My next AR disease---- what barrel twist

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[ARCHIVED THREAD] - My next AR disease---- what barrel twist

Posted: 11/25/2014 12:43:56 PM EDT

I have 3 AR15 uppers in 5.56. All are 1/9 twist rate. They were all bought without a ton of thought into what bullet weight I would shoot. I wanted something to go bang and use standard bulk ammo which is generally 55gr/62gr. For that, I trusted the places I bought my uppers from and I've been very happy with the products I've received(Del-Ton and Hardened Arms uppers).

Now that I am getting into reloading, I'm wondering if I'm missing out on the higher grain bullets. Sounds like a "good excuse" to buy another upper with 1/7 or 1/8 twist to get into the higher 60's to lower 70's gr range. I'll have to look into the max weight that will still allow me to get my COL into a usable range in our mags though, which I think is in the 75-78 gr range before the length gets too long, but I could be wrong.

Another side of me says to keep everything standard as I would have to keep ammo separate, and if the SHTF and I had to press into service the wife or kids to help load, shoot etc... the added types of ammo could become a cluster$%ck. Just voicing my thoughts here if that makes sense.

I must confess I have very little knowledge of how the ballistics change in the higher gr weights, but my idiot way of thinking, I would imagine since all of my barrels are 16" or shorter(pistol builds possible in future) the 55gr projectile was ideal in a 20" barrel, a higher gr weight may get back some of the power the little guy is giving up with velocity from the shorter barrel.

I have no plans of suppressors on a 5.56, throwing that out there in case it influences advice. Possibly on a future 300blackout build though, but that's another topic, or maybe not. Maybe the 300 blackout is a better idea vs heavier 5.56 bullets??????

my guns are used to put holes in paper, and for potential self defense.

PS just looking for opinions and information, not the holy grail of diatribes on what is better for YOU and everyone else is dumb. I thank everyone for helping me :)

Posted: 11/25/2014 12:49:05 PM EDT

[#1]

Twist rate correlates to bullet length, not weight.

I only use 1/7. Lets met shoot just about everything.

Are suppressors even legal in IL?

Paper punching: I'd just stick to 5.56. You'll just spend more for .300 BLK for nothing as you probably don't hunt and you "have no plans" for a suppressor.

I honestly wouldn't even consider a .300 BLK unless I had it suppressed.

Posted: 11/25/2014 1:00:12 PM EDT

[#2]

thx for the reply

Ok, re: twist, I must be mis informed that twist was to compensate for bullet weight, thx for letting me know.

Re: suppressors in IL; AFAIK, where I am, it would be ok, but I would have to do the rest of the tax stamp stuff like get the sherrif to sign off etc... Pay my fees. Around Chicago, I'm sure you wouldn't be able to though. Can't own more than 10 round mags in Chicagoland, unless you are a thug/criminal.

Posted: 11/25/2014 1:23:34 PM EDT

[#3]

Depending on the load you plan to shoot would determine the twist. 1/7 1/8 or 1/9 all are great twist. 1/9 does better with shorter lighter bullets 1/7 does better with longer heavier bullets 1/8 does fine with both. Some people report better accuracy with 1/9 with lighter 55gr ammo that is usually most commonly shot by most shooters.

I have 1/8 and 1/7 rifles myself but twist has never been an issue when choosing a rifle.

Posted: 11/25/2014 1:51:37 PM EDT

[#4]

1in24...Lol

Posted: 11/25/2014 2:06:08 PM EDT

[#5]

Quote History

Quoted:
thx for the reply

Ok, re: twist, I must be mis informed that twist was to compensate for bullet weight, thx for letting me know.

Re: suppressors in IL; AFAIK, where I am, it would be ok, but I would have to do the rest of the tax stamp stuff like get the sherrif to sign off etc... Pay my fees. Around Chicago, I'm sure you wouldn't be able to though. Can't own more than 10 round mags in Chicagoland, unless you are a thug/criminal.

