Any luck with heavies in a 1:9 twist .223?

[29aholic]

If so, what's your load.
I am running a Stag/S&W hybrid M-4 with a 1:9 twist. I get good results with 60ish grain bullets, but was thinking I might want to try something in the heavier/better BC class so I am reaching out to the experts.

 

[groundhogbuster]

I've had 9tw that did pretty decent with 69's but my best luck is with 1/8 from 50-77gr, and they all shoot like a laser. A WYLDE chamber is gonna shoot a bit better than a NATO in my experience. For the 80's and even 90's, I'd go no higher than a 7tw, and a 6.5tw if possible. I have a Noveske with a 6.5tw Hart that does really good to 1k with 90gr Bergers, but it's only single feed, and your defeating the purpose with an AR. I just did it because I won a free .223 AR barrel at a Match.

 

[supercorndogs]

i shoot 77 sierras out of my 1in9 but it is a 26" remington

 

[Steel head]

I have a 16" carbine 1-9 that shoots 77's quite well and they're stable at least to 400yds.
I don't think that's the norm at all.
You won't know till you try em.

 

[gstaylorg]

Diego Ted on the forum here recently posted some info on his load development for a 9-twist Savage .223 bolt gun. He has had very good luck with the 75 gr Amax (see following posts). A 9-twist is cutting it fairly close for this bullet, but it seems to work well for Ted. This bullet has a BC that is slightly higher than a 77 Sierra, but a little less than the various 80 gr .223 bullets that are out there. If it shoots well out of your 9-twist barrel, that is about the best you're going to find that is going to work well out of a slower twist rate barrel.


http://www.snipershide.com/shooting...load-60-shots-way-should-lol.html#post3275718

http://www.snipershide.com/shooting...liking-rifle-help-me-read-wind-300-yards.html

 

[29aholic]

Thanks for the replies so far, I hope to hear more

 

[BoilerUP]

I've never had any issues running the 75gr Hornady HPBT from a 1:9 barrel, be it a 26" Savage, 20" Savage, 20" AR, or 16" AR. In fact, that 26" Savage was a no-joke half MOA factory barrel with the 75gr HPBT and 24.0gr Varget.

Also:

1:9 twist barrel
77gr SMK @ 0.994" OAL
2500fps (*easily* achieved even in a 16" carbine)
Sea Level
Standard atmosphere (59F, 29.92Hg, 0% RH)

The stability factor is 1.34.

 

[Captramrod01]

Pretty much every 1-9 should be able to handle at least 69 and 77gr bullets. Some will be able to do the 75gr amax/bthp but keep in mind these are longer then the 77gr class of bullet so it will vary rifle to rifle. My old savage 223 with a 1-9 shot the 75 amax very well.

 

[ksthomas]

29aholic,

No, the 1x9" won't handle a 77 or above, but there's a bit of a rub to it from there. You'll hear from many who have used them in their rifles and have gotten good results from the 77s, and that's quite possible. Most of these, I'm willing to bet, don't have an actual 1x9" twist. In the case of buttoned barrels, it's not at all uncommon for the actual twist to vary by +/- a half inch or more, in either direction. In otherwords, that 1x9" twist could very well be a 1x8.5" or faster, which would handle the 77s just fine in many cases. Since so many barrels are buttoned today, it's a very common situation. In a cut barrel, if it's advertised as a 1x9", you can pretty well count on it being exactly that, simply because of the difference in production methods. In any case, it's often worth trying with a combination that may be marginal on paper, just to see what happens in the real world. Don't be surprised if it doesn't work, but if it does, you're golden. Several other factors play into this as well, so there's a number of things that get into the equation, for what that's worth.

