barrel twist rate question

[Keelty]

Holy thread revival Batman!

So for a newb like me in the AR15 scene, does it really matter whether its a 1:7 or 1:9 shooting factory plinking ammo and possible using it at the rifle match at USSA or Oil Cap?


I will probably base my ammo purchase on price not bullet weight.

 

[bettingpython]

1:9 twist rate will handle the XM193 55grain or the M855 62grain green tip ammo that sports world has available most of the time just fine. I have used both for the oil cap rifle match and at TDSA's carbine 1 class. If you plan on spending premium money for the expensive 69 thru 90 grain ammo for long range shooting in an AR then go for the 1:7 barrel twist rate.

I am assuming USSA is using some steel targets for some of their stages in which case you can not shoot the 62 grain m855 since it has a steel penetrator and will punch holes in their targets, you'll likely be shooting 55grain lead core stuff for everything.

 

[Ksmirk]

My AR I built for p-dogs I used a 1-8 twist, I COULD puff the 55gr. bullets if I wanted too (loading higher velocity) if it were ME I would just go with a 1-9 twist, you'll be fine with up to the 75gr. A-max granted you can't mag load them, MY thinking is if you want to go over 75gr. get a bigger cartridge! the 223 can do some cool stuff but I just can't see the thinking behind a 90gr SMK loaded in a 223 but that's just my opinion so take it for what it's worth!

1-9 should keep you happy with anything from 40-75gr. the 35gr are for 22 Hornet but shoot so so from a 223. Later,

Kirk

 

[Wormydog1724]

I have good groups with 50 grain JHP Federal bulk pack from Wal-Mart out of my 1:9 twist 18" Remington R-15 Chrom-Moly Barrel AND my 1:7 twist 16" White Oak Armament Stainless Steel Barrel.

 

[mmchambers06]

So for a newb like me in the AR15 scene, does it really matter whether its a 1:7 or 1:9 shooting factory plinking ammo and possible using it at the rifle match at USSA or Oil Cap?

In my opinion...hell no.

I shoot the cheapest crap I can find. Just make sure once you find a round that works for you, buy a bunch of it and stick with it. I had my rifle sighted in at 200 yards with 55 gr. Rem, but shot Brown Bear and Silver bear in the rifle match yesterday. I didn't know where I was hitting on the 300 yard stage and it probably cost me the match!

On ALL of the other stages (< 50 yards in), the slight ammo differences don't really matter. You can't blame it on the ammo on that kind of thing.

Buy whatever you find cheapest and spend the rest of your money on ammo. Getting your zero squared away and figuring out where to hold at distance is where you should spend your time.

 

[Huckelberry75]

If you plan on shooting sub-sonic, 1/7 is the way to go. Why be noisy, when you can just whisper!!!!!

 

[338Shooter]

I don't see any reason to have a 1-9 barrel. 1-7 will shoot everything the 1-9 will and more.

 

[ez bake]

I don't see any reason to have a 1-9 barrel. 1-7 will shoot everything the 1-9 will and more.

This.

Plus, more often than not, barrel-quality is far more important than twist-rate.

Some of the older barrels you would find in a couple of different off-the-shelf brands had issues with shooting the larger stuff out of a 1-9 barrel due to crappy tolerances, but I don't think a single manufacturer still has that issue (that I know of).

 

[Cadesdad]

So I am wanting to build a 24" barreled gun for longggg range shooting. Suggestions for twist and grain?

 

[edl]

http://www.6mmbr.com/223rem.html

Information on twist rate, powder, and other things. Lots of opinions on twist rate. Best advice I have seen: Go shoot the load, if it shoots well from YOUR rifle, there you go. If it does not, then keep looking.

EL