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Velocity Question

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Old 09-25-2010, 06:12 AM   #1
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Default Velocity Question

Forgive me for what may be a stupid question but I have no experience with autoloaders so you'll have to put up with my ignorance!

Does the cycling system on a semi-automatic firearm rob the bullet of velocity when compared to the same load being fired out of a bolt gun?? If so is there any noticable difference in on-target bullet performance or tragectory?

I would have thought that seeing as though some of the energy that usually propels the bullet out of the barrrel now cycles the action to prepare for the next shot, the bullet would leave the barrel noticable slower. Or is the reloading action so effficient that there is negligable velocity difference between semi's and bolt guns?

Thanks for your help, I wish I had access to an AR, SKS et al to find out for myself, but unfortunately I don't so you guys are my next best option!

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Old 09-25-2010, 01:24 PM   #2
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No, there's no loss of velocity. In a semi-automatic, the bullet is long gone by the time the action begins to move.

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Old 09-27-2010, 04:38 PM   #3
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In a gas operated rifle, there is a slight loss of pressure through the gas port. This will lead to a slightly lower velocity. The loss will not be significant. Barrel length and internal barrel finish will likely account for more difference.
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Old 09-30-2010, 01:57 AM   #4
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there is a loss yes
it does affect the accuracy
noticeable would have alot of factors that were depending on....
grain of the bullet, type of powder (ball or stick), length of the barrel, type of the rifling, and etc..
i think to best research this topic yourself i would look at 7.62nato (.308 win) because of the diverseness of the round as well as the ballastic info that is available.
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