Reply With QuoteBrownells sells a go. No go gauge for primer pockets
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Primer pockets getting loose
Have some pockets getting a bit loose ,primers are going in with a fairly light squeeze . My question is how loose is to loose and how to determine to loose?
Brownells sells a go. No go gauge for primer pockets
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Loose primer pockets are a sign of over pressure beyond the cases elastic limits and this varies with case brand and brass hardness. Example my 30-30 Winchester cases at 43,000 psi chamber pressure die of split necks. And if your primer pockets are getting loose with higher pressure cartridges its time to reduce your load or buy new brass.
Switching to a larger diameter primer can fix the problem but is not a fix for loads too hot for that brand of case.
Below just because your primers become loose doesn't mean the case is done for. Primer pockets and primers vary in diameter and a larger primer can fix the problem.
I use pin gauges .0005 smaller than the primer to check the primer pockets. And the chart above and checking the primer pocket diameter will let you know when to change primer brand.
I use the Lee depriming tool to check loose primers, if the primer moves with light finger pressure the case goes in the scrap brass bucket.
NOTE, your not hitting the primer punch or using excessive force with Gorilla finger pressure. And if the primer moves with "light" pressure the primer pocket is too loose.
Double post-dyslectic fingers
Good post Ed. Why are we getting loose primer pockets? How many firings? What is your recipe?
The Dunning-Kruger effect is alive and well.
Simple answer, don't load hot beyond the elastic limits of the brass.Originally Posted by Robinhood
The hardness of the brass in the base and the thickness of the flash hole web adds strength the the base of the cases.
Guess which case below is know for short reloading life.
And again primer pocket longevity is based on chamber pressure and if the cases are made Ford Truck Tough.
Simple Trick for Monitoring Pressure of Your Rifle Reloads
http://www.hodgdonreloading.com/reloading-education/tips-and-tricks/simple-trick-monitoring-pressure-your-rifle-reloads
One of the first rules of handloading is to always follow the approved reload data. The cautious reloader gradually works up to approved maximum loads to ensure his particular gun does not show pressure signs. Generally this is visual observation of the fired shell case head and primer. There is another slick way to check for pressure signs if you are interested.
Using a blade micrometer that measures in ten thousandths (.0001"), new, unfired cases can be gauged before and after firing to determine reasonably accurate maximum loads. Micrometers measuring in thousandths (.001") are insufficiently accurate to perform these measurements, and should not be used. Previously fired cases cannot be used accurately due to various levels of brass hardening. Measurement is taken just ahead of the extractor groove on the case head and must be taken at the same place on the case before and after firing. By placing a small mark on the case head – entering the cartridge in the chamber with mark at 12 o’clock – a consistently accurate measurement can be taken with each firing.
Lower pressure rounds, like the .30-30 Winchester, usually yield maximum pressures at .0003"-.0004" expansion. Modern cartridges, like the .223 Remington, will show maximum pressure at .0004"-.0005", while .308 Winchester, .270 Winchester, etc., typically yield .0005"-.0006" expansion at max pressure. Magnums, like the .300 Winchester Magnum, show maximums at .0006”-.0007” expansion, and should be measured on the belt.
In conjunction with these measurements, case head signs of pressure should be monitored as well. These signs include very flat primers, slightly cratered primers, ejector marks on the case head, and stiff extraction. All these case head signs indicate high pressure, and loads should be reduced until these signs disappear.
As always, start with the beginning load listed, and cautiously work up to the maximum shown for that set of components, using the methods listed herein.
So my question was an attempt to get the OP to divulge some missing information.
The Dunning-Kruger effect is alive and well.
@ biged:
do you use the Lee decapper pin on fired or unfired primers when testing??
Wow! Excellent info!
The only problem I have with the Hodgdon procedure is that blade micrometers are horrifically expensive.
Moving to the OP, ths is one of those times where our virtual instructor stomps a foot! Reiterating comments already made, loose primer pockets after a few firings tell one that the load is too hot for the brass. The overpressure is not related to action strength.
Why? The base is not supported by the chamber wall. The growth in primer pocket diameter tells us that the brass has already stared to flow and and is close to blowing out. Things might be OK with the recipe otherwise, but a warm day or any of the other multiple factors that can cause a load to have a few KSI more pressure will make it flow faster. That means the case will fail and spew and cause hot gas and warm brass partcles to places we don’t want them to visit.
This sequence is independent of absolute pressure. Rather it is chamber pressure relative to the strength of the brass one is usiing.
BOTTOM LINE: Back off the powder charge. The loss of velocity makes very little difference in drop, drift or maximum bullet expansion range.
