will a 9 twist stabilize 65 gr sierra in a .223

johninok

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Minuteman
Jul 6, 2011
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central ok
Have a 9 twist barrel I want to use for a .223 build, but I want to be relatively sure that it will work with the sierra 65 gr game king bullet. have a ton of these, and the rifle will be a field/hunting set up. Thanks for any help.
 
Re: will a 9 twist stabilize 65 gr sierra in a .223

I've shot a somewhat similar bullet in 1:9's with Great results; Speer 70gr SP. It's short for it's weight. I really like that bullet.

Also, I've had good results w/ 69gr match and even 77gr match. I tried loading some 75gr amax for single feed through a 1:9 and it would not stabilize. 100yd groups showed some keyholing on a well backed target.
 
Re: will a 9 twist stabilize 65 gr sierra in a .223

I have a Remington LTR and a Remington Tactical, both 1-9 twist, and they both will stabilize the Sierra 77SMK out to 300yds. Lucky I guess.
 
Re: will a 9 twist stabilize 65 gr sierra in a .223

Yep, my 1-9 16" shoots Hornaday 75 BTHP match bullets seated mag length filled with Varget real nice.


Edit: With 69gr. Sierras I run win 748, also shoots real nice.
 
Re: will a 9 twist stabilize 65 gr sierra in a .223

Armalite states that their 1:9 twist barrels will stabilize 52-69 gr bullets. Best way to see is to measure bullet length with a caliper and plug in the info into the miller twist stability formula.

Most twist recommendations are made on lead core, copper jacketed bullets. Copper solids, bizmuth, aluminum, tungsten and steel (and depleted uranium) will fly different do to dimension difference in similar weight projectiles.
 
Re: will a 9 twist stabilize 65 gr sierra in a .223

69's work great. I tried pushing the 77 smk. Barely holds on when it's warm and keyholes when it's cold. I play it safe and it will shoot anything up to 73g, but 68 hornady's and 69g smk's are cheap and shoot great.
 
Re: will a 9 twist stabilize 65 gr sierra in a .223

Should be fine - my LTR with a 1/9 will stabalize the 75 AMAX, so the 65 Sierra should be no problem.
 
Re: will a 9 twist stabilize 65 gr sierra in a .223

I have used the 65 game king in my factory 9 twist Remington tactical. No issues with stability and checking JBM with my data it has a rating near 1.9 at zero degrees and even with a 10 twist it is showing 1.6 so you are good to go.
 
Re: will a 9 twist stabilize 65 gr sierra in a .223

Ive seen some 9 twist barrels stabilize the 77gr SMK's with the right load.. But its has been the exception, not the rule..

You will be fine with up to the 75gr bullets, usually.. Steer clear of the VLD or SST's though.. They are a bit too long for the 9 twist in that weight.
 
Re: will a 9 twist stabilize 65 gr sierra in a .223

I had a bushmaster AR service rifle upper for years with a 1:9 twist...
Stabilized Hornady 75 Match bullets just great. (about 1.25" groups consistently at 100yds - plenty good for what I was doing at the time)
Wouldn't stabilize a 75 Amax worth beans (10" groups)
Sierra 80's? Forget it.

So, yeah... as long as your barrel is actually 1-9", and not 1-9.25", anything Hornady 75 Match length or shorter should work fine.