One of the things I've preached on this blog is that when times are good, you should stock up on items that will be hard to get during a panic. One of those things is a good supply of primers if you're a reloader.
Last Fall, I bought a case of 5,000 CCI Large Pistol Primers. I use LPPs for loading .38-40, .44-40, and Magtech brass shotgun shells. If I ever get around to loading .45 Colt I'll use LPPs for them as well.
For loading .38 Special, .357 Magnum, 9mm, and .32 S&W and .32 S&W Long, and .32 H&R Magnum, I need Small Pistol Primers.
Guess who forgot to stock up on SPPs before the panic hit? Guess what is virtually impossible to find now?
Before the COVID-19/race riots/election year panic set in, I thought I had around 5K SPPs. In reality, I have about half that.
So, a few weeks ago I wondered if it would be possible to convert .38 Special brass to accept LPPs. I did some research online and found that in fact, there used to be factory loaded .38 and .357 ammo which used LPPs.
Since LPPs may contain a bit more priming compound than SPPs, if you do this, reduce any maximum or near-max loads by 10% and work on up.
This page has a chart listing the minimum and maximum dimensions of both primers and primer pockets.
To modify the primer pockets I used a .210" chucking reamer with a stop collar on it to set the depth. The stop collar was made from 1/2" 6061 aluminum rod. It's held in place with an M4 screw I had in one of my miscellaneous parts bins.
To use it, I chucked deprimed a .38 Special case in the lathe and held the reamer in a drill chuck in the lathe's tailstock.
Note that because in a lathe the workpiece rotates, not the cutting tool, I don't need to be concerned about the stop collar being unbalanced due to the set screw sticking out.
I found that because of the small clearances, brass chips built up between the head of the case and the collar. I had to withdraw in several times per case to clear the chips with a brush and pick. It was slow going.
But eventually, I converted five cases to accept large pistol primers. To test, I seated CCI LPPs. They seated easily, maybe a little too easily. It might be better to use a .209" diameter reamer because .210" is the maximum for large primers.
I plan to do another 5 cases tomorrow and then load them will mild charges so I can test them on my next trip to the range.
During the Obama-era panic, some of the primer shortfall was made up by imported primers. I'm hoping that the same will happen this time around.
And you can be damn sure I won't be caught short again.