in CA, and I don’t expect them to become legal any time soon, so I think a 16-18 inch barrel is going to be optimal. Bartlein or Proof Research (probably Proof for weight savings) is going to be my choice as I don’t mind paying extra when the barrel life of the gun is going to be so good. I use Southern Precision Rifles for my bolt guns but am considering Craddoc Precision for the Bartlein option; feel free to suggest other smiths to consider. Also, I want this to be a lightweight gun so what lightweight contours should I be looking at?

Gas Tube Length– I am assuming go with the longest option possible

Castle nut – Fortis K2 (already have)

Adjustable Gas Block – Riflespeed, Superlative or JP D2. Leaning towards JP.

Bolt Carrier – Hard Chromed Microbest (already have)

Bolt – JP enhanced 6.5 Grendel bolt

Charging Handle – Geissele Super Charging Handle

Muzzle Device – Supressors are illegal in CA so figured I would go with an Area 419 Hellfire linear compensator as the rifle will be low recoil and thinking that concussion and flash suppression would be the way to go. If I have to go “featureless” I can also use a regular muzzle brake.

Magazines - I am aware that Geissele, ASC, PRI, Amend2, CProducts, and Elander make magazines. I was going to start with Geissele and Elander 10 rounders first (Elander because that is what LRRPF52 uses and a Geissele because they make nice stuff, and I am curious if spending more money can make magazine issues go away).

Primary Optic - Something FFP with a nice tree reticle in the 2-10 or 3-15 range; maybe a March 1.5-15 dual focal as I am very curious about that optic. I do have a March 4.5-28 for the AR10 project so that is could an option as well.

Optic Mount - Nightforce ultralight. Folks feel free to suggest others.

Secondary Optic – 45 degree offset red dot, closed emitter. Trijicon, Holosun, or Aimpoint.
 
I'm invested in the 5.56 in the AR platform, for for all practical needs, at reasonable sane ranges, MK-262 is sufficient.
But if I wanted to step up performance, in spite of some of the issues, I'd go with the 224 Valk slinging 88's as that is a substantial step up from the 77's at 2750'ish..

For any needs beyond that, perceived or real, I'm outta the AR platform & into a bolt gun.

YMMV

MM
 
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I get a lot of DMs asking for things that have been published in the open for many years, basically what barrel to go with, what barrel length, accuracy vs cost considerations, to which I like to emphasize reliability and accuracy checklists that have been listed repeatedly.

I usually post photos of the barrel extension de-edging, blending, and polishing, then cover extractor considerations, gas tube alignment, barrel bedding/fitting to the upper, upper face squareness, nut and muzzle device torque windows based on barrel weights.

Dudes will often start out with one idea of what they think they want, then bounce around from economy to higher-end build, rack-grade barrel vs the upper-mid to higher tier pipes, will such and such vendor be able to deliver by hunting season, etc.

Most common use is for hunting, followed by TGT shooting steel or combo of both.

Lots of suppressor questions/considerations that play into barrel length/performance/portability.

Reloading and magazines are 2 other common sources for questions.

Grendel has been here for just over 20 years now, with 127 current SKU factory loads as of the 3 new AAC ones that just dropped.
You know, for purely selfish reasons (reducing time repeating yourself) and altruistic ones (spreading Grendel Gospel, helping fellow man), you could collect this info into an article here on the Hide. Or a website that you create. Or in a PDF that you post a number of places.

Might reduce/contain/simplify replies to the stream of questions you get, while simultaneously making learning about Grendel AR15’s easier and more time/resource efficient.
 
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You know, for purely selfish reasons (reducing time repeating yourself) and altruistic ones (spreading Grendel Gospel, helping fellow man), you could collect this info into an article here on the Hide. Or a website that you create. Or in a PDF that you post a number of places.

Might reduce/contain/simplify replies to the stream of questions you get, while simultaneously making learning about Grendel AR15’s easier and more time/resource efficient.
I agree would be great to have a pinned thread
 
You know, for purely selfish reasons (reducing time repeating yourself) and altruistic ones (spreading Grendel Gospel, helping fellow man), you could collect this info into an article here on the Hide. Or a website that you create. Or in a PDF that you post a number of places.

Might reduce/contain/simplify replies to the stream of questions you get, while simultaneously making learning about Grendel AR15’s easier and more time/resource efficient.
There's a mega thread on Arfcom and entire forum dedicated to the cartridge.
 