You can use a flat harden punch and a ball bearing to tighten primers, Amazon sells no go/ go pins of any size imaginable .
Wonder which primers have slighter larger diameter properties. I know Fed Match 210 are small
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It would be nice to know small or large primer and the cartridge (chambering and brass manufacturer) and load. Though the answer would be the same.
If you are loading near max then after six or right reloads of anything you may be getting loose pockets. Some brass is softer than others (I understand Alpha Manufacturing lasts better than others). Milder loads maybe a dozen reloads, but by then there may be other reasons. If you see blackening around the primer after you shoot the time is past. This summer I was playing with a hot load and ejected a primer and the pocket was way larger than the primers. First time I got to test the gas vents on my Savage. Tight bolt and when I did get it open the primer was missing and I found it in the magazine A real eye opener! When I checked the earlier rounds of that batch I had two warning "blackenings" around the primers of fired cases. That was on Brass that had been fired and reloaded only twice prior.
I use a Lee Auto-Prime hand-primer and when they start to feel easy to my arthritic, office worker's hands it is time to retire the brass.
"They couldn't hit an elephant at this distance." Last words of Gen. Sedgwik
If the primer goes in real easily I smack the side of the case head against the bench top and try to pop the primer back out.
Even if it comes out part way the case gets chucked. I have used a hand held punch to push lots of them out without issue.
It would probably be wise to use gloves but I don't.
Everything has a price, and brass is part of the price associated with max performance loads.
After 2 firings my magnum hunting gun ammo is for practice only, I consider that cheap insurance as opposed to a case failure.
Really? How?
The Dunning-Kruger effect is alive and well.
All the ball bearing does is crimp the mouth of the primer pocket and over bevel the mouth of the primer pocket. The Lapua case below has a ejector mark from excessive pressure.
You can also see the deep bevel decreases primer support and the fired primers look like mushrooms. The photos below came from another forum where I had a running gun battle over deforming the base of the case using a hammer and a bolt.
In another forum someone made a die like a Lee bulge buster that would compress the entire base of the case and make the primer pocket diameter smaller. Meaning a much better idea than using a ball bearing and smacking the case with a hammer.
The ball bearing method reminds me of the film we saw in Jr High shop class on Primitive Pete. AKA shade tree hammer and chisel mechanics that hairy knuckles drag on the ground.
When your only tool is a hammer all jobs look like nails.
I believe that is called "Maslow's Law"
"They couldn't hit an elephant at this distance." Last words of Gen. Sedgwik
Pretty sure it's 'Maslow's theory of needs', a theory of human motivation culminating in 'self actualization'. But that's beside the point. No way would I use a crimped in primer on brass that's been used so much it needs that.
Thank you DogT
I think Stumpkiller's needs were to increase his post count and baffle us with bovine skat.
If you look at his Bio he works in a sewage treatment plant.
No one appreciates us until we close the valves and your basement fill up.
Doin my part to keep the Susquehanna River and Chesapeake Bay clean. That and the prestige of being able to say "I work at a sewage treatment plant."
Chicks dig that.
"They couldn't hit an elephant at this distance." Last words of Gen. Sedgwik
Ed, I am continuously trying to bait the uninformed yet you continue to educate. Awesome!All the ball bearing does is crimp the mouth of the primer pocket and over bevel the mouth of the primer pocket. The Lapua case below has a ejector mark from excessive pressure.
You can also see the deep bevel decreases primer support and the fired primers look like mushrooms. The photos below came from another forum where I had a running gun battle over deforming the base of the case using a hammer and a bolt.
In another forum someone made a die like a Lee bulge buster that would compress the entire base of the case and make the primer pocket diameter smaller. Meaning a much better idea than using a ball bearing and smacking the case with a hammer.
The ball bearing method reminds me of the film we saw in Jr High shop class on Primitive Pete. AKA shade tree hammer and chisel mechanics that hairy knuckles drag on the ground.
Stump, Haha. You reminded me of a tee shirt a plumber I knew used to wear. "Your $h!t Is My Bread and Butter."
The Dunning-Kruger effect is alive and well.
I was a electrician on a military base and our worse job was replacing the pump motors in the bottom of the $hit pit in the sewage plant.No one appreciates us until we close the valves and your basement fill up.
Doin my part to keep the Susquehanna River and Chesapeake Bay clean. That and the prestige of being able to say "I work at a sewage treatment plant."
Chicks dig that.
Chicks do not dig that, when I got home my wife said I smelled like $hit.
The only three things a plumber needs to know.
1. Payday is on Friday
2. $hit rolls down hill
3. Don't bite your nails.
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