I'm starting to question the use of ppu's for brass prep. As I look at the debates on wet verses dry, rice verses ss, one of the things that I have noticed is the scratching that a ppu can do to the side walls of primer pockets. It may be the reason that my primer seating can be rough at times. Any ideas?
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Are primer pocket uniformers good or bad?
- Thread starter Sgtsideways
- Start date
FWIW - I see no evidence that cleaning primer pockets does anything. Uniforming may be valuable with lower quality brass, but I still haven't seen any evidence that it does anything. Scratches and variance in seating pressure shouldn't affect anything as long as primers are consistently seated to the correct depth. I'm really enjoying the micro adjustable priming tool "Frankford Arsenal Platinum Series Perfect Seat Hand Primer Seating Tool". This was the best primer related upgrade I've purchased.
An individual would really need to test it out side by side with and without to see if there is a tangible difference. My biggest variable for now is probably the accuracy of my mechanical scale. I am waiting on an Auto Trickler to reduce the scale variance, speed will be a bonus.
For myself, I do use the Sinclair PPU to remove another potential variable in the brass. It is an extra step, I also use a K&M flash hole uniformer, another extra step.
For my own "feels" is probably the best reason why I do it, thinking if I remove as many variables as possible that I can control, it may improve the performance of my handloads.
It's not always enjoyable, especially sitting down and doing 200+ cases. Case trimming on a Wilson is probably the worst part of my case prep. A drill press with the PPU in it is the easiest part.
I put the effort into case prep on once fired brass so I know they are as uniform as possible, short of weight sorting.
I haven't spent the money on Lapua or other premium brass, I shoot mostly Hornady or FGMM factory and then reuse the cases for my purposes. Factory Match ammo is usually my baseline for performance in both checking out a rifle as well as eeking out a better group on the reloading bench.
For myself, I do use the Sinclair PPU to remove another potential variable in the brass. It is an extra step, I also use a K&M flash hole uniformer, another extra step.
For my own "feels" is probably the best reason why I do it, thinking if I remove as many variables as possible that I can control, it may improve the performance of my handloads.
It's not always enjoyable, especially sitting down and doing 200+ cases. Case trimming on a Wilson is probably the worst part of my case prep. A drill press with the PPU in it is the easiest part.
I put the effort into case prep on once fired brass so I know they are as uniform as possible, short of weight sorting.
I haven't spent the money on Lapua or other premium brass, I shoot mostly Hornady or FGMM factory and then reuse the cases for my purposes. Factory Match ammo is usually my baseline for performance in both checking out a rifle as well as eeking out a better group on the reloading bench.
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Ive never done it, if the manufactures dont do it from the factory why would i? Just seems like an extra thing to sell me. I do clean primer pockets, but dont uniform them.
Pretty much anything over 50 pieces sucks, but the Wilson is precise.
You would be surprised at how much variance thier is. I consider it like blueprinting heads after all it's where the spark plug goes.
But would you consider it using clocking washers on the spark plugs? Lol, ive been looking at one but its actually heads that give me pause. When you polish the ports on a head you remove the tiny bumps that cause air and fuel to mix, forever people polished and tuned for the wasted gas... im always interested in data on the primer pocket uniformer, but im not sure if im sold.
When you open up a hole a flame is forced thru the flame gets cooler... at least in my experience.
The pocket uniformer just sets depth consistently. The K&M tool makes it .08 consistantly and deburrs the punched flash hole that potentially interrupts the flame.
I am not saying that it makes a difference because I cannot prove that definitively. I only do it because it adds consistancy to what I can control, or ar least to the level I am willing too.
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So... excuse my ignorance, but its a 2 tool process. Or i can do either or? I may have to invest in the uniformer then, i thought it did both the hole and depth.. thank you for that explanation sir.
For me its 2 tools. The Sinclair primer pocket uniformer is the one I use. Its solid carbide and non adjustable so it cuts like butter and never gets outta wack. The K&M tool is also fixed. Both I think are the best designs. I have tried other brands but those 2 are the best I've found.
