PRIMER UNIFORMER

[Webster]

Just bought a RCBS primer pocket uniformer to try out. Never unformed primer pockets before. The primer pockets are swaged in place during the case forming extrusion process. The bottom of the primer pocket is curved. The uniformer cuts a flat bottom to the pocket. After uniforming I think I feel a distinct clearly defined bottoming out of the primer. Less guess work. An improvement.

 

[dkhunt14]

I believe it can't hurt things. It also would make the distance the primer has to fire through the same. Matt

 

[Michael C]

It may not make a difference or not but I use one every time I reload a case both small primer and large. My take is the ignition will be more uniform as the distance from the bolt face/firing pin whole is more consistent. Just be careful and don't get too aggressive as you don't want to inadvertently open up the pockets diameter. I started this as I was shooting gas guns XTC with service rifles. The whole floating firing pin thing and high primers worries.
I continued the practice when I started shooting Palma.
I use the tools that Sinclair sells chucked in a drill press at slow rpm.

 

[jlow]

The other reason apart for having uniform primer pocket depth is most factory brass (yes, this includes Lapua) is not deep enough to ensure that the top of the primer surface is slightly lower than the surface of the case head which the uniformer will get you to. It does this by squaring the bottom sides and surface. A good uniformer is made so that it cannot go past a certain depth. I use a Sinclair one which is completely made of carbide. Chuck it up in a hand drill and go to town. You only have to be care to not scratch the sides of the pocket and make sure it goes to the prescribed depth before stopping.

 

[amlevin]

Primer pocket uniformers also make nice primer pocket cleaners when loading at the range. Cleans all the way out to the edges.

 

[majohnson]

To prevent damage to the sides of the primer pockets I do it completely by hand. It not that much more time consuming. Using just a drop of oil on the sides of the tool makes it much easier and eliminates any gualing. On harder brass it might be less of a worry. However on brass like Hornady, it so easy to damage the pocket because is it softer them a lot of other manufacturers.

 

[K22]

I uniform my pocket also using the Sinclair tool which does a good job. I do mine manually because I have the time and I can control the process better.

I can clearly see the difference between uniformed pockets vs non uniformed pockets. When I remove the spent primer on a uniformed pocket there is are uniform triangular ignition marks in the pocket whereas those not uniformed show an irregular ignition marks in the pocket. Also, the uniformed pockets are much easier to clean.

However I can't say that I've ever noticed any difference in group size of uniformed vs non uniformed pockets.

 

[alb]

I use the tool made by Holland for rifle brass; it's excellent. While I'm far from good enough for it to have any effect on my groups, it sure does make primer seating very consistent.

 

[msinc]

I have the Sinclair for large pockets and the RCBS for small. I have to say that I like the feel of the Sinclair better. I don't know, it feels "sharper" to me. It seems to cut easier and faster. So easy and quick in fact that I also do it by hand. I do not enjoy using the RCBS by hand...you would think smaller equals less cutting so it should be easier. I also got priming tools that positively seat to a pre-set depth.
I have noticed better groups overall, but then I also noticed that some brass needs it worse than other. One caliber I was having trouble with needed the primer pockets cut badly. Just about every primer was high. I reloaded for years not giving it much thought. Now I believe it is pretty much a necessity. I have to wonder if the brass cases were better, more uniform quality 20-30 years ago. I shot great groups back then out of some not so fantastic rifles, with lesser loading/shooting equipment and doing less when I reloaded.
These days I am wondering if this whole reloading for accuracy thing can be overdone. Maybe I am getting older...I shot better groups with factory rifles off a former shot bag filled with sand on the truck fender than I can bench now with $1500 worth of equipment besides the rifle and scope!!!!

 

[LoganDon]

Ditto on the above. At 72 I can still shoot my bench rifle, but with the new factory hunting rifles, my ability has decreased. As I really enjoy shooting and being a range officer, I just don't think much about it. The older rifles do seem to shoot better than the new ones. I recently purchased a 1950 Model 70 in 30-06 and with a new Leupold, this thing will shoot 1/2" all day long. My older Remington 700s still shoot very well.

 

[rmist]

The K&M primer pocket tool is a great item...also carbide cutter.

 

[GrocMax]

Along with a uniformer, everyone should have the pocket go no-go gauge-

http://www.sinclairintl.com/reloadi...et-gauge-small-sku100015613-71030-150244.aspx