I'm going to give the weird response here.

Where you live, if you *really* want something that deals with 2 legged predators better than 556...

The answer, in a small frame, is 7.62x39.

No, you're not going to get better range out of it. You're building an AR10 for that anyway.

The ammo is still affordable, relatively speaking and it will put more of a hurt on something inside of 200 (or, if you're Rob Ski, which you aren't and neither am I, inside 500) yards.

300 BO will do it too, but I have an irrational hatred of rebated rims.
not a weird answer at all, now that hornady is making a reliable cycling subsonic expander for it too

the downside of an AR in 7.62x39 is the magazines (I say from personal experience), if possible get one of the variations that uses AK mags. either PSA KS-47 or a CMMG Dissent. KS if you want maximum parts compatibility besides reciever/BCG/barrel, dissent if you want a folding stock and maximum reliability.
 
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I have no idea why someone would go to 7.62x39 or 300blk to shoot supers when there is this cartridge called the 6.5 grendel. I could see if blaster ammo was 15 cents per round again.
barrier blindness with the right kind of ammo, and ability to swap to subs with just a mag change.

also with how many bangers are using dracos and similar crap, when they fuck around and find out, you get more ammo
 
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barrier blindness with the right kind of ammo, and ability to swap to subs with just a mag change.

also with how many bangers are using dracos and similar crap, when they fuck around and find out, you get more ammo

You trying to tell me 7.62x39 and 300blk pentrate better than the 6.5 grendel?

Also why I mentioned shooting supers but you can shoot subs in a grendel too.

But It's not like you just take a rifle that runs on supers and stuff in a mag of subs and it runs.
 
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I've been through the 6.8 SPC, 6.5 Grendel and 6mm ARC, and for the specific ask in the OP, the ARC is my preference, and honestly my favorite AR cartridge. In terms of trajectory, wind resistance, etc the ARC is the best. For my personal usage where hunting is more of a focus, I like that I can get pretty much any available 6mm bullet up to a normal operating velocity with the ARC. I still have my Grendel and it's a good cartridge, but the subset of 6.5 bullets that are really optimal for the Grendel is kind of limited.

For the OPs real uses per later messages, I'd probably just stick with 5.56 with good loads, unless you just want something different, then see above.

I honestly find the hype machine for the 6 Max perplexing, especially on this site where heavy, efficient bullets are usually a focus area. Unless your main criteria is " bigger bullet without having to get a new bolt" I just don't get it, velocities with lighter bullets are similar or slower than the ARC, and velocities with the heavies stuffed deep down in the powder space are certainly slower. After a couple decades of smarter cartridge design focused on optimizing case length and chamber designs for modern bullets, the 6 Max is a strange throwback.
 
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You trying to tell me 7.62x39 and 300blk pentrate better than the 6.5 grendel?

Also why I mentioned shooting supers but you can shoot subs in a grendel too.

But It's not like you just take a rifle that runs on supers and stuff in a mag of subs and it runs.
1) barrier blindness does not refer to raw penetration, but also to projectile behavior after passing through a barrier. longer, slimmer projectiles like 6.5 exhibit significantly more tumbling and loss of accuracy and momentum when penetrating barriers (this is also why light 5.56 FMJ can cause so much damage to flesh)

2) Yes, when certain calibers are properly set up, they will indeed cycle subs and supers on the same gas setting without issue, 7.62x39 and 300blk in the correct barrel lengths are the primary calibers capable of doing such.
 
1) barrier blindness does not refer to raw penetration, but also to projectile behavior after passing through a barrier. longer, slimmer projectiles like 6.5 exhibit significantly more tumbling and loss of accuracy and momentum when penetrating barriers (this is also why light 5.56 FMJ can cause so much damage to flesh)

2) Yes, when certain calibers are properly set up, they will indeed cycle subs and supers on the same gas setting without issue, 7.62x39 and 300blk in the correct barrel lengths are the primary calibers capable of doing such.
Can you cite some source material for number 1? I see bonded ammo for 223 and they were supposedly making bonded 6mm bullets for some units using 6mm arc also. Which 30 cal bullets are too long? Is the 175g used too long to perform well through barriers? Are the 750g 50 cal bullets too long to perform well though barriers?

