in rear of 223 can has to be welded together. if it aint, the blast and heat will compress the donut screenwire baffles forward enough, to let the washers tip over, into the path of the bullet. A hunk of aluminum rod, machined into shape of a bunch of "tulips", in line with each other, vented out from the bullet-tunnel, and ALSO vented forwards, is the best answer to making the hottest, highest pressure, dirtiest gases go out into the "sleeve" area of the can. PITA to make such a gas-diverter, tho.