Large pistol primers in 308 reloads
- Thread starter steelgray
- Start date
.30/06 FTW
CGN Ultra frequent flyer
- Location
- Thunder Bay, Ontario
Oh boy here we go. Why don’t you make some and find out?
I don’t believe you...if you don’t have issues is because you shoot and reload from your keyboard…
Some of us shared our experience gained from actual, personal experimentation. Yours sounds like BS.
Just out of curiosity, I looked up the .500S&W. Peak pressure is listed at 60,000psi. Originally loaded with LP primers, now LR.
Magnum pistol cartridges operate at rifle pressure levels. It follows that the LP magnum primer would have to be able to handle rifle pressures. Regular LP primers, not so much. Non-magnum pistol cartridges operate at less than half the pressure of the magnums.
So, from the pressure standpoint, LPM primers should work in rifle cartridges.
Now, the large pistol primer is shorter than the LR. So, if it is fully seated, it will be recessed further into the pocket. When it fires, it is going to be forced back until stopped by the bolt face. Probably going to be well flattened in the process; maybe pierced. If seated flush with the base of the case, it is going to move forward when impacted by the firing pin. This isn't going to help ignition.
Mention has been made of bolt faces gas cut by blown primers. Exactly what I would expect if non-magnum primer are used in full load rifle cartridges.
The OP has speculated about the risk of slamfires if pistol primers are used. I expect that the risk of slamfires would be greatly increased, the standard LP primers having a thinner, softer cup. Easier to ignite by design.
If the OP really wants to know if LP primers can be used in full .308 loads, he should conduct some experiments. Remote firing with a long string might be a good idea, along with using a rifle that he is prepared to write off if damaged
He could then report back with his observations.
Magnum pistol cartridges operate at rifle pressure levels. It follows that the LP magnum primer would have to be able to handle rifle pressures. Regular LP primers, not so much. Non-magnum pistol cartridges operate at less than half the pressure of the magnums.
So, from the pressure standpoint, LPM primers should work in rifle cartridges.
Now, the large pistol primer is shorter than the LR. So, if it is fully seated, it will be recessed further into the pocket. When it fires, it is going to be forced back until stopped by the bolt face. Probably going to be well flattened in the process; maybe pierced. If seated flush with the base of the case, it is going to move forward when impacted by the firing pin. This isn't going to help ignition.
Mention has been made of bolt faces gas cut by blown primers. Exactly what I would expect if non-magnum primer are used in full load rifle cartridges.
The OP has speculated about the risk of slamfires if pistol primers are used. I expect that the risk of slamfires would be greatly increased, the standard LP primers having a thinner, softer cup. Easier to ignite by design.
If the OP really wants to know if LP primers can be used in full .308 loads, he should conduct some experiments. Remote firing with a long string might be a good idea, along with using a rifle that he is prepared to write off if damaged
He could then report back with his observations.
^good points in there, keep in mind the .500 S&W is no longer using a LP primer, and when it did it wasn't for long. Funnily enough it was due to problems with pierced primers. I believe it really only the .460/.500 running true rifle pressures with large pockets. I was unfortunate enough to have a primer pretty much completely fail in a new SW revolver and the work needed to replace the firing pin bushing is very annoying, and good luck finding a replacement.
Every single LR primer out there is not only .027" thick they are very hard compared to LP, which as far as I know are all .025" thick with varying hardness. Some are really quite soft in my experience. Even if the cup is strong enough it will still be able to move a significant amount. That alone can lead to piercing.
Every single LR primer out there is not only .027" thick they are very hard compared to LP, which as far as I know are all .025" thick with varying hardness. Some are really quite soft in my experience. Even if the cup is strong enough it will still be able to move a significant amount. That alone can lead to piercing.
No one should do what I do, but for pistol powders in rifles (Trailboss, Unique, etc) I use Winchester Large Pistol Magnum primers in 7.62x54R (Mosin), 303 British (Lee Enfield), and 8mm Mauser (Turkish & Spanish mausers). I fully understand that if something were to happen to my bolt, firing pin, etc, it is my fault. But for using cast bullets or Berry's 123gr plated bullets and pistol powder, I'd rather shoot with LPM primers than use my low supply of Large Rifle primers.
