Posted: 4/9/2004 9:52:41 PM EDT
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How much of a difference does barrel length make. What is going to be the difference in velocity using the same ammo between: compact and full sized auto's in 9mm, .40, .45 auto. 2 inch 4 inch and 6 inch revlovers in .357mag and .38 Will the shorter barrels in all calabers listed above allow for enough velocity for the bullet adequately pennetrate and expand? |
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there was a thread posted on this and i think it was in the ammunition forum on the ar15 forums. seems like i remembered there is a loss of velocity (naturally) with the shorter barrels but with certain loadings and rounds (.45 acp, 230 fmj comes to mind) it did not adversly affect the terminal performance at "reasonable ranges". it varies some for each one. some of you here may be able to offer more definite answers. i'll see if i can find the older thread. (update)couldn't find it - but i think the hotter +p loadings with lighter bullets suffered the most from muzzleblast increase and reduced performance while the heavier roundsat more modest velocities did not see as much of an impact. could be due to the inertia of the heavier round and just not shedding the energy as fast. honestly though, at normal ranges for personal defense with a pocket gun, i don't think it would be that much of a factor. others may know better. |
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Velocity loss seems to be a standard of about 50f/p/s per inch loss off of a 4" barrel. Thus a 2" would lose 100f/p/s using the same ammo. There may be some ammo designed for short barrels but I'm not aware of any. The loss of velocity in a .357mag shouldn't be a factor, IMO. 38spl, it may be a factor since it's a lot slower to begin with. Some folks think that with these baby semis out there it may be best to stick with FMJ for feeding. I agree. My .o2 |
Yes, mostly for feeding. The baby semi's have a different feed angle than do their full size brothern. I've read of many a gun mfgr engineer pulling out his hair over this one problem. There's also the concern of losing f/p/s as HPs are designed for specific speeds. Losing 100 f/p/s HAS to have some sort effect, IMO. I used FMJs for defense loads for years, still do in my 1911. My .o2 |