I've got a silencerco sparrow and am trying to put it on my Beretta arx .22 but have run into a small issue. I thought it would have traditional AR threading at .600 inches so I bought a .200 thread spacer. However, the threading on the ARX is apparently 1/4 of an inch to short with the spacer on so the sparrow doesn't tighten down all the way. But when I try it without the spacer in place the threads protrude 1/4 too far into the sparrow so I'm wondering which is the lesser evil until I can find a smaller spacer, leave a gap inside the sparrow and use the spacer or leave it off and let the threads protrude 1/4 of an inch inside the can? Would either of these two options pose any significant threat to a stainless steel can like the sparrow or am I overthinking this?