 

[29aholic]

29aholic,

No, the 1x9" won't handle a 77 or above, but there's a bit of a rub to it from there. You'll hear from many who have used them in their rifles and have gotten good results from the 77s, and that's quite possible. Most of these, I'm willing to bet, don't have an actual 1x9" twist. In the case of buttoned barrels, it's not at all uncommon for the actual twist to vary by +/- a half inch or more, in either direction. In otherwords, that 1x9" twist could very well be a 1x8.5" or faster, which would handle the 77s just fine in many cases. Since so many barrels are buttoned today, it's a very common situation. In a cut barrel, if it's advertised as a 1x9", you can pretty well count on it being exactly that, simply because of the difference in production methods. In any case, it's often worth trying with a combination that may be marginal on paper, just to see what happens in the real world. Don't be surprised if it doesn't work, but if it does, you're golden. Several other factors play into this as well, so there's a number of things that get into the equation, for what that's worth.

Thanks Kevin (and everyone else) that is good info. I see you're not that far from me, I am pretty close to Collins, MO

 

[bottom_gun]

In fact, that 26" Savage was a no-joke half MOA factory barrel with the 75gr HPBT and 24.0gr Varget.

My 26" 1:9 savage did the same with 75gr AMAX over 24.5gr Varget just touching the lands. In the McRees chassis it would consistently put 5 shots in a dime.

 

[ksthomas]

29aholic,

In Sedalia this morning, but heading over to St. Louis BR Club for an ARA/PSL match this weekend. Yeah, we get around. Stop on by if you're ever in the area!

 

[Greg Langelius *]

My 20" Mossberg MVP Predator and my CMMG 16 Bull WASP Upper have 1:9" nominal (i.e. published) twists, and both handle HDY 75gr HPBTM very nicely at distances out to 250yd. The load is PPU match brass, the HDY 75 HPBTM at 2.260" OAL, CCI BR-4, and 23.7gr of Varget.

They are also very accurate out of my Savage 11VT .223 (twist unknown), and my Stag 24" 1:8" nominal twist Model 6 Super Varminter with the same load.

The Uppers cycle effectively, and the brass emerges in good shape.

Hornady's loading manual lists this as a max loads for bolt guns. My Stag lower serves both Uppers, and has been modified to conform to NY Assault Weapon Ban-Compatible stock requirements, which also necessitated changing out the buffer and tube to carbine specs.

Greg

 

[rduckwor]

A couple of runs in my MVP Predator. I didn't spend too much time on the heavies hoping to get more velocity out of lighter bullets.

Still trying to decide whether or not to like this rifle.

 

[dauntedfuture]

My 1/9 Winchester varmint rifle shoots 80's well at 600, but its the exception and it has a 24" barrel, and it could be a 1-8.5 or better. With a 16" 1/9 I suspect that you will top out with a 69g bullet at Magazine length or a 70 VLD seated out long.

 

[Greg Langelius *]

Looking at the chronography, I really don't get much meaning; I suspect 3 rounds is not enough to have meaningful value, if I'm reading this data correctly. Matters like ogive and neck tension variances have too much weight in such small samples. Rather than 3 rounds, I'd be checking 10. Load development selections have far reaching consequences. I like to have repeatable results with large samplings upon which to base my bulk ammo production.

One of the things I did with my MVP Predator was to mount up the same scope on it, a Bushnell AR .223 Optic BDC 3-12x40 scope, as I have on my 16" AR upper. It makes it a bit more easy to like. The things I like most about the MVP Predator are things I might not like so much in my heavier, more precise rifles. I see it more as a field rifle than a range rifle, where compact mobility and decidedly lighter weight should count for more.

With the right ammo, it performs quite respectably. I have a generic accuracy load for my .223's that brings out most of their potential across the board. It's PPU (Prvi-Partizan) match brass, CCI BR-4, 23.7gr Varget, and the HDY 75gr HPBT Match at 2.260" OAL. Shoots well under 1" at 100yd in my MVP Predator.

My next loading development project is a .223 round that employs the Win 64gr Power Point.

Having tried M855 62gr, and TulAmmo 55gr with dismal (3"-4" at 100yd) results, I was kinda disappointed with my MVP, but feeding it a better handload changed all that. My Son-in-Law was flatly astonished at the difference handloads make when we got him sighted in for hunting season this past Sunday.

Greg

 

[rduckwor]

These were OCW runs to see if anything jumped out at me.

I really haven't had much time to fool with the MVP. I do agree that its a field rifle rather than a range toy. I would almost be tempted to turn it into a scout rifle format if I had time to hunt.

