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sfguyhere
03-04-2010, 11:50 PM
Hi there,

Any recommendations for ammo? I recently purchased a Colt 6940 AR 16" with a 1:7 twist.

Does anyone have a similar rifle and could recommend a good grain weight for 100 yard accuracy? In case the zombies come.

Also, do you have a recommendation for decent surplus ammo given the barrel, something to burn up at the range?

Any help would be greatly appreciated.

dakobster81
03-05-2010, 12:16 AM
shoot 55 grain stuff for plinking, for the good stuff look at the higher grain bullets up to the 77 grain stuff, more expensive but its the good stuff, a 1:7 twist is good for anywhere in that range (55-77 grain) also, I think all ammo is fair game for zombies ;) also, nice rifle choice

here's a link all about 5.56 and .223 ammo: http://ammo.ar15.com/ammo/

J_Rock
03-05-2010, 12:21 AM
shoot 55 grain stuff for plinking, for the good stuff look at the higher grain bullets up to the 77 grain stuff, more expensive but its the good stuff, a 1:9 twist is good for anywhere in that range (55-77 grain) also, I think all ammo is fair game for zombies ;) also, nice rifle choice

I would say 69gr max with a 1:9. Not all 1:9's will stabilize the 75/77gr bullets.

dakobster81
03-05-2010, 12:22 AM
I would say 69gr max with a 1:9. Not all 1:9's will stabilize the 75/77gr bullets.

that was a typo, edited to say 1:7

FMJBT
03-05-2010, 12:23 AM
62 grain SS-109 should run pretty well out of that rifle, especially if you can get some manufactured by Lake City. Best accuracy with a particular bullet weight/type will vary from barrel to barrel, but generally speaking the 1-7 twist rate will do better with heavier bullets. 69 and 75 grain HPBT's should do pretty well for you. For budget shooting, I'd suggest ammo manufactured by Prvi Partizan. They make a decent shooting version of SS-109 (Green tip 62 grain FMJBT), as well as 69 and 75 grain match loads that perform extremely well and sell for quite a bit less than comprable loads from Federal and Black Hills.

J_Rock
03-05-2010, 12:28 AM
Hi there,

Any recommendations for ammo? I recently purchased a Colt 6940 AR 16" with a 1:7 twist.

Does anyone have a similar rifle and could recommend a good grain weight for 100 yard accuracy? In case the zombies come.

Also, do you have a recommendation for decent surplus ammo given the barrel, something to burn up at the range?

Any help would be greatly appreciated.

Honestly your barrel will can pretty much shoot anything thats on gun store shelves. If you want accuracy get ammo that says MATCH on the box.

Cody
03-05-2010, 12:43 AM
Honestly your barrel will can pretty much shoot anything thats on gun store shelves. If you want accuracy get ammo that says MATCH on the box.
+1
I believe that bullet type is more important than weight with 1:7/1:8 twist barrels when it comes to accuracy.
Check out my other post:

.223 Ammo testing (http://www.calguns.net/calgunforum/showthread.php?t=272805)

-Cody

Peter W Bush
03-05-2010, 1:16 AM
Just get some Mk262 and get it over with :gunsmilie:

cleanguy46
03-05-2010, 7:12 AM
62gr FMJBT run well out of a 1:7. I have a 16" Noveske Recce 1:7 and it loves this round, but it shoots 55gr FMJBT almost as well.

sfguyhere
03-05-2010, 9:24 AM
Thanks for all the info!

mif_slim
03-05-2010, 9:48 AM
Yup, it's not on grain of bullet, it's bullet construction. Reason most people get it confused is because the steel core bullets will need to be longer to retain the 62gr bullets. This is because lead is heavier then steel so the bullet construction is longer which then needs the extra twist to stabilize the projectile.

If you look at a barnes full copper 55gr bullet compared to a normal 55gr fmj you will see that it is much longer. A 55gr full copper bullet will need a higher twist rate compared to a lead projectile. But for your twist any ol' millitary round will do. In the same caliber of course.