I made 60  762x39 cartridges from once fired brass. Took them to the range and no problems at all. The primers on these were seated ~001 to 005 depth. 

 

So now for twice fired. The same primers (Federal large rifle) in the same cases will not fully seat. They are ~001 to 006 high in the pocket. Pockets were cleaned. If I apply more force they will be crushed.

 

I made three cartridges with no powder and tested them from a mag, cycling with bolt handle. There were no slam fired primers.   

 

Any experience with this? Did the prime pocket distort or something?  This makes case trimming measurements a real mess.  These are not crimped but maybe I needed to ream the pocket anyway??

 

Thanks in advance.

 

Make sure the crimp ring is gone. Re-ream the pockets and try again.  If same result, pockets may be distorted.  Usually from cheap brass. 

If they wont seat all the way you will need to get a primer pocket uniforming tool.  High primers are dangerous.  Cycling a few manually is not a good indicator of whether or not a slam fire will happen at the range.  A high primer is believed to be the common cause of the not too common slamfire.  Why risk it?  You only get one face and one set of hands in life.

Did you notice any overpressure signs?  Where the primers you popped out totally flattened or blown out where the firing pin hit it?  Even cheap brass usually wont distort a primer pocket that bad unless it was a HOT load last time around.

Ken

Thanks guys. I found with just a little research that this is a well known problem. Another dude with the same problem was using the same brand brass, S&B. Who woulda thunk? 

 

Looks like I am buying a 'uniformer'.

The dillon swager is awesome and well worth the money if you have a lot of brass.

Im glad you found the problem.  If it is really just the brass that is a relief!  If you have any type of motorized case prep device you can usually get the RCBS uniformer to use with it from Cheyanne Mountain Outfitters.  I do think they had them in stock yesterday when I was there.  If you do not have a motorized case prep device you can purchase one of them there too.  I saw them yesterday.  You can also use the RCBS tool by hand with the threaded handle they sell for primer pocket brushes but you will have to work hard that way.  The last option is to use the RCBS uniformer with a battery drill if you have one of those handy already. 

On a side note, I find it necessary to uniform most lake city 7.62x51 brass because of the same problem you are having with the S&B brass.

Ken

Also, what Mike said above is the truth!  Awesome tool!

Ken

The dillon swager is awesome and well worth the money if you have a lot of brass.

 

RCBS is cheaper and works pretty much the exact same way but different enough to not get sued. I like it for the price, the fact it is harder to totally mess up your brass on it (dillon gives you way more leverage than you need), and that you don't need much bench dept to mount it. I have my trimmer and swaged mounted on wood which I swap out to the same spot on my bench that has two threaded posts and thumb screws to secure it. The dillon would require I clear the bench to the side or use up a lot of depth. 

NJKen --   the old primers pretty much looked perfect. I thought I had a conservative load, not hot. But maybe it was hotter than the S&B factory  load. 

 

Another general question  - as I cut brass with the uniformer from the pocket bottom, does this weaken the shell pocket and reduce the number of possible reloads?  

 

Another angle - how many uniformer passes can you reasonably/safely do?  

 

 

NJKen --   the old primers pretty much looked perfect. I thought I had a conservative load, not hot. But maybe it was hotter than the S&B factory  load. 

 

Another general question  - as I cut brass with the uniformer from the pocket bottom, does this weaken the shell pocket and reduce the number of possible reloads?  

 

Another angle - how many uniformer passes can you reasonably/safely do?  

After you set the tool to the proper depth, that's it! You don't change the setting to go deeper into the pocket. You do each case once. To clean the pocket for the next reload use the brush.

NJKen --   the old primers pretty much looked perfect. I thought I had a conservative load, not hot. But maybe it was hotter than the S&B factory  load. 

 

Another general question  - as I cut brass with the uniformer from the pocket bottom, does this weaken the shell pocket and reduce the number of possible reloads?  

 

Another angle - how many uniformer passes can you reasonably/safely do?  

If you dont overcut it there is no weakening.  I have never had to uniform a primer pocket more than once.  As stated above, just clean em with the pocket cleaning method of your choice if they get ugly.

In most all reloading manuals there is a cartridge dimension table in the section for the cartridge you are loading.  That is where you get your depth for the primer pocket.  Setting the uniformer to the rite depth is fairly straitforward.

Ken