Hi all - any input on this: What's the recommended twist rate if I were shooting 55 gr FMJ practice rounds? Also some 55 gr v-max Hornadys for coyotes? (It seems like the old standard was 1/12, the new standard in AR's might be 1/9 ??)
My Sig556 is 1:7 and shoots 223 55gr perfectly well/accurately at 50-100 yards. Have not tried it further.
An excerpt:
[FONT=Times New Roman, Times, serif]Opinions (Pro and Con):[/FONT]
[FONT=Times New Roman, Times, serif]1:9 is best. Why? Flexibility. It doesn't seem to have any problems throwing M856 tracers around, unless it gets really cold, it wears better than 1:7 and it stabilizes more rounds than 1:12. Additionally, 1:9 rifles, even Mil-Spec chrome chambered and barreled, can attain 1.0-2.0 MOA out to 300+ meters.[/FONT]
[FONT=Times New Roman, Times, serif]No, 1:7 and 1:8 are the best. Why? Accuracy. For heavier and longer rounds during competition shooting, 1:8 and 1:7 twists are the best for heavy 77-80 grain rounds that I use to shoot competitively at 500-1000 meters. Who needs to shoot tracers anyhow? More importantly, heavier rounds are showing very good results in terminal testing and are proving to be much better defensive rounds.[/FONT]
I currently have three .223's, one 1:14 and two 1:12, both of which stabilize 55 grainers just fine. 1:12 does fine up to and including Nosler 60 gr. It is my understanding that 1:9 and tighter twists were developed for long-for-caliber bullets; 69 grains and above. Regards JN
Both my Bushmaster and my Savage have 1:9 twist barrels. They both sling 55 grain rounds accurately out to 100 yards. I have not had the oppurtunity to shoot at longer distances.
the heavier the bullet, the more twist you need to stabilize it. 1:9 twist seems to be the "norm" because it will do well with a wide range of bullet weights. 1:12 twist will probably do best with 62gr. and less, but might struggle with heavier bullets at longer ranges. My M&P15 has 1:9 twist