S&B tight brass pocket and how to fix it

I spent few hours doing brass prep today and thought I’d share this.

It’s well known that S&B brass has very tight primer pockets. Unless you are very lucky… In fact, seating a primer in a fired case could (has for me) crush the primer.

Not all is lost however. (a) There is a primer swaging kit from RCBS. It will work, however in this case (S&B brass) it wouldn’t benefit from it, other than shorten the life span of the case. I thought I’d mention and eliminate this approach, because this would be the first port of call for a lot of people. (b) Cut a small bevel on primer pocket mouth using a Chamfer & Deburring tool.

I found that this is the best solution. I have a primer pocket swaging kit too, however it’s better suited for crimped brass, not tight pockets that are still more or less in spec… We want to keep it tight, just not primer-crushing tight.

So, using the pointy end, pass over the pocket a couple of times (twice does it for me on 308 and 223 brass). This will add a bevel on the primer pocket mouth and primers will seat perfectly.

Have you tried a primer pocket uniformer?

No. I never had a need for one. And I never had an issue with primers or primer pockets. I needed a swaging kit, because I had lots of once fired Hornady brass. Buying a swaging kit was cheaper than replacing brass. Other than that, I really don’t do anything to primer pockets.

Once I had an issue with primers and hang-fired, but I suspect it was poorly stored 90 year old ammo LOL.

Was just thinking that the primer pocket uniformer might make it easier to seat the primers. It will remove a little bit of brass if it needs it.

Well, it really is just a smaller version of Chamfer & Deburring tool I posted above. What I posted above works perfectly well. Did lots of S&B brass like that before, i.e. this is not the first time I am discovering this - tried and tested.

I’d imagine that Primer Pocket Uniformer fits a lot better and would deliver a more consistent result. However, in my case, this is just a milsurp plinking batch of brass, so near enough is good enough, as long as it works…

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@juststarting i had the same issue with S&B 223 cases. I came up with the same solution but different tool . I used a 3 cornered scraper.

You can easily make one from a triangular file.

It seems that the problem that has been described is to do with the primer pocket diameter which is compromised by some form of swaging that reduces the diameter slightly at the upper edge.
A primer pocket “uniformer” generally only cuts material from the bottom surface so that it is a consistent depth WRT the base.
I think OP has found a cure with judicious use of a chamfer tool to relieve the swaging/crimping.
There is some military stuff that’s as good as “staked” to keep the primer in.