Quote Originally Posted by Alpha2 View Post
A can won't know the difference between 5.56 and .223, 'cause, well, there isn't a difference. Same boolit.
Pretty close, usually.

The grain of truth to the internet rumor is that a common "5.56 round", the M855 and its M856 tracer brother, may not stabilize out of older guns with a 1x12 rifling twist, such as original Colt SP1 rifles and anything made from an original M16 or M16A1 demiled parts kit. If the bullet's not stable, it can be dangerous to fire it through a suppressor for fear of a baffle strike. A baffle strike can range from an annoyance that erodes away the edges of your baffles like little kids nibbling their way around the edges of cookies, to a full-on catastrophic collision that rips your suppressor open and spills its guts out like a semi driving over a banana.

With .223/5.56 the suppressor issue is stabilization, not bore pressure or cartridge specification.

The other way around, firing .223 or 5.56 through a 22lr can is a pressure issue, because the rimfire suppressor isn't made to handle the gas pressures of the rifle round, and may pop apart like putting a firecracker in a soda can.