Henry Rifle Forums

I have been looking for a long time now for small pistol mag primers and can not find any. I did find some small rifle mag primers and the one sale person told my he use them. I am shooting them out of a rifle. so hope the will work ok. I am planning on using HP-38 (because that is all I have and can get) 6.5 gr. with 158 gr. flat top bullet. I have been shooting all my 357's with just plane primers but really want to shoot them with mag. primers. What do you all think?

Target sports announced 10% off ammo and primers for members today

There are lots of people who use small rifle primers for both pistol and rifle. You should be fine. I have done it the only difference is the primer face is a little tougher on the rifle primer. Where you are using them in a rifle anyway I dont think you will have any issues. Now if you try them in a pistol and the pistol has a lighter strike they may not go off. You just need to try them and see.

Galen wrote: ↑

Wed Oct 04, 2023 3:19 pm

I have been looking for a long time now for small pistol mag primers and can not find any. I did find some small rifle mag primers and the one sale person told my he use them. I am shooting them out of a rifle. so hope the will work ok. I am planning on using HP-38 (because that is all I have and can get) 6.5 gr. with 158 gr. flat top bullet. I have been shooting all my 357's with just plane primers but really want to shoot them with mag. primers. What do you all think?

I use both regular and mag primers. I cannot see/feel or tell the difference when fired. I also use small rifle/pistol primers interchangeably. Except for military small rifle primers. These I use rifle only.

I've never used any mag primers before, I believe they are just a tad hotter than normal.
Side note, I do have 1200 LR mag primers. Two hundred were giving to me, and well the brick I picked up by accident some years back when I grabbed two of what I thought were reg LR. I'll find a use for them one of these days.

RP

Galen wrote: ↑

Wed Oct 04, 2023 3:19 pm

I have been looking for a long time now for small pistol mag primers and can not find any. I did find some small rifle mag primers and the one sale person told my he use them. I am shooting them out of a rifle. so hope the will work ok. I am planning on using HP-38 (because that is all I have and can get) 6.5 gr. with 158 gr. flat top bullet. I have been shooting all my 357's with just plane primers but really want to shoot them with mag. primers. What do you all think?

I've done a bit of experimenting with small rifle primers in the .357 but for a different reason than yours. I've got a quite a few of both rifles and revolvers in .357 and three of them have occasionally pierced pistol primers and there is no obvious flaw in the firing pin shape. I cautiously started substituting small rifle primers which ended the piercing issue and with the powders I use there were really no dramatic changes in accuracy or even on the chronograph.

The latest Hodgdon manual shows a starting load of of 6.2 gr. of HP38 (same powder as Win 231) at 33,700 CUP and a maximum of 6.9 gr. of HP38 at 40,000 CUP with a small pistol magnum primer with a 158 gr. jacketed bullet. I'm wondering if using a small rifle magnum primer might have a more profound effect on a fast burning powder like HP38 than it did on the slower burners I was using? There are other variables such as bullet style and seating depth etc. but if it was me I'd back off a bit on the charge on a fast burner with a hotter spark. You can always work back up. FWIW

Target Sports USA had them this morning, free shipping if you buy the brick and 10% off.
Midsouth Shooters Supply had free haz mat last week and tons of primers in stock.

Sign up for email alerts, these are 2 places that have been very good in the past.

Paying 100.00 per K for primers to me is insane. Especially on line. Time you get the freight and haz on there its even more.

I did some test using same loads in various calibers using standard and mag primers and never saw any difference to worry about. Was using a chrono and checking the target. My LGS has a bunch of small pistol primers standard or magnum but only one box of the large pistol primers.

fortyshooter wrote: ↑

Fri Oct 06, 2023 9:24 pm

I did some test using same loads in various calibers using standard and mag primers and never saw any difference to worry about. Was using a chrono and checking the target. My LGS has a bunch of small pistol primers standard or magnum but only one box of the large pistol primers.

That was my experience also when going from small pistol primers to to small pistol magnum and even to small rifle standard. The OP is talking about small rifle magnum and my thought is that combination could get a little squirrelly with a near max load of fast burning powder. I never tried it.