Primer pocket uniformer question

[gregj]

I usually chuck the small pocket reamer into my benchtop drill press (for 223 brass), put it on low speed, and go at it. I noticed on a piece of brass the pocket seemed to be cleaned up at an angle. This made me wonder how important it is to ensure the case is inline with the reamer (concentric)? Almost all the reamers I've seen are hand held, which would make it almost impossible to insure the pocket is square to the case. If a pocket isnt cut square, the primer will not seat square. Or am I missing something ......

Also, will holding the case by hand will be close enough ?

 

[NeuseRvrRat]

with the primer pocket uniformer i use, you just go until the tool bottoms out. this means the case head will square up against the tool.

 

[gregj]

I found the Possom Hollow tool, looks like it does as you mentioned. I will be ordering one soon.

 

[NeuseRvrRat]

i use sinclair's version. it also makes a very good primer pocket cleaner. much better than the brushes and the scraper type.

 

[mtnlvr]

So when the shoulder of the unimormer bottoms on the case, how do you prevent marring of the case head around the primer pocket?

 

[Dthunter]

What you see (I believe) is that your uniformer cut squarely to the depth of its setting.
The dull colored brass that is angled is just a primer pocket that was swedged wayyy too deep and poorly.

Not to worry though, normally on a subsequent firing, the deeper portion of the primer pocket may flow out towads the bottom of the case enough for your uniform tool to be able to clean it up.

Trust me, if the uniformer tool only cleaned a small part of the pocket like that, you can only improve it from there.

Have fun shooting!

 

[MtnCreek]

I get a little circular marring on the head. Just stop when it bottoms out and it will not be very noticeable. The little tool I use (Lyman or RCBS) fits pretty snug and by the time it’s in the pocket deep enough to start cutting, it’s aligned square.

 

[NeuseRvrRat]

So when the shoulder of the unimormer bottoms on the case, how do you prevent marring of the case head around the primer pocket?

it'll put a ring on the case head if you go too long. not a big deal to me.

 

[W.E.G.]

Is the ammo loaded with "uniformed" primer pockets more accurate or reliable for your intended purpose?

 

[NeuseRvrRat]

nope

 

[USSR]

i use sinclair's version. it also makes a very good primer pocket cleaner. much better than the brushes and the scraper type.

+1. In addition to using it for precision ammo, I use it on all my .30-06 brass designated for use in my Garands, to ensure no high primers.

Don

 

[gregj]

Thanks for the info guys. Last weekend I picked up one of these. Unscrewed the uniform and chucked it into my benchtop drill press. Works quite nicely, and the primers seem to seat much better now.

 

[MtnCreek]

and the primers seem to seat much better now.

A lot of the standard brass I’ve used seems to have more of a radius at the bottom of the pocket, not a strait cut. After uniforming, the primers set with a better feel.