Number 2, sure you can get it work. I have never seen one that's what I would call a reliable rifle though.
 
I'll get you some reading material on number 1 when I'm back at home. it's a very well-known topic though and discussed at length all over the place, especially by Law Enforcement as they have the most at stake with it. you can make grendel bullets that are barrier blind, but the terminal performance will be lacking because you will need a solid core penetrator after you reach a certain ogive length vs diameter. 30cal tends to reach that point around the realm of the 215gr VLDs and other similar long ogives meant for use in 300 Norma Mag, etc

The 175gr and 168gr AMAX are what's commonly used by law enforcement because of the metal tip providing better ballistic barrier blindness through laminated glass.
Number 2, sure you can get it work. I have never seen one that's what I would call a reliable rifle though.
Standard AK with Hornady 225gr SubX works just fine, or a Sig MCX Virtus 9" bbl in 300blk. the latter is in combat arms use with US SF and Dutch Marines among other military and law enforcement actors, to the point that wilcox makes a sighting system designed very explicitly for a switchable zero: https://wilcoxind.com/products/combat-systems/laser-aiming-devices/product_combat_boss-xe
 
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If that's as far as you're going, I say stick with 5.56. Spend that extra gun on ammo or food, or the training you mentioned earlier in the thread. Or, by the time you outfit the new rifle with an optic, mags, ammo, money spent to practice with the new setup, you could be into a fairly decent thermal. Night time capabilities in that situation will be priceless.

I've got a couple of older thermals. A flir pts233 and al old 75mm armasight Zeus. I've got about 4k wrapped up in the two of them. I'd get rid of the 233 but I won't get anything for it, so it'll probably end up on a 22 for night time chicken coop defense. The Zeus can do 2-300 yards in the dark in decent conditions.

You can get into a pretty good thermal now (a lot better than what I have) for around $3,500. Heck, there's a used halo lr in the px for $4,200 right now.
Early this year I went to an intermediate rifle class and it was taught by a former Army sniper named Kevin Owens. We started out with the classroom part and towards the end of the conversation he said that he almost always get asked about a shit hits the fan scenario.

I am going to miss some of the specific things but his kit that he keeps with him in his Sprinter Van

Bolt action 308 with a suppressor and 3-12 S&B scope. He had mags marked with rounds that were handloaded to be subsonic.
9mm pistol with a suppressor and 147 grain ammo
A minimalist plate carrier with lvl 3 plates front and back, he was only concerned about stopping what is most common.
A ballistic helmet (I think high cut Opscore) but he had a PVS 14 on one side and some kind of thermal on the other. The thermal can be taken off the bridge and clipped on in front of his day optic. He then spent 10 minutes explaining thermal > name it.
 
.22LR

Same size projectile as 5.56, but 8% lighter and 4.33% shorter, and costs slightly less. The “LR” stands for “Long Range.”

The only downside is how it punishes steel.

This is also why you will never see any .22LR rated body armor. It would weigh about 53-pounds per plate, and while you may be able to technically stop the projectile itself from penetrating, the energy transfer would liquify your internal organs.
 
.22LR

Same size projectile as 5.56, but 8% lighter and 4.33% shorter, and costs slightly less. The “LR” stands for “Long Range.”

The only downside is how it punishes steel.

This is also why you will never see any .22LR rated body armor. It would weigh about 53-pounds per plate, and while you may be able to technically stop the projectile itself from penetrating, the energy transfer would liquify your internal organs.
Dammit, nobody tells me these things. Now I need to go out and find a Dillon minigun chambered in 22LR so I can be ready for the end times...
 
I am always amused by people looking for a hardware solution to a software problem.

Buy ammo and train.

Surprise surprise Sgt. couldn't agree more . Was over at our local range Tuesday and helped a distraught somewhat confused gentleman operate his brand new 320 Legion Sig. He claimed he was a revolver guy and not familiar with semi auto ( he didn't have too it showed ) .
So I helped him orientate his bearings around it . Also advised him of a couple of optics which would improve his survival ,should that become necessary . Also some ammo suggestions ,as I explained not all were equal and choosing correctly could make one Annie Oakley or the range clown . Buy cheap reloads and PRACTICE as much as you can afford too ,then use GOOD factory carry stuff after sighting in the pistol with Factory ammo .
As I demonstrated with MY Canik , selecting proper ammo does make a difference . ;)
July 2 ND. I get his Sig and a check ,so as to install a RMR sight a Romeo X Compact Rose ,should do the trick . I've got to stop advising , as it eats MY time but hard to say NO too Shooters . :rolleyes:
 
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I used to do that. Now I mind my business.

