Quiet Bore 22LR Form 1 Review : NFA - reddit Quiet Bore 22LR Form 1 Review. This can has been a solid performer. Started life as a Quiet Bore 22LR kit I made into a Form 1 can after receiving my stamp in 11 days total. It has an aluminum tube and end cap, 4140 steel mount, and titanium K-baffles. It weighs 3.77 oz and is fairly compact (5.25" OAL and 1" OD).