upon how quiet you want it to be, how much service life you want between mandatory cleanings of the can's baffles,and whether ornot you want to bother with putting a shot of WD-40 and then some water into the can, before firing the gun. The WD-40 is to reduce the corrosive effects of the water inside of the can. The water makes the can considerably more effective at reducing the blast and the flash. A "sleeved" can-design, using a 3/4" OD tube,inside a 1" OD tube, works best, the rear half of the inner tube being vented into the area between the tubes. Then, the bottom, real half of the outside tube is slotted, to vent into and (empty, no baffles) "underchamber", which helps make the can more efficient, while still leaving the package be a CCW OAL. It's also feasible to rig a slidelock on the right side of the gun, so that the slide has to be manually cycled. Quite a bit of noise comes out of the ejection port of the autoloaders, you know.
Such a 14oz, 9" long gun is lw,compact enough to ALSO let you carry something like a Kahr PM 9mm, in a front pants pocket. 6" long, 15 ozs, and ANY 9x19 can be rechambered to 356 TSW and offer 600 ft lbs,and AP perfomance. Why have ONLY noisy gun,or ONLY a feeble, canned .22, hmm? With both such guns, and with concealable armor,you can be pretty far ahead of anybody you are likely to run into, regardless of where you are or what you are doing.
Add REAL ability with those pistols, and black belt ability with the "natural weapons", and you can blend into any crowd, yet be ready to handle a pair of jbt's if you have to do so.
Making the M21 a kit gun takes about 10hours, and so does making and testing its can. It's not a job for a hack with a cutting torch.
Such a 14oz, 9" long gun is lw,compact enough to ALSO let you carry something like a Kahr PM 9mm, in a front pants pocket. 6" long, 15 ozs, and ANY 9x19 can be rechambered to 356 TSW and offer 600 ft lbs,and AP perfomance. Why have ONLY noisy gun,or ONLY a feeble, canned .22, hmm? With both such guns, and with concealable armor,you can be pretty far ahead of anybody you are likely to run into, regardless of where you are or what you are doing.
Making the M21 a kit gun takes about 10hours, and so does making and testing its can. It's not a job for a hack with a cutting torch.