Large Rifle Primer Alternative?
- Thread starter Handyguy
- Start date
I've read that since pistol primer cups are thinner that they can be pierced and blow out with use in a rifle. Never tried it myself though
I've switched to using my LR Magnum primers in standard rifle loads (adjusting the reloads as required) since I have 1100 of those and no magnum cartridges
I've switched to using my LR Magnum primers in standard rifle loads (adjusting the reloads as required) since I have 1100 of those and no magnum cartridges
Large rifle primers are taller as well as being much thicker and harder than Large Pistol.
Were you expecting any? You used the correct primer. Using the too tall Large Rifle primers could lead to a chain fire in your magazine with a tube fed gun.
Some manufacturer's brass will accept Large Rifle in place of a Large Pistol primer while remaining flush. You will need a very strong firing pin/striker spring to initiate them. Using a Large Pistol primer in place of a Large Rifle is stupid and will cause problems ranging from bad to immediately damaging.
Were you expecting any? You used the correct primer. Using the too tall Large Rifle primers could lead to a chain fire in your magazine with a tube fed gun.
Some manufacturer's brass will accept Large Rifle in place of a Large Pistol primer while remaining flush. You will need a very strong firing pin/striker spring to initiate them. Using a Large Pistol primer in place of a Large Rifle is stupid and will cause problems ranging from bad to immediately damaging.
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Depends what caliber your loading. Pistol calibers in a rifle your perfectly fine. If your using them for rifle cartridges your looking for trouble.
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- Saskatchewan
Pistol primers are quite different than rifle primers. Thinner metal cup so the relatively light hammer / striker impact from a pistol or revolver will still reliably ignite them. Made to handle lower pressures. The lower charge of primer compound is of lesser concern, but may not ignite slow burning rifle powders reliably. Large Rifle and Large Pistol primers differ in cup height ( primer pocket depth) too. Rifle primers are taller and fit a deeper primer pocket in the case.
Don't "try it" by substituting a large pistol primer in a rifle case for a full power rifle load because the rifle can produce pressures more than twice what a typical pistol cartridge produces. Even comparing 36,000 PSI for .44 magnum (one of the highest pressure pistol cartridges), vs 65,000 PSI for an ordinary .270 Win. shows quite a big difference.
Put a large pistol primer in a .270 standard load, and you're very likely to experience a pierced primer. Thinner primer cup and shorter so it's likely to be deep set in the rifle case, so it may back out a bit on firing and make the divot from impact of the firing pin seem "deeper" and so will blow a hole in the primer cup by cutting around the firing pin indentation. Bits of primer and powder gasses in your eyeballs could ruin your day. With a mild trail boss load or cast bullet load at mild pistol pressures, you may get away with it.
In comparison, pistol primers of the "Small" size are the same outer cup dimensions as the small rifle primers, just thinner metal cup and weaker ignition. For mild loads in rifle cartridges like the .22 Hornet, sometimes small pistol primers make an accuracy improvement and can be used safely if you know what you're doing.
Don't "try it" by substituting a large pistol primer in a rifle case for a full power rifle load because the rifle can produce pressures more than twice what a typical pistol cartridge produces. Even comparing 36,000 PSI for .44 magnum (one of the highest pressure pistol cartridges), vs 65,000 PSI for an ordinary .270 Win. shows quite a big difference.
Put a large pistol primer in a .270 standard load, and you're very likely to experience a pierced primer. Thinner primer cup and shorter so it's likely to be deep set in the rifle case, so it may back out a bit on firing and make the divot from impact of the firing pin seem "deeper" and so will blow a hole in the primer cup by cutting around the firing pin indentation. Bits of primer and powder gasses in your eyeballs could ruin your day. With a mild trail boss load or cast bullet load at mild pistol pressures, you may get away with it.
In comparison, pistol primers of the "Small" size are the same outer cup dimensions as the small rifle primers, just thinner metal cup and weaker ignition. For mild loads in rifle cartridges like the .22 Hornet, sometimes small pistol primers make an accuracy improvement and can be used safely if you know what you're doing.
LPM with cartridges with a max pressure of 45 000 psi and certain powders preferably not ball powders shouldn't be too big an issue. Personally Im not wasting any primers on x39 but thats a cartridge id try LPM on if i get some. Theres a ton of people who've subbed out LRP loads for LPM loads with certain powders. A guy on youtube does a comparison with 243. Wouldn't do full rifle loads but reduced loads on smaller cartridges shouldn't be a big issue if your in a pinch.
I have tried them in my 6.5x55. I don't load "heavy". They worked for me but that isn't saying that it will work for you. I DO NOT recommend using them and if you do ............
YOU MUST BE WILLING TO ACCEPT THE ATTENDANT RISKS
One thing I have seen is a couple of bolt faces ruined due to gas blowby around the primer. Pitted the bolt face and enlarged the firing pin hole. He kept firing knowing he was getting gas hitting him in the face. Two rifles and when asked why he kept shooting that load he said large pistol primers where more accurate. He needed new bolts. If you have a problem stop and find out what is wrong don’t keep shooting, your just going to make it worse.
I have used LP primers in the 30-30 M94 and M336 with mild loads successfully.
However, the comments here are valid. High pressures generated in many rifle
chamberings is an invitation to pierced primers and firearm damage. Dave.
However, the comments here are valid. High pressures generated in many rifle
chamberings is an invitation to pierced primers and firearm damage. Dave.
Is the 44 Mag cartridge a rifle cartridge?
https://www.sierrabullets.com/primer-substitutions/
That being said, it is safe to use a SRP in pistol applications, my 454 Casull data actually calls for a small rifle primer, in full power loads.
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Many SR primers are barely thicker than SP. Anywhere from .021" to 0.025". Federal SP (the thinnest and softest there likely is) are 0.017". One difference you can count on will be that SR are considerably harder than SP. Also worth mentiong is that there are several SR primers that are not suitable (per the manufacturer) for use above 48-50,000 PSI.
