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Posted: 7/19/2010 2:48:46 AM EDT
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I was reading through a few weeks ago and saw a claim that a certain brand barrel perhaps with polygonal rifling was achieving the same velocities with a 14.5" barrel as with a 20" barrel using the same ammunition. I have been using the search feature without success. Does anyone else remember what brand of barrel this is? Has anyone tested the claims with their own chronograph?
Grunt |
| The only way my 18" WOA SPR gets over 2700fps with my hand-loaded HOT 77gr SMK's is with a Tubb carrier weight installed. Same handloads through a 16" DD bbl clock 85-100fps slower with the cws installed. Mk262mod1 clocks around the same without the CWS installed. Tried my hand-loads once without the CWS and blew out two primers. The CWS is an awesome invetsment if you want to squeeze the most velocity with handloads. I don't for a second believe ANYONE can get velocities within 100fps between ANY 16" and 20" barrel. |
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Quoted:
I've read that Noveske SS 14.5" barrels (with polygonal rifling) will produce the same velocity as 16" barrels. I would guess that someone quoted this incorrectly. A 14.5" will be a lot closer to a 16" than a 16" will be to a 20". The longer the expanding gasses are trapped, the higher the velocity. It's impossible to make a shorter barrel shoot as fast as a longer barrel using the same ammo. |
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I agree with the suggestion that the chamber matters, but I think the test would have to be with the same barrel chambered three different ways to have validity. Along with the chambers being of different dimensions, it's safe to assume the tolerances of the barrels are different as well, match to C/L utility grade. |
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