View Quote

Man, you'd better brush up on the law before you do anything. Suppressors aren't some "Well, they're ok here" thing in IL. They're a no-go.

Posted: 11/25/2014 2:15:23 PM EDT

[#6]

When in doubt 1/8,

Posted: 11/25/2014 2:16:47 PM EDT

[#7]

Most of mine are 1/8 but I do have a 1/7 as well.

Posted: 11/25/2014 2:34:16 PM EDT

[#8]

I've seen in another thread that now it's starting to be seen that faster twist rates also mean the bullet stays on it's path better when it has reached subsonic speeds. So more accuracy.

Posted: 11/25/2014 3:07:05 PM EDT

[#9]

Quote History

Quoted:
I've seen in another thread that now it's starting to be seen that faster twist rates also mean the bullet stays on it's path better when it has reached subsonic speeds. So more accuracy.

View Quote

Interesting, but only relevant to a small group of very long-range shooters.

Posted: 11/25/2014 7:33:18 PM EDT

[#10]

I had a 14.5 1/9 that wouldn't shoot 75 grain but did shoot 55 well. I had a 16 midlength 1/7 that would shoot 75 grain bullets like a laser but 55 grain was average. If I was going to start shooting 68 grains and up I would get at least a 1/8 twist and 16 inch barrel.

Posted: 11/25/2014 11:50:54 PM EDT

[#11]

The mil chose 1/9 as the most accurate for m193 and m855. Groups 1/4 the 1/7 barrel. The only reason 1/7 was chosen was for the tracer. So unless you want to shoot tracers or primarly 75/77s... Aka like in hi power 600yard events... You really pretty much have no reason to go 1/7.

Oh the 1/7 barrels wear out faster too due to increased friction. So it sounds to me like you are already good to go.

Posted: 11/26/2014 1:10:01 AM EDT

[#12]

I like 1:8.

Posted: 11/26/2014 1:54:48 AM EDT

[#13]

My son and I shoot 62g and 75g from our 1/8 barrels, and they are very accurate at longer ranges, though a 1/7 would work as well.

Posted: 11/26/2014 5:47:42 AM EDT

[#14]

1/8 +5R = heaven.

I still have a pre-ban Colt lightweight in 1/7 w/box and docs; love it and will keep it. But everything else has been or is in the process of being converted to 1/8, 5R, melonited. Got a barrel siting on the floor to go into one rifle (barrel from AR Performance), and I have a 1/7 going to a buyer tomorrow because it's easier to sell than convert.

Give it some thought.

S&W makes loving 1/8 5R easy:

Posted: 11/26/2014 6:24:29 AM EDT

[#15]

Quote History

Quoted:
Twist rate correlates to bullet length, not weight.

I only use 1/7. Lets met shoot just about everything.

Are suppressors even legal in IL?

Paper punching: I'd just stick to 5.56. You'll just spend more for .300 BLK for nothing as you probably don't hunt and you "have no plans" for a suppressor.
I honestly wouldn't even consider a .300 BLK unless I had it suppressed.

View Quote

The truth here.
If you reload though it is an interesting round.

Posted: 11/26/2014 8:04:48 AM EDT

[#16]

I have a RRA with a 1/9 , POF with a 1/8 and a Noveske with 1/7 .. As just a normal weekend shooter and hunter, I basically get the same results (shot group wise) from all 3, with the exception of heavier bullets with the Noveske 1/7. The 1/7 will provide me tighter groups more consistently with heavier loads. Just my non scientific observation over time..

Posted: 11/26/2014 10:32:51 AM EDT

[#17]

1/7

Always 1/7

I might do a 1/8 Wylde chamber if I was creating a varmint gun.

ETA: that said, you won't be able to actually tell a difference 99% of the time so it doesn't really matter that much, see Molon.

[ARCHIVED THREAD] - My next AR disease---- what barrel twist

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