Barrel twist for 55 grain Hornady fmjbt's ?

[1911jerry]

I just got through with the search function and am now more cornfused...

I have a 1 in 8 twist DPMS barrel in my AR, about 18 inches.

Would the 55 grain bullet shoot accurately in this combo?

Thanks guys
It's hell being a newbie....

 

[sixfiveguy]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

You will be fine with the 1-8" twist. If you wanna run a heavier pill you could stabilize up to a 75gr bullet with the 8 twist.

 

[DedicatedShooter]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

My buddy shoots 55gr-75gr all day in his RRA 24" bull barreled AR with a 1:8" twist.

We shot the 55 VMAXs at a 12"x17" steel plate set out at 800 yards, and the 55's beat out the 75 AMAXs, believe it or not.

bottom line, you're good to go with a 55gr in a 1:8" TW

 

[Grump]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

No, they won't shoot accurately at all, if your definition of accuracy starts at .75 MOA and goes smaller from there.

Not the barrel, it's the bullet.

A 1:7 Colt HBAR I've played with shoots those Hornady bullets 2 to 2.5 MOA pretty reliably. No, with complete reliability. Match bullets from 52 gr up to 80 gr long-loaded, 1 MOA if I'm lucky, 1.5 MOA max and averaging 1.25 or so IIRC. That one's the barrel being a partial limitation.

I do not know whether the multiple reports of 1 MOA with Hornady 55-gr FMJBTs are true averages, or "best of" groups that happen only once per shooting session.

 

[shooter19802003]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Six Five Guy</div><div class="ubbcode-body">You will be fine with the 1-8" twist. If you wanna run a heavier pill you could stabilize up to a 75gr bullet with the 8 twist.
</div></div>

Pretty much what he said. 1-8 is good for 55gr to about 75gr. Truthfully...I wouldn't expect anything too great out of anything above 69gr with that.

 

[longshot1911]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

Wow,

I would take the comments above with a grain of salt. The accuracy comments have little to do with the twist rate of the barrel or bullet selection, and very likely everything to do with quality/condition of equipment and shooter skill.

I used a DPMS 20" 1-8 twist on my CMP Service rifle for several years. It reliably shot 1" or better groups with iron sights using the 77gr SMK at mag length. The load worked well enough that I used it across the course.

My bulk plinking ammo is loaded using surplus WC 844 powder, whatever CCI primers, LC brass, and either pull down 55g FMJBT projectiles (purchased from Hi-Tech), or the Hornady FMJBT (purchased from Midway) . I load this all on a bullet feeder equipped Dillon 1000 with no special attention. At 100 yards, this ammo matches the 77g SMK's (roughly 1" with iron sights), and is used on reduced targets for offhand practice.

I recently built an 18" (1-8 twist) fluted bull barrel AR for kicks. When mounted with my S&B 5x25, it placed the first 10 rounds in a .75 in group. Again, no special attention paid to the ammo, 55g FMJBT.

After convincing myself that it was time for a new service rifle barrel, I purchased a 1-6.5 twist Krieger so I could play around with the 90g SMK's. Again, this barrel will shoot 1" or better with the 55g FMJBT at 100, which is used for practice.

Is this the most accurate bullet design available? No. Can a good rifle with a moderate shooter fire this bullet well? Yes. I would not expect as much at longer distance due to wind considerations, but for short range plinking and practice (100yards), they are an affordable alternative. Also, the 55 grain bullet will work in just about any twist barrel available.

 

[1Sg (ret)]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

You are on the right with track with the Hornady 55 fmj they are almost as accurate as 55 vmax out of my 1/7 6920.

 

[Rob01]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

The twist is fine with that weight bullet. My 8 twist 18" POF shoots the 52 VMAX very accurately. That said there is more to the equation as to whether it will shoot accurately in your rifle. There's the rifle itself and the load used which will add into it. So knowing the twist will work now get some and try them out and see if you can work up a good load.

As mentioned though if you wanted a longer range bullet try out the 75grn AMAX or BTHP or the 68grn BTHP. All shoot great out of my POF.

 

[Jerry m]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

Note that the faster twist will amplify any imbalance in the bullet. Shooting FMJ mil spec will not shoot as well as 52-55 grain MATCH grade bullets.

Good luck

Jerry

 

[pacomdiver]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

longshot,
give the 90g JLK vld's a try, we use them in a 6.5 twist white oak service rifle barrel thats throated for them and it shoots sweet, but its a single load round, for the fast fire stages, we use 68 or 69g hornadys and sierras interchangably

 

[BCP]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

If you want to shoot a lighter bullet that is accurate use a 52 BTHP (nosler bulk packs are only 20$ more than the hornady FMJ's).

My 18" 1:7 shoots 52 grainers as accurately as anything else I've put through it, at least to 300 yards.

 

[BCP]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Grump</div><div class="ubbcode-body">
I do not know whether the multiple reports of 1 MOA with Hornady 55-gr FMJBTs are true averages, or "best of" groups that happen only once per shooting session. </div></div>

I've never been able to get hornady fmj anything shoot sub MOA. Usually about 1.5 which is in line with PMC223, Remington223, 308PMC, etc etc.

 

[longshot1911]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pacomdiver</div><div class="ubbcode-body">longshot,
give the 90g JLK vld's a try, we use them in a 6.5 twist white oak service rifle barrel thats throated for them and it shoots sweet, but its a single load round, for the fast fire stages, we use 68 or 69g hornadys and sierras interchangably</div></div>

Thanks for the tip. Yes, all of the 90's will be single load. I will very likely give the JLK's a try, but I get a very good deal on the Bergers, so I will be hard to budge. I am looking forward to the spring shooting season, as I would like to try both at 1000. I will likely throw my match rifle barrel on a flat top reciever with good glass, as I would hate to have poor eyes taint my impression. Hell, if I have the elevation, I may just shoot irons just for shits and giggles.

As for short line, I have used 77 SMK's thus far, but will likley shoot the 75 gr Hornady's next spring due to cost.

BCP

FMJ's can be very accurate. Check out some of the Lapua D46 .30 caliber rebated boat tail bullets some time. While surpassed by many of today's bullets, these will still supprise you.

 

[1911jerry]

Re: Barrel twist for 55 grain Hornady fmjbt's ?

Thanks guys,

I bought 12K of these Hornady 55 grain fmjbt's a few years ago at a great price. I plan on using them in local 3 gun matches and plinking out to 200 yards, so I think I will work up a decent load and move on.

I plan on reloading for my 308 next year, so my efforts and dollars will be focused on good equipment and components.

Thanks

JS