Large Pistol Primers for BP Loads

[Chief TC]

I have been successfully using WLR primers in all my TD and Sharps 45-70 BP loads. I have read many folks use LP primers. I am interested to know from BP shooters here if they have experiences and opinions using these. Also, if I have great loads with WLR, is there still a reason to experiment with LP primers. Thanks.

 

[hawg]

You can use them with light BP loads. I don't think I'd want to use them with a full case of BP. The LP primers are thinner and there is a height difference. The LR primers are taller.

 

[.38 Special]

People are using pistol primers in BP .45-70 cartridges? Why? That seems like a terrible idea.

 

[hawg]

People are using pistol primers in BP .45-70 cartridges? Why? That seems like a terrible idea.

It doesn't seem like a good idea to me either but they are doing it with plinking loads.

 

[.38 Special]

It doesn't seem like a good idea to me either but they are doing it with plinking loads.

Is it just because of difficulties finding the right primers?

 

[Chief TC]

I have read some things in magazine articles and other BP forums about how they are a touch lighter in igniting the powder and lends to better accuracy. But like I said, I want to hear from people with personal experiences. While I am not saying I don't trust the authors of credible magazines, I still think it is better to hear from many that had been there and done it for themselves.

 

[Navy Six 2]

Having subscribed to "The Blackpowder Cartridge News" since the beginning I have read warnings that using pistol primers in rifle cases can cause breechface damage. Since the pistol primers are shorter in length than rifle primers, I believe the idea was that upon firing the short primers begin ejecting from the pocket then slam into the breechface.

 

[.38 Special]

I have read some things in magazine articles and other BP forums about how they are a touch lighter in igniting the powder and lends to better accuracy. But like I said, I want to hear from people with personal experiences. While I am not saying I don't trust the authors of credible magazines, I still think it is better to hear from many that had been there and done it for themselves.

Huh. I proved to my own satisfaction, decades ago, that the long range competitors were right: the hottest primers I could get my hands on cut down SD and improved long range groups. I can't imagine any benefit to switching to the wrong primer.

 

[troy fairweather]

No problem at all, lrp hold up to many magnum pistol cartridges so the low pressure from black powder even a full case is fine.

 

[hawg]

Having subscribed to "The Blackpowder Cartridge News" since the beginning I have read warnings that using pistol primers in rifle cases can cause breechface damage. Since the pistol primers are shorter in length than rifle primers, I believe the idea was that upon firing the short primers begin ejecting from the pocket then slam into the breechface.

I find that unlikely. You're only talking about .008 difference and the breech face is a lot harder than primer material. I'd be more worried about blown primers. Pistol primers are thinner.

 

[MEHavey]

There isn't any 45 caliber rifle case-load of BP that's going to exceed the pistol primer's pressure regime
Including the big one's I've been loading up to 45-3¼"
45-90 here: https://thefiringline.com/forums/showpost.php?p=6798243&postcount=18

I use pistol primers in all my BP-loaded BPCRs

 

[Carl N. Brown]

I can't find Large Rifle Primers locally so I am using Large Pistol Magnum Primers this year.
I am not seeing any signs of trouble.
(6.5 Carcano, 38 grs weighed Triple7, 160gr bullet.)

 

[MEHavey]

Go ahead and use regular primers.
BP ignites very easily, and burns best in a undisturbed column

 

[Captain*kirk]

I've never seen any reason to use anything other than LR primers in my .45-70 Sharps loads.

 

[Chief TC]

Thanks for all the replies everyone.

 

[Zygodactyl]

For my trapdoor, I use the recipe in Spencer Wolfes book. He recommends Magnum Large Rifle to better ignite the compressed black powder charges. I was skeptical of this and tried regular primers also. In my 55 gr loads I didn't see much difference but for a full charge heavily compressed I can see it would make a difference. His book is mainly for recreating the cartridges designed for the TD.

I would worry about LP primers being pierced and damaging or fouling your bolt face.

 

[MEHavey]

would worry about LP primers being pierced and damaging or fouling your bolt face.

Check/Google references for BP-loaded cartridges... nothing exceeds 20-25,000 psi (measured), even for big-cartridge/duplex loads

Black Powder Pressure

Just about every load data chart for smokeless includes the pressure data for each charge, boolit weight and speed. Why don't we see pressure data for BP? Any thoughts on this?

castboolits.gunloads.com

One doesn't even approach pistol-primer pressures limits.

