Best twist for 40gr bullets in a 223 Rem

[RonS]

I’m thinking of building a bolt gun/fun gun for the grandkids and folks who want to learn. I have about a couple thousand 40gr bullets just collecting dust. Which would be ideal a 14 or 12 twist? I have 9, 8 and 7 twist barrels for heavy bullets and a 12 twist AR-A2. And what length barrel would you suggest?

 

[Mark M.]

22" barrel, 14 would be best for 40, if it were me I'd make it a 12

 

[rockhound78]

I would also make it a 12" twist.

 

[AckleymanII]

Zero freebore reamer, most important vs twist rate! 12-14 very forgiving on large nodes that will cover a grain or more on a tune.

 

[338 dude]

I’m thinking of building a bolt gun/fun gun for the grandkids and folks who want to learn. I have about a couple thousand 40gr bullets just collecting dust. Which would be ideal a 14 or 12 twist? I have 9, 8 and 7 twist barrels for heavy bullets and a 12 twist AR-A2. And what length barrel would you suggest?

 

[338 dude]

I’m thinking of building a bolt gun/fun gun for the grandkids and folks who want to learn. I have about a couple thousand 40gr bullets just collecting dust. Which would be ideal a 14 or 12 twist? I have 9, 8 and 7 twist barrels for heavy bullets and a 12 twist AR-A2. And what length barrel would you suggest?

 

[Hotshot]

16 would be the best for 40's only. Go 12 because things change.

 

[sundance]

I have used 12 twist Kriegers in my 223 ackleys for 30+ years. Always worked really well with 40 grain Vmax bullets. Worked well for me, not so much for prairie dogs.

 

[TAJ45]

Ah yes, those rotational forces make the fur fly . . . Literally and fjguratively - oh yeah.

 

[David Milisock]

Scientifically speaking as long as it is fast enough to stabilize it does not matter if it's a faster twist.
The caveate being a quality projectile, a poorly balanced projectile seems to suffer more with a fast twist.
I have a 1 in 12 shoots 40's well. My 1 in 7 shoots 40's well, the bullet is a Hornady VMAX MOLY.

 

[drover]

You will likely see good accuracy with the 40's using a 12 twist, that also gives you the option of shooting 50's, 53's, 55's.etc, where the 14 twist will be more picky when going to heavier bullets.

I shoot 40's near exclusively in my 223's which are 10 twist and all shoot sub-1'2" five shot groups.
.
drover

 

[pintopete]

RonS, most all of my .222's are 1:14 twist. IMO they all shoot 40 - 53 gr bullets well, 55's not as well. Most of my barrels/rifles are factory Remington, but the same is true for those with quality stainless (Hart). Recently I ordered a new barrel in 1:13, but haven't received it yet. When choosing, I always keep in mind that once ordered, twist can't be changed. Velocity and bullet weight can be changed, but once twist is done, it is done. I know you asked about .223, but the two are similar in this regard, especially for 40 gr bullets. I agree with others...go with 1:12 for a .223 for what you described.

Good luck, Peter.

 

[RonS]

Thanks to everyone for your thoughts. I do have a 222 with a 14T but I think it is worn out, the throat is at about 0.075”. Plus I’ve had the crown re-cut twice and it still shot the 40’s at +1MOA@100yds. The 40’s did shoot very well in my 12T AR and it also shoots 52 and 53’s very well. I get the reason some recommended a 12T but I want a bolt gun dedicated to the 40’s @ +3500 fps and (hopefully) accurate. Now I can’t decide wether to use my worn out Rem 788 222 or a 700 action that’s collecting dust...

 

[A_Gamehog]

12 twist as stated before
40 grain bullet
AA2230/X-Terminator powder.
IMR 8208 close second in accuracy.
CCI400 primers
Lake city brass
Proven accurate load
3500+ FPS easily

 

[Lefty2506]

My flat top upper has an 8 twist 22" barrel from Rock River chambered in .223 Wylde. I've worked up 40 gr VMax loads with multiple powders that produced groups that are 1/2" or better @ 100 yds.