Failure to deprime

[jrplourde]

Of all my dies from RCBS, only one has the trait of not depriming on the first try. Totally impractical with my new Dillon. It's as though the spent primer is logged on the end of the pin and gets drawn back partially into the primer pocket. Needs a second try and often with the usual "popping" sound.

Anyone have any thoughts re this strangeness?

Bob

 

[max]

I don' think this is uncommon. Just adjust the decapping pin so that it sticks down a bit further.

 

[jrplourde]

I don' think this is uncommon. Just adjust the decapping pin so that it sticks down a bit further.

I've done that but maybe not enough. Will try this afternoon and shine a light under the shell holder and see what's happening. Should have done that some time ago come to think of it.

Bob

 

[H Richard]

Decap pin needs to extend 3/16 to 1/4" below base of die. Some shell holder's are a little thicker, and you may need just a bit more.

 

[Jim Watson]

I have been having "primer pullback" with my current batch of mailorder once fired 9mm P.
I think I corrected it today.
I put a slight taper on the decapping pin, about 3/16" back. SLIGHT taper, not a point.
The best way would have been to chuck the pin in a drill and turn it with a fine file, stone, or sandpaper, but my cordless drill expired and my corded is not to be found. So I did it with an unlicensed Dremel. It isn't pretty but I just loaded 100 rounds without a pullback where before I was lucky to go 20.

 

[MrPhil]

To add to Jim's suggestion, give the pin a close visual inspection. Maybe a rough spot needs polishing.

 

[Hoptob]

I have been having "primer pullback" with my current batch of mailorder once fired 9mm P.
I think I corrected it today.
I put a slight taper on the decapping pin, about 3/16" back. SLIGHT taper, not a point.
The best way would have been to chuck the pin in a drill and turn it with a fine file, stone, or sandpaper, but my cordless drill expired and my corded is not to be found. So I did it with an unlicensed Dremel. It isn't pretty but I just loaded 100 rounds without a pullback where before I was lucky to go 20.

I tried this trick before on RCBS die. It helped to reduce pullbacks but didn't cure it entirely. Seems like for any shape of the tip, there would always be a few stubborn primers that fit it perfectly and get stuck on it. They would get pulled back and re-seated in the next station. I went with Dillon depriming die - they have special spring assembly built into the die; it shakes primers off the pin. With Dillon die I did not have re-priming problem.

Mike

 

[Jim Watson]

The die I tapered the decapping pin on IS a Dillon. The spring was not flipping them off the tip once the anvil was gripping it firmly.

 

[jrplourde]

The die I tapered the decapping pin on IS a Dillon. The spring was not flipping them off the tip once the anvil was gripping it firmly.

Yes, it's pullback but Jim, what spring. These by the way are .357 cases. No others are a problem. Just measured: there is only .003 difference twix the 9mm (no problem) and the .357.

Bob

 

[flash60601]

Have you tried, just barely BLUNTING the point of the decapping pin with a fine stone?

I have an RCBS, Lyman and Lee set in 9mm, and I found different profiles of pin points in the replacement pins and when I blunted them a bit, still maintaining a slight radius , I practically ended pullback in either die.

Flash

 

[Hoptob]

The die I tapered the decapping pin on IS a Dillon. The spring was not flipping them off the tip once the anvil was gripping it firmly.

I see your point, Jim. Perhaps you just had a rough pin; hope taper fixed your problem. I found Dillon decapping die to be very reliable with all sorts of brass.

Mike