Confirm Action

Are you sure you wish to do this?

Confirm Cancel
Member Login
Posted: 11/11/2003 5:11:49 PM EDT
Ok I need this splaind to me.

The older Ar's had a 1 in 7 twist barrel. The were using the 55 grain bullet.

The newer barrels are 1 in 9 twist. And are using the "green" 62 grain round.

WHY did they do this. If I was to use the 62 grain in a 1/7 barrel that should give me a heaver round spinning faster with better long range placement with hopfully slightly better hitting power.

Just a thought.

If I am wrong I better stop sniffing my rifle bore cleaner (mil spec). WHHHEeeeeeee.

Link Posted: 11/11/2003 5:19:13 PM EDT
Actually the older barrels were 1 in 12 and still is excellent for 55 grain bullets, but nothing heavier. The 1 in 7,8,9, are good for 55 grain, but excellent for 62 grain and above weighted bullets. My favorite bullet for my Colt 1 in 8 barrel is 69 grain Sierra Match King VLD.
Link Posted: 11/11/2003 6:20:50 PM EDT
So if you were to use the 62 grainer with a 1/12 twist you can "burn out" the barrel in these things. Right?

So what would be the best barrle twist for non-cqb.

Can you even find barrels in 1/9 twist?
Link Posted: 11/11/2003 6:54:10 PM EDT
Most of your barrels produced now are 1 in 9, kinda one twist for all, so to speak. Do a search at RRA, Colt, Bushmaster, Armalite and you'll see. Oh, and 55 grain is maximun for stabilization in a 1 in 12 twist. Can you shoot a 62 grain bullet in a 1 in 12 barrel, heck yeah, accurate...not really, but I did stay in a Holiday Inn Express last night.
Link Posted: 11/12/2003 3:24:39 AM EDT
As usual, P806 is right on the money. Most new barrels are 1:9 twist. If you just want to shoot 55-grain and 62-grain ammo, the 1:9 is just fine.
Link Posted: 11/12/2003 1:54:28 PM EDT
P806...where did you find a Colt 1:8?
Link Posted: 11/12/2003 8:01:25 PM EDT

Originally Posted By Bradd_D:
P806...where did you find a Colt 1:8?

ooops, it's 1:7, just opened the safe and checked. OK, I take back the hair comment, ole buddy ole pal.
Top Top