A friend of mine shot his 308 blr last year and there must have been some dirt in the muzzle it bulged out the end of the barrel at the muzzle so I was going to shorten it to where it is still good and recrown it but it is a short barrel what is the minimum lenght from the muzzle to the breach if I end up to short for none restricted could I install a muzzle brake on it to lenghten it to leagal size?