I go to the range to focus on what I want to get done. Everyone else who isn't with me doesn't exist.

In fact when I see someone who is clueless with a gun I get away from him ASAP.

Since becoming a NRA certified Master Instructor 2019 ( certified to teach all discipline's including reloading ) , I can't do that any longer . Yet having my own Pistol 0-60 yd. and 165-1177 yd. Rifle range does allow uninterrupted range time . So I help when I can ,as others took time too help Me .
 
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What other cartridges that fit in an AR15 provide enough of an increase in performance (increased range, dealing with wind drift better, terminal performance, etc.) over 5.56 that make them a worthy upgrade from 5.56? I know there are the duds like the .224 Valk and .22 Nosler and there are also newcomers like the 6 and 22 ARC as well as the 6.5 Grendel that has been quietly chugging along; but do any of them bring enough of an increase in performance to the table to be worth owning? Or is it just the case that if you want a meaningful performance upgrade step up to an AR10 in .308/6.5?

Thanks for reading and looking forward to your responses.

P.S. this question may have been triggered by reading about what you all are doing with your 6ARC and 6.5G rifles and having a spare lower just lying around...
200-300yds, in the AR15 platforms, I don't think anything is better when all things are considered

x39 is a close second
 
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Since becoming a NRA certified Master Instructor 2019 ( certified to teach all discipline's including reloading ) , I can't do that any longer .

You do what you want but understand that you're under no obligation to help people learn how to shoot unless they pay you.

Being an NRA instructor isn't like being a doctor (with legal responsibility to provide aid).
 
I I wasn't limited to 10 round mags I'd be on board with this 100%. I'm looking at bigger stuff as my thinking is if I'm limited to 10 they might as well be stronger medicine.
Tbh getting good with SKS stripper clips might well be worth your time over a bastardized AR. If it’s a Chinese one you even get the pointy end!
:ROFLMAO:

I’m serious though, a good sks fed actual good ammunition (Prvi Partisan brass case, or Hornady) will shoot quite well and be very reliable, with the upside of having the clip guide to easily reload compared to California gimped ARs.

Another option would be an M1 Garand, for the same reason. Easy to get ammo for, easy to reload in a hurry

Both guns have good non-destructive options for adding modern optics ahead of the action

I’ve not brushed up on commiefornia laws, but if you can have higher capacity with a fixed mag, then stuff the SKS in one of the replacement poly stocks with a fixed 30rd mag (you’ll need to pin the mag in place) and just feed it from the clip guide
 
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I used to do that. Now I mind my business.

I go to the range to focus on what I want to get done. Everyone else who isn't with me doesn't exist.

In fact when I see someone who is clueless with a gun I get away from him ASAP.
Mind your business, but keep 1 eye on theirs.

Fuck, the range I’m a member at generally doesn’t have an RSO on duty- not enough traffic. But, was there with a non-member guest and an NRA certified RSO showed up to shoot. Biggest douche on the line. (No, that’s a lie. The f class guy that continues his 1 shot every 3 minute pace for 15 minutes while others are waiting to hang/retrieve targets was the biggest douche.) I’ve got 2 rifles with obviously open actions pointed down range on an otherwise unused bench and he’s acting like I killed someone’s because one of them doesn’t have a chamber flag. Is this the wrong place to say “fuck the fucking NRA?”
 
Mind your business, but keep 1 eye on theirs.

Fuck, the range I’m a member at generally doesn’t have an RSO on duty- not enough traffic. But, was there with a non-member guest and an NRA certified RSO showed up to shoot. Biggest douche on the line. (No, that’s a lie. The f class guy that continues his 1 shot every 3 minute pace for 15 minutes while others are waiting to hang/retrieve targets was the biggest douche.) I’ve got 2 rifles with obviously open actions pointed down range on an otherwise unused bench and he’s acting like I killed someone’s because one of them doesn’t have a chamber flag. Is this the wrong place to say “fuck the fucking NRA?”

NRA instructors, Appleseed instructors, USCCA instructors, anyone who imitates Rob Pincus......

Nobody I'd use to learn anything.

LOL