there is an ongoing debate --
to crimp or not to crimp
I do not crimp bottle neck cartriges, even if the bullet has a crimping groove
the neck tension is enough to hold the bullet, if it does not check the neck
tension
there are times to crimp ( tubular magazines, very high recoil )
read your reloading manual
none of my bolt action or semi automtic rifles have any type of
problem with these uncrimped cartriges ( I have checked and measured )
( 223, 5.56X45, 7.62X39, 6.5X55, 303, 7.62X54R, 308, 7.62X51, 30-06,
7.92X57 )