1:7 twist... about to take the plunge - please read scenario and advise

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[ARCHIVED THREAD] - 1:7 twist... about to take the plunge - please read scenario and advise

Posted: 9/29/2004 9:26:46 AM EDT

OK, I am on the brink of committing to a post ban Colt 6601 from a buddy of mine, to be used primarily as a CMP/highpower type rifle. It has a 1:7 twist, 20" barrel.

I HATE having to inventory a variety of ammo, so if I buy this sooner than later I'll be looking for a 16" carbine (or an upper for a lower I have around here) in 1:7 so that I have the ability to shoot/inventory X193 or BH 77 gr through either gun.

Who makes a good 1:7 carbine with all the goodies- telescoping, flash hider, and the absolutley mandatory lug ;) ?

Furthermore, am I missing the boat? I'm not a very good rifleman - I'm buying the 6601 to help improve my skills. Should I just be buying a 1:8 twist Rock River and not worrying about the 20" 6601 or the 1:7 carbine at all?

Help!

Paul

Posted: 9/29/2004 9:34:02 AM EDT

[#1]

Quoted:
Who makes a good 1:7 carbine with all the goodies- telescoping, flash hider, and the absolutley mandatory lug ;) ?

Colt

Bushmaster (you will need to 'special order' the 1:7 twist M4 upper.)

CMMG

Posted: 9/29/2004 9:58:46 AM EDT

[#2]

Thanks for the reply - Colt is making new rifles with the 1:7 AND all the evil features?

Posted: 9/29/2004 10:02:10 AM EDT

[#3]

Quoted:
Thanks for the reply - Colt is making new rifles with the 1:7 AND all the evil features?

If you can find a LE6920 within reasonable price, I suggest you pick it up. It's got "all the evil features" and the 1:7 5.56 NATO barrel you are looking for.

Posted: 9/29/2004 10:35:04 AM EDT

[#4]

Thanks! Also wanted to make sure i understand correctly -

1:7 can fire 55 gr bullets, i.e. X193, without any issues and no meaningful loss of accuracy vs. a 1:8, 1:9...

Thanks again... Part of me says just buy some RRA with a 1:8. Not sure why I fear the 1:7 so much, just heard it limits you from a few trustworthy sources.

Paul

Posted: 9/29/2004 10:49:27 AM EDT

[#5]

Quoted:
Thanks! Also wanted to make sure i understand correctly -

1:7 can fire 55 gr bullets, i.e. X193, without any issues and no meaningful loss of accuracy vs. a 1:8, 1:9...

Thanks again... Part of me says just buy some RRA with a 1:8. Not sure why I fear the 1:7 so much, just heard it limits you from a few trustworthy sources.

Paul

All questions will be answered by the Ammo Oracle

Posted: 9/29/2004 11:06:39 AM EDT

[#6]

Military uses 1/7 twist!

Posted: 9/29/2004 11:35:54 AM EDT

[#7]

Quoted:
Not sure why I fear the 1:7 so much, just heard it limits you from a few trustworthy sources.

Paul

I am by far an expert but that quote might be backwards.. 1:12 limits the most as 55 grns only, then 1:9 handles for the most part up to 68 grns and occasionally some people hav hade 70+ luck in the 1:9 but 1:7 handles the 77 grains with no problems.....

Posted: 9/29/2004 1:34:29 PM EDT

[#8]

Quoted:
Thanks for the reply - Colt is making new rifles with the 1:7 AND all the evil features?

Yes you order a LEO rifle.

Posted: 9/29/2004 2:21:26 PM EDT

[#9]

Quoted:
Quoted:
Not sure why I fear the 1:7 so much, just heard it limits you from a few trustworthy sources.

Paul

I am by far an expert but that quote might be backwards.. 1:12 limits the most as 55 grns only, then 1:9 handles for the most part up to 68 grns and occasionally some people hav hade 70+ luck in the 1:9 but 1:7 handles the 77 grains with no problems.....

What I meant was that you have to use HEAVIER than 55 gr bullets. If that isn't the case, then I'm a happy camper.

So, 55 gr isn't a problem out of a 1:7 in any way, shape or form?

Paul

Posted: 9/29/2004 2:53:27 PM EDT

[#10]

Quoted:

So, 55 gr isn't a problem out of a 1:7 in any way, shape or form?

Paul

Not a problem at all.

Posted: 9/29/2004 3:25:10 PM EDT

[#11]

55 gr has no problems w/ stablization w/ the 1:7 barrel, at all. What more beautiful is that the 1:7 twist barrel can stablize heavier rounds than the 1:9.

Posted: 9/29/2004 5:08:32 PM EDT

[#12]

Thanks everyone - I'll be testing it out soon!

Posted: 9/29/2004 5:27:56 PM EDT

[#13]

I am pretty sure that a lot of the time 50 grainers will break up out of a 1/7 20......The 1/7 at 20" will spin 'em too fast.... v e l o c i t y..........

Posted: 9/29/2004 8:09:30 PM EDT

[#14]

Every thing I have read about twist rate vs weight recommend not using lite bullet in 1/7. 62grn min. 55grn may breakup in mid air. 1/7 barrel also supposly wear faster.

I think orginal Stoner A1 was 1/12 for 55grn. Design to be barely stable so it will tumble in soft tissue. 1/9 was a middle ground for civilan shooting needs. hinking.gif

Posted: 9/30/2004 9:51:45 AM EDT

[#15]

OK - what about the 1:8??? RRA offers those in stainless... better compatibility with 55 gr and won't wear as quickly?

Paul

Posted: 9/30/2004 10:17:26 AM EDT

[#16]

Quoted:
OK - what about the 1:8??? RRA offers those in stainless... better compatibility with 55 gr and won't wear as quickly?

Paul

The 1/7 will be just fine for 55gr and the extra wear will not be noticable unless you need to be shooting .25 MOA on a consistant basis.

Though if someone would make a 1/8, 4150 fully chrome lined barrel with a 5.56 chamber and a M4 barrel extension I'd buy one for sure...

Posted: 9/30/2004 10:18:50 AM EDT

[#17]

Quoted:
I am pretty sure that a lot of the time 50 grainers will break up out of a 1/7 20......The 1/7 at 20" will spin 'em too fast.... v e l o c i t y..........

hehehehehehe, anything lower than 50gr will come out like a mini-shotgun from a 1:7 twist barrel.

Posted: 9/30/2004 10:49:08 AM EDT

[#18]

Not entirely true, even though Nosler Balistic Tips may explode nicely on vermin at range, I find them to be constructed heavily enough that they will hold together. Maybe if a 22-250 was spanking them out of a 1:7 it would be death to the little 40grn bullets.

The one bullet that seems to be the most fragile out there is the Speer 50grn TNT, that is truely a fragile bullet and I wouldn't expect it to hold together for junk.

52 and 53grn match hollow points should hold up nicely.

[ARCHIVED THREAD] - 1:7 twist... about to take the plunge - please read scenario and advise

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