Is it energy, velocity or both that makes the comp work?
Is it energy, velocity or both that makes the comp work?
The short answer is that it's gas dependent.
The longer answer is that porting will work by directing gases opposite the direction of muzzle flip, so the porting effect will increase with increases in either gas mass or velocity.
For short-recoil pistol comps, it's a little different in that the gases also act on the inside-facing walls of the port, and work to hold the barrel and slide locked together longer, which means that once the gun unlocks, it's unlocking at a lower pressure, decreasing slide velocity. This is in addition to gases acting opposite the direction of muzzle flip. Again, increases in gas mass or velocity increase the effect.
To get maximum effect from these things, slower-burning powders have higher pressures, and therefore higher gas velocities, out towards the muzzle. Thus, the example of the 38 Super or 9x23 Open gun that's running at Major Power Factor with slow-burning powders that can be basically neutral in recoil with 10-lb recoil spring, or if mis-tuned, actually recoil downwards.
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