Dillon 550 Shallow Priming

[Airw4ves]

Hey all, looking for some insite into a problem Im having with my Dillon 550C. Im depriming and priming as a single step on my press, but find it primes too shallow. Im only .001 below flush on average, and would like it to be .003-.004
Im using once fired Lapua brass and used a primer pocket uniformer just to be sure (none required any trimming), but no change in depth found.

If no method is doable I am looking at purchasing a 21Century hand primer, but if I can get consistent results from my Dillon, I’ll gladly put that $ to better use. Im not looking for benchrest accuracy here, but I do like consistent results from my ammo.

 

[Threadcutter308]

Hey all, looking for some insite into a problem Im having with my Dillon 550C. Im depriming and priming as a single step on my press, but find it primes too shallow. Im only .001 below flush on average, and would like it to be .003-.004
Im using once fired Lapua brass and used a primer pocket uniformer just to be sure (none required any trimming), but no change in depth found.

If no method is doable I am looking at purchasing a 21Century hand primer, but if I can get consistent results from my Dillon, I’ll gladly put that $ to better use. Im not looking for benchrest accuracy here, but I do like consistent results from my ammo.

Not sure why your 550 doesn't appear to be seating deep enough. I have a 650, but no 550, so I can't offer intelligent comentary there. I do have a 21C priming tool. It is expensive, but it is the first tool of all my re-loading gear that I can say that I would not want to be without. Buy it, unbox it, run it and have someone video the grin on your face the first time you use it.

 

[spife7980]

Can you measure them? Measure the depth of the primer cup in between the anvils, measure the depth including the anvil, subtract those to see how much crush of seating the anvil is and then take the depth measurement of your calipers to see how deep the pocket is in the case.

 

[NighthawkCG]

Have a 550 as well that i have used for years and had some similar problems. Was using .223 brass.
1) Noticed it was some of the primer pockets in the brass. I was using LC brass. Got a brass station to uniform pockets, got a bit better, but not much.
2) Noticed the little cup on the press that holds the primer is a limiting factor for depth of the primer (it bottoms out). Disassembled, made a few passes of the bottom of the cup on a file and took a few thousandths off the bottom. Got even better results. Only took 1-2 thou off cup. This was also in an article for accurizing the 550.
3) Switched brass with a difference thickness rim and primer depth changed... This is the interaction between the priming mechanism and the plate that holds the brass down. New brass wasn't bad, but also wasn't the same depth as before.
4) Bought the Frankford Arsenal hand primer. Can adjust depth easily. Love it - consistent and can do it while watching TV or whatever. Won't prime on 550 any more unless I'm doing bulk loading.

I still use the prep center to do all my new brass. Not sure if its totally necessary, but it ensures there aren't any burrs or anything else messing with SDs.

 

[Sheldon N]

Read article here... answer is on pages 3 through 6.

https://www.dropbox.com/s/mmk8tv8yrk7vii7/12.23.15-Dillon-Prometheus-Article.pdf?dl=0

 

[memilanuk]

While @Sheldon N probably hit the nail on the head, I'd highly recommend looking at what @spife7980 suggested as well.

I have no issues priming on my 550... but I ran into some problems trying to re-load some Prime (Norma) brass. I couldn't get the primers to seat below flush for the life of me - and I was putting way more force into than I'd normally recommend. Same thing with my hand priming tools.

Did some measuring, and it turned out those primer pockets are both a little tight, and a lot shallow - specifically in the corners. Running a primer pocket uniformer into each and every case to square out the corners kind of sucks, but it did 'fix' the problem.

 

[Airw4ves]

Thanks for the link! I’ll give it a shot this weekend