View Full Version : How to tell the sized of bolt rollers(headspace?)

August 14, 2015, 21:11
How do I tell the size of the rollers on a bolthead that fits a HK91?I ask because I got a new bolthead and it would not fit the rifle but it fit the carrier fine,rollers seem fatter and are unmarked so I would like to get the size that fits for extras in case of a failure in future.Thanks in advance.

August 15, 2015, 08:32
Standard 8mm rollers are not marked all of the others are marked + or - and a number for example +2. As the rifle is used and wears you will need different size rollers. Do you know how to check the bolt gap ? Maybe someone with more expertise will chime in

August 17, 2015, 16:59
Try this link: