A question about short barreled carbines...

[spoonkilr]

I remember in a thread, ages ago, people were discussing the extra loud gunfire that comes from firing short barreled carbines, like the XM177E and another few predecessors or variants of the M4. How does chopping the barrel down make it louder? (Sorry if im annoying you with my n00bness.)

[Jippo]

Cartridges are always loaded for certain optimum barrel length, and that is the full rifle length barrel in most cases. Therefore when such round is fired from shorter barrel the pressure inside still remains at higher level when the bullet escapes barrel. This pressure manifests as louder 'bang' when it is released.

Also usually powder has not time to burn completely, and the remainder of it burns outside the barrel giving additional sound and flash.

It is possible to load cartridges for carbines that do not produce any more flash or sound (hell you can make them subsonic if you like) than normal round from rifle lenght barrel.


-jippo

[spoonkilr]

Thanx alot jippo, that one has been bugging me for a while.

[akmarksman]

You run into reliabilty issues as well..using a shorter barrel is ok for indoor..but the M855 cartridge performs well in a M16A2/3/4 with a 20" barrel.
Hence the un-official adoption and use of the MK262 mod 0 in the M4

[Frens]

if you questions about ammo, short/long barrels then check http://www.ammo-oracle.com