Thanks for the reply. My main reason for wanting to suppress my r-15 is for predator hunting. I just don't know how putting a 6 or 7" can on my already 22" barrel is gonna work. Might feel too long.
That's for you to decide. The short barrel craze is not something I am into. There was a time when military sniper rifles pretty commonly came with barrels that were or were close to 30'' A long barrel does not bother me. But I know some people who claim to feel a difference between 22'' and 24'' and prefer 22''