pressure ring on bullets

[lpreddick]

been reloading for about ten years and am now getting serious about details. what is it about pressure rings on bullets? my first encounter with this was years ago with a 110 gr MEF .25 cal from berger...the base of the bullet was .001 larger than the dia. of the bullet and was a problem if seated below the neck-ahoulder junction...it fell into the case! bart's seems to be the only bullet maker that mentions these rings. not to make a list, but some high b.c. 6mm bullets have them and some don't. i read that they are part of the bullet making process and not intentional. i can't find much on the subject and am curious. being larger in diameter than the bullet, is there a problem when seating below the neck-shoulder juncture? do they have a useful function? if the bullet is still in the neck and is seated into the lands, does this give a two point grip on the bullet? what do they mean? if i can see you, i can touch you! BANG