Primers fitting loosely in RST shells.

[J.B. Books]

Originally Posted by Cory Rams

I tried both federal and Winchester 209 primers in a couple of spent 2 7/8” RST 10 gauge hulls today. I can push both brands of primers completely flush with my thumb. Any tips or suggestions to get primers to seat with some holding force in RST hulls?

RST uses Cheddite hulls and they most likely get them primed with Cheddite primers. Cheddites can be slightly larger than American made 209 primers. There is a tool you can buy to swage the primer pocket tighter. A trick I have used with undersized 57 primers is to cut a length of plastic straw almost the same length as the narrow part of the primer. Slide it over the primer before seating the primer. The straw should provide enough friction to hold the primer in place. Be careful to not cut the piece of straw too long so that it covers the flash hole as that will most likely lead to a dud.

http://parkerguns.org/forums/showthr...ht=primer+hack

[Cory Rams]

Originally Posted by Pete Lester

RST uses Cheddite hulls and they most likely get them primed with Cheddite primers. Cheddites can be slightly larger than American made 209 primers. There is a tool you can buy to swage the primer pocket tighter. A trick I have used with undersized 57 primers is to cut a length of plastic straw almost the same length as the narrow part of the primer. Slide it over the primer before seating the primer. The straw should provide enough friction to hold the primer in place. Be careful to not cut the piece of straw too long so that it covers the flash hole as that will most likely lead to a dud.

http://parkerguns.org/forums/showthr...ht=primer+hack

Thanks! I knew there had to be a to fabricate for a tighter fit. I have 30 shells and probably will switch over to brass after I wear them out so I’ll try adding a straw instead of investing in a tool that I’ll end up never using again after my handful of rst cases wear out.

[edgarspencer]

Another member and I were just discussing this yesterday, and I find the Cheddite primers are anywhere from .0005" to .001" larger the a W209.
As Pete says, a primer pocket tool is the fix.