Well, I think this is precisely why gradually increasing spacing is better. It gives the gas jet more distance to expand as it loses velocity.whiterussian1974 wrote:While agreeing w most of what you say, I must take exception w 1 aspect b/c you didn't address gas jet velocity. Yes, trapping small packets of high pressure gases early makes good sense.LavaRed wrote:Ported spacers that are smaller than the suppressor ID offer improved gas delay while also optimizing volume and reducing weight. Spacing is also critical. Note that the gases lose pressure in every subsequent chamber, so that for a given longitudinal distance, a gas particle will travel a lesser distance axially; i.e., the gas will have less tendency to expand. Therefore, the first baffles should be spaced closer, and the spacing should increase towards the exit. Not the other way around, contrary to what most do.
With your projected length and OD, I'd probably have a blast chamber of about 2", followed by some 10 cone baffles starting at 1/2" spacing and gradually increasing to 1" spacing at the end. About 1" OD for the spacers should do it. Endcaps no thicker than 1/4" each. Anything else is a waste of volume.
But, one must consider that gas jets traveling supersonic unpon leaving the barrel will enter Choked Flow conditions and must drop velocity b/f they can spread to fill the OD properly. So, if not enough linear distance b/t baffles, the core of jet will pass through into the next chamber w/o properly expanding to fill the volume.
About the spacers, I guess I can see the point of view, at least for cans with OD's of around 1.5".
Thanks for the explanation.