YMMV
YMMV
This makes lots of sense when we are talking about lower pressure ammo. Not so much in full power rounds.
Yeah, not what the OP is asking about. Neither are black powder rifle cartridges, what a stupid attempt at being picky with semantics. The pressure isn't the only factor either. I have pierced several LP primers fireforming different cases. With the pressures I was working at I figured it must be the primer moving around or the hammer/firing pin being too much, maybe both.
Last edited:
I see that there are 10mm auto loads at about 38,000 while top loads of 7.62x39 loads seem to max out at about 44,700 cup and most loads are under 40,000 psi. I'm guessing that, in a pinch, you could use LRPs in 7.62x39 without much drama. It wouldn't be my first choice.
One thing that you'd want to look out for is damage to the bolt face. I'm mostly a low pressure single shot rifle guy, but I can say that I've seen a lot of talk of damaged breech faces caused by large pistol primers slamming into them due to them being shorter. With that said, I use them often in black power ammunition or with smokeless and cast bullets.
Chris.
Chris.
I wouldn’t hesitate to give them a try. And if they weren’t snug, I’d put a dab of blue thread locker on them after they were seated. My first test would be to try to get them to slam fire. If I succeeded, that would be the end of that experiment. Otherwise I would continue using them.
Do you need a 60,000 psi load or can a 45,000 psi load get the job done?
Load only to what is need to do the job at hand, till a better supply comes to hand.
Yes I do load LP into double number rounds, but only for paper punching with lead bullets.
Load only to what is need to do the job at hand, till a better supply comes to hand.
Yes I do load LP into double number rounds, but only for paper punching with lead bullets.
Honestly, I'm quite happy to draw on the experience of others. I don't have a lot of time or interest in reinventing the wheel. That's why I asked. There are always lots of good people out there who know more about these things than I do.
.30/06 FTW
CGN Ultra frequent flyer
- Location
- Thunder Bay, Ontario
So does this mean you aren’t going to start primer production in Canada?
I case you hadn't notice, there is always some guy - usually that one guy - who tries to make any post about me. It isn't.
Pretty sad.
Maybe that guy should get a better hobby than than surfing CGN, trying to insult people. Otherwise, maybe the mods should check-out that person's posting pattern and act accordingly.
Don't feel bad about being cautious. I don't feel bad if you don't want to take my advice on the "magnum large pistol'' primers at all.
When I first started handloading, many people felt it was the Devil's work. When more information became available and more companies started to produce components things changed.
Some people just aren't comfortable if they can't see it in writing or pictures.
Back in the day, we had to do a lot of experimenting, simply because components were always hard to accumulate and in relation to our wages at the time, almost as expensive as they are now.
Just keep in mind that this isn't alchemy or rocket science.
When using components that you aren't familiar with, start at the bottom end, no shame there. If those primers won't stand up, you will see it as you work up the loads.
I wouldn't have suggested you use the "Large Magnum Pistol Primers'' if I hadn't used them extensively before.
I had just helped a fellow with a 30-06 work up a load for his Rem 700, using H4831, Large Magnum Pistol Primers and 165 grain Hornady Interlock bullets in (horrors) FEDERAL cases, which I'm fine with.
We settled on 60.0 grains of H4831, which gave him good accuracy from his reports, and around 2700fps.
He would have liked something hotter but prudence and caution kicked in and H4831 is the only powder he has on hand in shootable quantities.
.30/06 FTW
CGN Ultra frequent flyer
- Location
- Thunder Bay, Ontario
Right, it's not about you, you only started the thread because you didn't want to use up your LRP and wanted to use LPP instead.
And came up with crazy ideas for making primers in the other thread and wouldn't listen to people when they told you they were bad ideas. Just pointing out how you contradicted yourself.
I don't mind that people aren't knowledgeable because we all started some place. But some people are so unknowing they don't even have the experience to grasp how much they don't know and some of those people tend to be very aggressively outspoken on subjects where their personal knowledge is zero and everything they know is gleaned from internet surfing. That thread about factory brass being intentionally made so it couldn't be reloaded was a perfect example. That thread was full of silliness and couldn't be taken seriously by most, but the unfortunate possibility is that another unknowing newb will read it and be lead astray like you were.
