substitute primer (magnum for small)

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Guillermo

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Greetings,

Small pistol primers are hard to get a hold of.

Can a magnum primer be substituted and if so, what accommodations must be made?

FYI, most of what I am loading now are low pressure 38s for IDPA.
 
;):)Small Rifle primers also.

I came across a deal awhile back on Remington 6 1/2 Small Rifle Primers that I have loaded in most all small pistol cases with complete success. Small rifle primers in general will work for most small pistol loads. Just be sure to back off of your starting loads 10% and work back up from there...Bill.
 
So if the load calls for (example) 5 grains...load 4.5?

(example...I am loading 38s for IDPA...jacketed flat nose, 4.6 grains of Winchester 231...I should load 4.1 grains w the magnum primers?)


sorry for the dumb question...just making sure I understand because that seems like a LOT.
 
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Another seemingly dumb question.

If one can use less powder...why would you not substitute on a regular basis?

Any downside?
 
Another seemingly dumb question.

If one can use less powder...why would you not substitute on a regular basis?

Any downside?

None that I can think of. I use Small Rifle Primers in place of Small Pistol Primers, only down side to this is if you have a handgun with a weak hammer/firing pin spring you may have a FTF. I have not had this issue with any of my handguns however.

NOTE: Do Not Sub Large Rifle Primers in place of Large Pistol Primers. Large Rifle Primers are taller and will not seat flush or 2/3 thousands below flush.
 
I reload most every handgun cartridge in the mid range. I reload for accuracy, doesn't take much to kill paper. My reason for loading midrange is because of arthritis in my hands, wrists, and arms, and I do not like pain. If I was loading anywhere near max I would drop 10/15% and go from there.
 
If one can use less powder...why would you not substitute on a regular basis?

In truth, there are too many variables in play to know what the magnum primer will do, so the 10% decrease is just a safety margin. It does not mean that the performance of the round with a normal primer/powder charge and the one with a magnum primer and 10% less powder will be the same. This varies by cartridge, case capacity (based on bullet length and seating depth), primer manufacturer and choice of powder.

You might find that dropping the powder charge by 10% and using a magnum primer produces a too-soft load and that you need to work back up to the performance you were getting before, and that by the time you get there you're so close to the original charge that your powder savings are negligible.
 
Thank you very much for the advice.

I am going to buy a thousand magnum primers to get through the next month and then "clean the shelf" next time I see standard small pistol primers.

I will keep good records so that I have a "work around" in the future.
 
Rifle primer cups are usually harder. Aside from possible light strikes, this means that loose primer pockets might theoretically need more chamber pressure to seal. Just something to keep in the back of your mind. You might want to periodically inspect your ejected cases for carbon spots on the case head, and your breechface for signs of gas cutting.
 
I had the same primer problem with m44 mag once. Could only find magnum. I was loading my standard universal clays load. I called hodgon and he said that all of the website data was with using magnum primers. So I bought the magnums and didn't worry about it.

I'm not sure if he was saying all as in all loads period and he might have just meant 44 mag.

Bottom line is just call the powder manufacturer. They should be able to tell you something concrete.
 
During the primer shortage four years ago many people had to substitute mag small pistol primers for standard one. Reduce the charge a bit if you are at max by the book, or max on a worked up load that is at or near max. With a charge like you ask about a .1 Gr reduction will likely result in similar velocities. .2 at most.

Problems? In general, the least violent primer that ignites the powder well is going to be better for accuracy.

But hey, which one of us is good enough to prove it in a hand gun? Not me. :)
 
when you use small rifle primers, how much do you down load?
If MAX load for XXX bullet, with XYZ powder is 5.0 grains, then back down your charge to a starting load of 4.5 grains and work up from there.(.5 grain is 10% of the MAX load of 5.0 grains)

As stated, the only issue that you MAY have would be light primer strikes with a "Tuned" handgun due to a harder primer cup. This has not been an issue with me..Bill.
 
Be sure to keep the pressure up on small pistol loads using small rifle primers so the harder primer deforms enough to seal the primer pocket or you could get gas cutting.
 
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