Lg Pistol primers (vs Rifle) in CB loads?

[Martin Luber]

Since pressures are lower for cast bullets rifle loads, has anyone focussed on using lg pistol primers instead of lg rifle in medium volume cases? Say 30-06 and 308?

I could forsee issues ( ignition) with standard rifle powders like 4831 but not with 2400, red dot, or unique.

Thoughts?

[toallmy]

I use lg pistol primers in unique loads out of the 30-30 as well as 7x57

[RedlegEd]

Hi. I use LP in my .45-70s, as well as lighter rifle loads.
Ed

[charlie b]

I thought LP primers were not as 'tall' as LR.

I guess I should measure some.

[Texas by God]

They aren't as tall and that helps to keep the primer from piercing from the average rifle firing pin. I have used LPP for cast loads in 22-250, 30-30 and 38-55 so far with no drama.

Sent from my SAMSUNG-SM-G930A using Tapatalk

[bedbugbilly]

Interesting . . . . I know that you can substitute SP and SR . . . but IIRC . . I've read on here in the past that you couldn't do the same with LP and LR primers due to the difference in the height of the primer. Obviously form those that have shared that they have it can be done - with common sense according to what the load is. In times of primer shortages - a good thing to know.

[Martin Luber]

Thanks...l think there are two levels of rifle loads with lead; The 12-1600 fps shotgun powder-4227 type loads.

Then there are the max velocity loads with 2000 + fps and lMR powders. Not sure these can all take LP primers but pressure is limited in lead so the answer may be yes from that viewpoint but unsatisfactory from ignition-performance aspects.
Thoughts?

[Martin Luber]

LP are shorter and can be used in rifle shells but LR are too tall for pistol brass. They won't feed in autos nor revolve in revolvers

[GBertolet]

LP primers are about .005 shorter than LR primers. I frequently use them in cast bullet rifle loads with easy to ignite powders. Pistol primers are good for about 40k pressure, so as long as your loadings are below that, there is no safety issue. In cold temperatures, with slow burning powders, I would be reluctant to use them. I would hate to have a squib, with a big buck standing in front of me. Be sure your firing pin has enough travel to reach the extra .005 distance. I have not yet found a rifle that would not set them off, although some have light primer hits due to the extra reach required.

[JimB..]

Around here LRPs are readily available, LPPs are not. That may or may not be a factor that anyone cares about.

[porthos]

would someone tell me the advantage of using pistol primers vs. rifle primers,

[Outpost75]

In some antique single-shot rifles, such as Ballards, in which the firing pin impacts at a steep angle in which the vector quantity reduces the striker energy, a pistol primer is helpful to reduce the incidence of misfires. In most cases a pistol primer can be safely substituted in a low-pressure load which is suitable for a plain-based bullet, at pressures below about 20,000 psi and about 1400 fps.

The caveat is that in milsurp rifles having driven protrusion greater than about 0.050" the pistol primer will seat deeper in the rifle primer pocket and "piston" back against the boltface such that the thinner primer cup will be drawn thin and suffer a ductile fracture at the striker indent, which will result in a pinhole rupture which pits and erodes the striker point. The key here is to stone the firing pin tip to a smooth hemisphere in which the driven protrusion is within the range of 0.032-0.040" for a large primer, or 0.028-.032" for a small primer, to avoid punctured primers.

[Green Lizzard]

I use them in my milsurp plain based match loads, the group are better

Bill

[Krag1902]

This is a timely discussion under the circumstances these days. I find myself down to less than 300 LR primers and none available locally. They are also out of every other sort of primer unless you go to a Magnum Rifle primer. I shoot almost exclusively 30-40 Krag loads at 1400-1500 fps. I have only Federal #155 Magnum Pistol primers to last me the rest of the shooting season. Would anyone have reservations about using these Federals in this type of load?

[Martin Luber]

Krag, l think you're fine with magnum pistol in your loads but that's only my opinion. I had 34 gr of 3031 with a cast 180 30 -06 and LPP, no issues. Why do I want to use LP? I have them. Rifle, not many.

[big bore 99]

I often wondered about this subject. What about a situation where you have a handgun and a carbine in the same caliber? Say for instance .45 Colt??

[charlie b]

If it is a pistol caliber, like the .45LC, then you will have to use pistol primers. As mentioned above, the rifle primers are longer.

If I were to use pistol primers in my cast loads I'd probably get the magnum primers. But, since I have enough LR primers I don't have to worry about that.

[tarbe]

This is a timely discussion under the circumstances these days. I find myself down to less than 300 LR primers and none available locally. They are also out of every other sort of primer unless you go to a Magnum Rifle primer. I shoot almost exclusively 30-40 Krag loads at 1400-1500 fps. I have only Federal #155 Magnum Pistol primers to last me the rest of the shooting season. Would anyone have reservations about using these Federals in this type of load?

My experiences over the past 5 decades says you won't have any issues.

If you are anywhere between Houston, TX and Romance, MO you can PM me and I can get you into some LR primers.

Tim

[reloader28]

The last big shortage we had a few years ago , I did a bunch of comparisons in my 257 changing ONLY the powder charge and worked up. Everything ran EXACTLY the same until I got to mid range loads. Past there I started piercing primers with LP.

For up to midrange (35,000+ psi) loads in my Roberts there was no difference in speeds, accuracy or anything. Ive had the same results in other rifles. Pistol primers seem to be good generaly for around 40,000 pressure in a handgun

This is my mileage. Everyone could vary.

[GregLaROCHE]

I often use LR magnum primers with my .45/70 loads.