LR Primer v Standard

GJeffB · November 12, 2020, 11:06 PM

OK, you all know I cross post. Just for a variety of opinions ...

I try to pride myself on research. We've all discussed substituting components, and i received great help with substituting Large Pistol Magnum primers for Large Pistol standard. Thanks. Now, to continue hammering the horse ...

LRifle primers are really hard to find locally. My question does not deal with expensive hazmat fees.

Thanks to the community my .45-70 Cimarron Sharps 1874 is on the way and I can gather everything except LR primers.
I emailed Winchester, CCI, and Federal asking if I could substitute LR Magnums in a pinch, with appropriate reductions. All responses were the lawyer safe "no, you must not deviate." OK, fine. But I searched the interweb pretty thoroughly. The vast majority of various forum answers to the question was to the effect "back down 10%, no problem, work up from there, I/we do it regularly ..."

I'm not looking to sue anybody. I'm looking for actual experiences, please. Then there's the "in cold weather best to substitute magnum primers."

Background: loading handgun calibers since 1960's. Some bottlenecks 10+ years ago. Back into .45 colt, .45 acp, .38/.357. Straight walls. I realize .45-70 is tapered, lubed, etc. Got it. Bottom line: safe loading practices. Light/staring loads in .45-70 falling block, H4198 or AA5744. LR primers unavailable, is substituting LR Magnum acceptable on an ad hoc basis?

Thanks as always. You may find same/similar post elsewhere

-jb

zxcvbob · November 12, 2020, 11:34 PM

Big ol' .45-70? Of course you can use LR magnum primers. You probably won't even have to reduce anything, but back off 5% anyway from your tested loads (you probably dont have tested loads) and work back up just to be safe.

With a different primer it's a different load, but not all that much different.

Don't be tempted to use large pistol primers. They should be strong enough, and they are the right diameter, but they aren't tall enough so you won't seat them properly. Or if you do, your firing pin might not have a long enough reach.

Are you using black powder? (if so, don't reduce anything just go for it) Or Reloder 7? Or what?

totaldla · November 12, 2020, 11:40 PM

Yes you can use mag primers. I've chrono'd that in my 45-70 loads and with a fast powder like H4198 it doesn't make a difference.

Sharkbite · November 13, 2020, 11:49 AM

I dont have any experience loading 45-70, but...

I do substitute mag primers in one of my 300blk loads. The load uses H110 and calls for standard small rifle primers.

I live in the mountains of western Colorado and it gets COLD here. Minus zero for parts of the winter (burrrrr). Years ago, when working up this load, i was getting SD’s all over the place. I think temps were in the teens at the time. I backed down the load, used some mag primers and the load settled down and gave me good results.

So, now i use the mag primers for that load (110 & 125 gn bullets and H110).

GJeffB · November 13, 2020, 04:58 PM

Pretty much as expected.
zxcvbob: no, not black powder. "Light/staring loads in .45-70 falling block, H4198 or AA5744"

Thanks for the confirmation again. Guess I can't blame the manufacturers for sticking with the standard "do not change the components" reply. They have to CYA like most.

-jb

zxcvbob · November 13, 2020, 05:34 PM

Quote:

Originally Posted by GJeffB

Pretty much as expected.
zxcvbob: no, not black powder. "Light/staring loads in .45-70 falling block, H4198 or AA5744"

Thanks for the confirmation again. Guess I can't blame the manufacturers for sticking with the standard "do not change the components" reply. They have to CYA like most.

You did say that and I missed it.

"No not change anything" is for shotgun reloading. "This is what we tested" is for pistol and rifle data; be careful what you change.

November 12, 2020, 11:06 PM	#1
GJeffB Member Join Date: February 26, 2009 Location: Southern Colorado Posts: 68	LR Primer v Standard OK, you all know I cross post. Just for a variety of opinions ... I try to pride myself on research. We've all discussed substituting components, and i received great help with substituting Large Pistol Magnum primers for Large Pistol standard. Thanks. Now, to continue hammering the horse ... LRifle primers are really hard to find locally. My question does not deal with expensive hazmat fees. Thanks to the community my .45-70 Cimarron Sharps 1874 is on the way and I can gather everything except LR primers. I emailed Winchester, CCI, and Federal asking if I could substitute LR Magnums in a pinch, with appropriate reductions. All responses were the lawyer safe "no, you must not deviate." OK, fine. But I searched the interweb pretty thoroughly. The vast majority of various forum answers to the question was to the effect "back down 10%, no problem, work up from there, I/we do it regularly ..." I'm not looking to sue anybody. I'm looking for actual experiences, please. Then there's the "in cold weather best to substitute magnum primers." Background: loading handgun calibers since 1960's. Some bottlenecks 10+ years ago. Back into .45 colt, .45 acp, .38/.357. Straight walls. I realize .45-70 is tapered, lubed, etc. Got it. Bottom line: safe loading practices. Light/staring loads in .45-70 falling block, H4198 or AA5744. LR primers unavailable, is substituting LR Magnum acceptable on an ad hoc basis? Thanks as always. You may find same/similar post elsewhere -jb __________________ Spyros: People who talk little listen a lot. Which is why they're wise; it's harder to learn while talking

November 12, 2020, 11:34 PM	#2
zxcvbob Senior Member Join Date: December 20, 2007 Location: S.E. Minnesota Posts: 4,720	Big ol' .45-70? Of course you can use LR magnum primers. You probably won't even have to reduce anything, but back off 5% anyway from your tested loads (you probably dont have tested loads) and work back up just to be safe. With a different primer it's a different load, but not all that much different. Don't be tempted to use large pistol primers. They should be strong enough, and they are the right diameter, but they aren't tall enough so you won't seat them properly. Or if you do, your firing pin might not have a long enough reach. Are you using black powder? (if so, don't reduce anything just go for it) Or Reloder 7? Or what? __________________ "Everything they do is so dramatic and flamboyant. It just makes me want to set myself on fire!" —Lucille Bluth

November 12, 2020, 11:40 PM	#3
totaldla Senior Member Join Date: August 10, 2009 Location: SW Idaho Posts: 1,295	Yes you can use mag primers. I've chrono'd that in my 45-70 loads and with a fast powder like H4198 it doesn't make a difference. __________________ Lee Auto Bench Prime Castor Oil Case Lube

November 13, 2020, 04:58 PM	#5
GJeffB Member Join Date: February 26, 2009 Location: Southern Colorado Posts: 68	Pretty much as expected. zxcvbob: no, not black powder. "Light/staring loads in .45-70 falling block, H4198 or AA5744" Thanks for the confirmation again. Guess I can't blame the manufacturers for sticking with the standard "do not change the components" reply. They have to CYA like most. -jb __________________ Spyros: People who talk little listen a lot. Which is why they're wise; it's harder to learn while talking

November 13, 2020, 11:49 AM	#4
Sharkbite Senior Member Join Date: November 4, 2013 Location: Western slope of Colorado Posts: 3,679	I dont have any experience loading 45-70, but... I do substitute mag primers in one of my 300blk loads. The load uses H110 and calls for standard small rifle primers. I live in the mountains of western Colorado and it gets COLD here. Minus zero for parts of the winter (burrrrr). Years ago, when working up this load, i was getting SD’s all over the place. I think temps were in the teens at the time. I backed down the load, used some mag primers and the load settled down and gave me good results. So, now i use the mag primers for that load (110 & 125 gn bullets and H110).