 

[Jim Watson]

I have seen the same reports as #7 by Navy Six.
It SHOULDN'T matter, but some say it DOES.

There are BPCR shooters using "primer wads" to soften ignition. Feed a slip of paper between the case and the shellholder and let the primer cut its own wad.

 

[MEHavey]

upon firing the short primers begin ejecting from the pocket then slam into the breechface.

ALL primers back out of their case across (at a minimum) the distance of headspace gap, and "slam" into the bolt face upon firing.
The primers then reseat themselves as the case moves/stretches back to meet that same bolt face.

If the primer/bolt can withstand that movement/re-seating at 62-63,000 psi, it can handles 20,000
~~~~~~~~~~~~~~~~
As to "primer wads" I've generally put a disk of newspaper at the inside/bottom of the case for the same "softening" purpose.
Putting it in the primer pocket itself is an interesting idea.....

 

[Dave T]

... I have great loads with WLR...

If it ain't broke, don't fix it. Unless of course you just like messing with stuff.

When I find a load that duplicates the original BPC performance, my load development is done. YMMV!

Dave

 

[Ugly Sauce]

I've used both, (just experimenting) and don't really see any difference. But I don't shoot over 100 yards, nor do I worry about a 1/4" larger group. With Winchester Large rifle primers, 80 grains of 3fg, and the Speer 400 grain JSP in my Marlin, I'm quite satisfied with the accuracy and can't imagine (although possible of course) any improvement by going to Large Pistol Primers. So, I see not reason to experiment with large pistol primers, unless your rifles are producing half-inch groups at 100 yards, and you want to get that down to one-quarter inch. !!!!!!

 

[Chief TC]

Thanks everyone. Yes, I like to experiment but I don't have a use for LP primers if they don't work well in my BP 45-70 loads. I found LR magnum loads do not work well for me. I suspect that if people use very compressed loads, the magnums may work well. For me, standard flash hole and LR primers with around 64grs is the ticket for me. I don't mind chasing the perfect load but there is a limit on construction. I am not going to create wads for primers. Just not going to do it. Especially for my TD. Now if I get into long range competition with my 45-90 that is on its way in a few months and find people are winning with that combo? Ok, then I will look at it. I love BP shooting but it has more voodoo associated with it than smokeless development. I'm Catholic, so I guess I'll sprinkle more holy water over my creations. I'm kidding. A good sense of humor in all things is healthy.

 

[whughett]

I have read some things in magazine articles and other BP forums about how they are a touch lighter in igniting the powder and lends to better accuracy. But like I said, I want to hear from people with personal experiences. While I am not saying I don't trust the authors of credible magazines, I still think it is better to hear from many that had been there and done it for themselves.

A few months ago I purchased a Pedersoli heavy barrel Sharps in 45/70. Due to a lack of large rifle primers I use Federal Large Pistol primers of which I have a generous supply.
Loading 65 grains of 2F under a 405 grain bullet. Using a drop tube then a compression die, the bullet is just touching the powder surface when seated.
I’m only 100 rounds into shooting this rifle and so far there has been no indication that the primers are failing in any aspect. Not flattened, the firing pin isn’t punching thru and no leakage.
Using the drop tube I can get the full 70 grains in the case then use the compression die to avoid compressing the powder with the bullet. I’m still in the process of finding the best powder charge for accuracy with the full effect of this big rifle.
My only point here is I haven't experienced any safety issues using the pistol primers.
I can’t speak to any other aspect as I’ve never shot any other load thru this big rifle. BP, even at these higher charge loads are tens of thousands of psi below smokeless loads. I’d advocate a cautious approach using pistol primers if I were to move in that direction.
Also powder Inc has large rifle primers at $98 a k, one per person, I bit the bullet and ordered a brick so for now the large pistol primers will be reserved for the 44 and 45 pistol loads.

 

[Driftwood Johnson]

Howdy

I have been using Federal Large Pistol primers in all my 45 Colt, 45 Schofield, 44-44, 44 Russian, and 38-40 Black Powder ammo for years now. No need for any magnum primers, Black Powder is easier to ignite than some Smokeless powders.

I use Large Rifle primers in my 45-70 BP Ammo. I use Winchester, because that is what I have had on hand for years now.

 

[hawg]

Also powder Inc has large rifle primers at $98 a k,

That one caught me by surprise until I remembered Powder Inc includes the shipping and hazmat fees in the price.