As such it fills a niche very well.

 

[hermosabeach]

I am running a Stag/S&W hybrid M-4 with a 1:9 twist.

What length is your M4 Barrel?

 

[29aholic]

What length is your M4 Barrel?

16" (I think) standard Stag length carbine barrel

 

[groundhogbuster]

Also remember some folks are saying they shoot fine in their 1/9tw bolt guns. In a bolt gun you can run the pressures up higher to give that pill a lil more kick than a gasser, and also you have to remember that it's 16" as well. Much different than a 20" esp a 26". Also "ksthomas" is exactly right. All my AR's without "cut" barrels run different. I have a Custom Noveske in .556 that is marked an 8tw, but running a rod n patch it's clearly a 7.7tw, and one of the earlier DPMS .556 rifles was a labeled 9tw and I couldn't shoot 77's and everyone was saying theirs would. Well after checking it was around a 9.5-9.7tw. My RRA's with 416ss 8tw are very close to 8, and 1 0r 2 are 7.5-7.7tw. The only way you'll ever know is load em up n shoot. Everyone told me the Remmy 700 sps with 1/9.125 tw in .243 wouldn't shoot the 105 Amax, or Berger 107's. Well it shoot's 107's into 1/2 moa or better everytime I've shot it, and at 700yds it put the 105's into a 3.7" group for 5 shots. Yea I run H1000, and Mag primers, but it does what I want, and it will soon have a Krieger 7.5tw hanging on it. I don't think many people (at least on this forum) Lies for the heck of it, but 1 thing's for sure "The bullet NEVER Lies" Load em up n shoot! and post some pics.

 

[Khromo]

I have a 24", 1-9" AR that shoots 77grain SMK's and 75 grain Hornady HPBT's very accurately out to 300 yards as long as I keep the velocity up. At lower velocities, those longer bullets aren't spinning fast enough to stabilize.

I had all but given up on heavier bullets in that barrel until a guy explained how the velocity affected the speed at which the bullet spins. I always lean toward lighter loads, so I never would have figured that out for myself. When I told the guy I was loading towards the starting loads, he began hollering "Those bullets want to be driven FAST!!!"

He was right! Problem solved!

 

[bruddah]

I've never had any issues running the 75gr Hornady HPBT from a 1:9 barrel, be it a 20" AR, or 16" AR.
:

My experience as well. Never tried a 77 gr in that twist though.

 

[OF&B]

Stability is more length issue than weight, and 77s are generally shorter than 75s.

223 77s are generally a special class of bullets optimized for AR15 magazine lengths. Their ogives are limited to 0.500" (2.26" OAL - 1.76" case length = 0.500" ogive). 75s as a group are designed with BC in mind.

A Berger 75 grain boat tail is 1.063" long, their 77 is 1.029". Their stability factors with a 1:9 twist under nominal conditions are 1.11 and 1.25. A 77 smk is only 0.994" long and it's stability factor under the same conditions is 1.39. A little length matters a lot. The yellow light for stability goes on at 1.4, it gets really iffy below 1.2, and the red light comes on at 1.0. The ballistic coefficient starts to deteriorate significantly below 1.5. The stability factor varies as the cube root of velocity, so within the same cartridge it's not going to help much unless its a big change and you're really close. Going from 2600 fps to 3000 changes the stability factor 5%, or about 0.07 for the range around 1.4.

A 77 will likely work with a true 1:9 or faster barrel, with a 75 not so much.

 

[BoilerUP]

The 75 HPBT is a much different animal than a 75 VLD like a Berger or Amax.

 

[spamassassin]

I run 70gn bergers and 75gn hornady BTHP's in a 9 twist 24" barrel at ~2950. They've been fantastic out to the transonic as long as I run them at top charge weights.

 

[29aholic]

Thanks for all the replies. I am not sure I really want to load for this gun as I bought it with SHTF purposes in mind and stocked up on ball ammo accordingly.
However, it does appear to shoot really a lot better than I expected, I can borrow a set of dies so I might play with it a little when I get the rest of my guns lined out.