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  #1  
Unread 11-15-09, 10:29
Roklok Online
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Colt 6920 vs 6721

What is the difference between the Colt 6920 compared to the Colt 6721 other than the 6721 has a heavy barrel and a 1x9 twist?
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Unread 11-15-09, 11:41
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Quote:
Originally Posted by Roklok View Post
What is the difference between the Colt 6920 compared to the Colt 6721 other than the 6721 has a heavy barrel and a 1x9 twist?


That's the basic difference. With the appropriate bullets, the 6721 will be more accurate than the 6920.






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Unread 11-15-09, 14:40
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barrel profile, twist ratio and rollmarks
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  #4  
Unread 11-15-09, 18:23
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6721 v. 6920

The previous posters nailed it (twist, HBAR).

I've owned both. Still have the 6920 and would buy another in a heartbeat.

Didn't care for the extra weight of the 6721. Not one bit.
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  #5  
Unread 11-15-09, 20:10
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Is there an advantage to an HBAR vs an m4 profile in a 16 inch rifle?
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  #6  
Unread 11-15-09, 20:41
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Quote:
Originally Posted by metroATL View Post
Is there an advantage to an HBAR vs an m4 profile in a 16 inch rifle?
Maybe in a bench rest rifle, but not in a carbine that's going to be carried and shot off hand.
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  #7  
Unread 11-15-09, 20:54
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Originally Posted by metroATL View Post
Is there an advantage to an HBAR vs an m4 profile in a 16 inch rifle?
Accuracy. The pic below shows a comparison between a Colt 16" HBAR and a Colt 16" M4 (government profile) barrel. Three 10-shot groups were fired from each barrel at a distance of 100 yards. The 10-shot groups were over-layed on each other using RSI Shooting Lab and the mean radii were calculated for the 30-shot composite groups.

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  #8  
Unread 11-16-09, 00:24
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My Colt 16" 1:9 HBAR far out shoots any of my M4 profile barrels from any maker. The weight difference means little to me.
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Unread 11-16-09, 04:22
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I have a HBAR while other 2 friends of mine have a M4profile and a lightweight....all of 3 are 16'' Colt carbines.

during a dynamic shooting match I liked the extra weight of my hbar; the lightweight carbine recoil is too different for my taste.
but the M4profile is the perfect compromise.
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  #10  
Unread 11-16-09, 17:44
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I had to trade my 6721 because my daughter needed to shoot out to 600 yards. The 1 x 7 twist handles heavier rounds better than the 1 x 9.

She used the my 6920 during her first match last June, afterthat I traded the 6721 for a RRA NM4....
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