Problem With DePriming With a Dillon 750

[cxm]

 I had a really frustrating time yesterday... I was trying to set up the tool head with 9x19 dies.  

 

All went fairly well until I ran some test cases through the 750.  About 20% of the once fired Mag-Tech cases did not deprime correctly.  The primer would be bent outward and extend more or less half out of the primer pocket... but the primer did not eject.  This is extremely frustrating to say the least.

 

I was using a RCBS size/deprime die that worked great in my old Dillon 550b. 

 

Anyway, I don't have a Dillon 9mm carbide die so I decided to use my 38Super die which is labeled as being good for both 38Super and 9mm.  Previously I had called Dillon and  they didn't have much help to offer other than to put to deprime pin in a drill and re-shape the pin into a truncated cone shape... which I did with no improvement.  Unfortunately I got in improvement with the Dillon dies... maybe even worse.  I also have a Lyman size/deprime die so I gave that a whirl too... no improvement. Of course this happens on a Friday so Dillon is closed today...

 

I have looked on the net for help on this topic but with not much luck.  There is some speculation this is caused by a  vacuum created in the die sucking the spent primer back into the primer pocket. 

 

Has anyone else had this issue?  And if so would you please share your solution?  I have been thinking and wonder if drilling a small hole in the die body might releive the vacuum and solve the problem?  Or would I just ruin the die?

 

Any help would be appreciated.

 

Thanks in advance

 

Chuck

[RangerTrace]

I'm having this about once every 500 rounds on my 1050 with Lee decapping/sizing die.  I think it's just crimped primers.  I can't even feel that its happened until I smash another primer on top of the one that didn't come out.

[BoyGlock]

In my 550 I filed a bit of the depriming needle tip on one side only to create an eccentric force and push the spent primer a bit to the side to prevent it from sticking on the needle tip and be drawn back to the primer hole. I got this trick from this forum I think. 

[ysrracer]

Crimped primers? Popped de priming pin? Norma cases?

[Farmer]

Crimped primers need more recapping pin length. The primer stretches before clearing the pocket and if you don’t have enough pin length to push it clear it just stays there. Try lengthening your decapper or maybe pre-process them on your 550. 

[IVC]

If it's not punctured (ringer), you need a longer pin. The longer pin will either force the primer out (yay) or puncture it and cause the ringer (boo). If you now get ringers, you'll have to change the pin into something wider, which usually means you'll have to experiment with different dies. 

[shred]

The other thing that happens is crimped-in primers fold-in on the decapping pin and get stuck to it and when you retract, they get pulled back into the pocket.  Polishing the pin and having it at a slight angle (just don't make it perfect after it bends a little) helps keep that from happening.

 

Vacuum is not it, or you'd hear a pop whenever you deprimed a round, plus even were there a perfect vacuum in the case, there'd only be about 5 oz of force pushing the primer back in.

 

 

 

 

[Nc1911]

Use a Mighty Armory universal decamping die and do a 2 step process and decap separately before loading.

[Squirrel45]

I also get this, most of the time it's European crimped 9s that cause issues. However I have found that other non crimped brass will also cause this. Unfortunately I don't have a Dillon decapping die. On the one year wait list. 

[sharko]

Probably primer pullback. Several years ago I had a rash of that with Speer brass on my 650 with the old style (not spring loaded) sizing die.

Dillon told me to file/grind the pin flat on the bottom and it seemed to greatly help. Since I have the newer dies and may only have that once in 10K.

[4n2t0]

Crimped primers (I don't use Mag-Tech cases, so I wouldn't know) or .......

 

 

If it is primer "suck back" reshaping the extraction pin, as suggested by other members, usually does the trick. Also, if you can afford to do so, I would discard the Mag-Tech cases altogether.

Edited July 30, 2023 by 4n2t0

[m700]

Like Shred mentioned I think its primer pull back.  You can try replacing the pin, polishing the pin or lowering the die if possible. you may be able to find pins that are a bit longer or thinner

[DeepFried]

Lots of good info in here. If you do have a primer, pullback issue, this image shows how I modified a Dillon pin to prevent that.

 

Consistently had issues with blazer primers not getting removed until making this modification.

[JonasAberg]

I've had the same issue with magtech brass, using a Dillon decapping die.

I just got fed up with it and started sorting out the magtech cases.

[APL-G35]

As above either extend the decap pin or you are getting primer pull back.  I Chucked my decap pin in a drill, sanded with 1200 grit and then scotch brite to polish,  after I did this no more issues.