PP uniforming?

[DenisA]

Given that Fclass brass is most Likely to fail in loose PP these days, and therefore uniforming PP is removing brass from a 'critical' area in that respect, do the advantages of uniforming PP outweigh the disadvantages?

What's the best tool and why?

[Wal86]

I cant see any disadvantages in uniforming primer pockets at all.
Brass that goes (tight/primer pockets failing) happens due to not fireforming brass correctly. Your first firing is critical to brass longevity.

Cheers
Alan

[John23]

G'day Alan

Can you expand on this theory please?
I have always believed case life slowly reduces due to a combination of work hardening and heat .

How can inital fire forming effect the cases lifee ?
And what is your method of fireforming?



@ DenisA.

I use the Lyman tool that only cuts primer depth.
I don't believe this has a effect on how long the case can hold onto the primer .

[DenisA]

Fire form with light loads to work harden the base and head before you subject the case to hot loads.

I use the K&M tool john which also only does depth, but I notice the sides of the pocket at the bottom have been shaved by the side of the cutting teeth.

[Wal86]

If you over stretch the webbing of a case it weakens considerably. This has an effect on both the webbing of the case and primer pocket area. Hence tight brass and primer pocket failure

How many cases do you have that have a flat spot or a high spot (only marginal) on one side of the case about 3mm up from case head... brass moves and it has to come from somewhere.

Also uniforming PP after fireforming helps reduce the amount of material you take from the pocket, otherwise your uniforming a case thats not uniform, then fireforming the case, then when you clean out the pocket again it takes more brass away because you have just squared it up..

Cheers

Alan

[johnk]

I use the K&M tool john which also only does depth, but I notice the sides of the pocket at the bottom have been shaved by the side of the cutting teeth.

Isn't that because the tool is square & the pocket was punched with a radius, in which case, is it an issue?

[DenisA]

I use the K&M tool john which also only does depth, but I notice the sides of the pocket at the bottom have been shaved by the side of the cutting teeth.

Isn't that because the tool is square & the pocket was punched with a radius, in which case, is it an issue?

I hope so. That's what I've always thought, but last night while I was uniforming PP's, I was wondering whether it could be some minuscule movement between the tool and the PP allowing some yaw and the teeth to take too much????

[Wal86]

That little bit of movement you get is because the brass is new and not uniform.. once you fireform the case it squares itself against the bolt face, allowing your PP uniformer to then be working on a flat surface.

Cheers

Alan

[DenisA]

These cases are 5 x fired Alan. I'm a bit late this time around, but I like to go through a couple of firings before I anneal, neck turn and PP uniform. First load was a light one.

These PP are still very tight when priming. Well they were last loading, I'm keen to see how they feel after this.

[Jase PTRC]

I use the K&M tool john which also only does depth, but I notice the sides of the pocket at the bottom have been shaved by the side of the cutting teeth.

Isn't that because the tool is square & the pocket was punched with a radius, in which case, is it an issue?

I hope so. That's what I've always thought, but last night while I was uniforming PP's, I was wondering whether it could be some minuscule movement between the tool and the PP allowing some yaw and the teeth to take too much????

Dennis i use my primer pocket uniformer each time i reload to clean the primer pockets. I found the same thing as you on some cases it cuts more off one "side" if you can call it that in a circle opening on some cases more than others. when i first got the cases it didnt even cut on most of them at all. Up to my fifth firing now and still only get a minor cut in the very corners of the pocket in some cases, they dont seem to be moving much at all. Im shooting a 308 with small primer Palma Brass.

[Wal86]

Incorrect fireforming causes all these problems with brass.. If you dont fireform correctly you will stretch the webbing causing a high spot/flat spot on your case about 3mm up the body from the head of the case.... This then causes problems with sizing as when you use your body die it works harder on one side of your case than the other (which is the side you have stretched), this then effects your primer pocket and you then shave more brass off one side when cleaning out residue.. This will be the same side your body die/FL die has worked harder on. Once webbing is stretched to this point there is no coming back, your brass is on the down hill...

Light loads are only part of fireforming brass..
New brass can be greater than .005 less than chamber specs at the webbing... so what do you think happens when you touch the trigger the first time, even if you have your bullet jammed in the lands the case is laying down in the bottom of your chamber.. case blows forward, then back against bolt face and leaves you with a little high spot on one side and a flat spot on the other side of your case.. You now have an non concentric case that has been stretched in the webbing up too .0035" you cant get this measurement back as the brass will always expand greater on that side each firing after bumping causing tight cases/primer pocket failures...

Cheers

Alan

[DenisA]

I'm not cutting more off one side when uniforming PP's. It's just a shaving all around the bottom of the PP walls.

Alan, what's your solution to what you've described?

[Brad Y]

Denis

Just make your primers suit you primer pockets. Pour some water on the primers then lightly rub with wet and dry and your good to go when the correct thickness has been achieved. Remember the second and third time you use the primers you don't need to do this.

[Brad Y]

[ajvanwyk]

Denis

Just make your primers suit you primer pockets. Pour some water on the primers then lightly rub with wet and dry and your good to go when the correct thickness has been achieved. Remember the second and third time you use the primers you don't need to do this.

Is this the recipe our loved webmaster used last year at the nationals ? or was that the Boil water for tea, insert primer and pour leaves into case.... soak for 10min and seat projectile.... move to range and fire