I figure if Imma do the pocket the hole should get the same attention. I was surprised at the amount of brass removed by the pocket cutter, but it is designed according to Sinclair to cut to "spec" for depth. The K&M definitely removes a burr. I have read that Lapua drills and reams thier flash holes, most others punch them. Cue those off center holes that Winchester is almost infamous for.
I figure if Imma do the pocket the hole should get the same attention. I was surprised at the amount of brass removed by the pocket cutter, but it is designed according to Sinclair to cut to "spec" for depth. The K&M definitely removes a burr. I have read that Lapua drills and reams thier flash holes, most others punch them. Cue those off center holes that Winchester is almost infamous for.
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What is the chance of oversizing an off center winchester hole? I bought 140 rds of new winchester brass for 338lm awhile back i havent touched yet....
Stop cutting with the tool when you feel it stop removing burrs.
If you start with properly trimmed cases, you can use a deburring tool that uses a cutter stop on the mouth of the case. Prevents over-cutting.
My deburring tool lives on my case prep center and the brass gets deburred as part of its first trim, debur and chamfer.
@Sgtsideways
PP uniforming is easy for most brass. If yours is getting nicked along the edges, you're not holding the case straight on the cutter.
One of the things I do is to let it do a partial cut, lift the case, brush the chips and continue cutting.
If I feel it grabbing, I lift and brush again.
K&M Professional Flash Hole Uniformer Standard 0.080
Hand Loader! Are you looking for improved accuracy? Accuracy demands consistency and precision in every operation and component used in hand loading....
www.midwayusa.com
I was in correctly calling it K&N its K&M for the flash hole uniformer. It has a stop on the cutting end to verses one on the shank so you can't go to far like the Lyman and some other brands. The K&M has a sliding brass taper to center in the case mouth.
On a .338LM is a large enough case in length and case mouth I would think there is enough play with the K&M to not cut oversize.
SINCLAIR INTERNATIONAL CARBIDE PRIMER POCKET UNIFORMERS | Brownells
The Sinclair primer pocket uniformers are precision ground from one solid piece of tungsten carbide, so there is no need to worry ...
www.sinclairintl.com
The Sinclair pocket uniformers.
Primer pocket depth consistency supposedly also has an effect on firing pin strike and therefore ignition. I think @orkan has touched on this with the Primal Rights CPS (Competition Primer Seater). IIRC he doesn't think uniforming is necessary with the CPS. I use both and seat to the bottom of the pocket for now. The primer anvil should be as consistently in contact and seated in the priming compound as I can get it.
Primer seating depth has an affect on accuracy, and brass grows in every direction.
If you shoot and shoot, and shoot without uniforming your pockets to the same depth every time, you’re never seating your primers to the same depth every time, or getting the same crush.
Don’t cut the diameter, just the bottom.
If you shoot and shoot, and shoot without uniforming your pockets to the same depth every time, you’re never seating your primers to the same depth every time, or getting the same crush.
Don’t cut the diameter, just the bottom.
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Primer pocket uniforming dates back to the NRA Highpower days where shooters would single load a round and drop the bolt on M1 Garands and M14/M1A's. A high primer on a handloaded cartridge would induce a slam-fire with potentially disastrous results.
I've been doing both for a long time. Truthfully I can't tell the difference between doing it and not doing it. And I have a few pretty accurate rifles. But it makes me feel good. I use a K&M tool for the flash hole and a non adjustable Sinclair tool for the primer pocket. I use a reamer that fits in my Wilson trimmer if there is a primer crimp.
I also use the Sinclair tool to remove carbon from the primer pocket and it usually gets a little brass along with the carbon. So the brass does expand a little in that direction. The same goes for neck turning. I can cut a little brass from the neck after a few firings.
I use a cordless drill to power these tools and work over a plastic tub. Its amazing just how much brass shavings come from these operations.
I also use the Sinclair tool to remove carbon from the primer pocket and it usually gets a little brass along with the carbon. So the brass does expand a little in that direction. The same goes for neck turning. I can cut a little brass from the neck after a few firings.
I use a cordless drill to power these tools and work over a plastic tub. Its amazing just how much brass shavings come from these operations.
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