[Jayhawker]

Hello:

I have a shooting buddy who says he has never found it necessary to use magnum primers in his .357 when using heavy loads with H 110, Win 296, Lil'Gun or IMR 4227 powders. He says the only exception to this is when he knows he'll be shooting when its very cold otherwise he always uses standard , small pistol primers. Having just acquired a new .357, I'm anxious to try some full-on loads with it but before I start loading, I was wondering how his use of primers sits with this group.

Thanks for any input.

Pete

[mtnbkr]

I've always used mag primers with H110. While I haven't tried a standard primer with it, I've heard too many accounts of hangfires and other issues to bother experimenting with it myself. With heavy charges of 2400, I've tried both ways and I get a few fps more with mag primers, but ignition seems to be the same. I've even used mag primers with Bullseye when I didn't have anything else. With the light loads I was using, I couldn't tell a difference.

That said, I'd probably always use a mag primer with any powder that nearly fills the case (like H110 and 2400 do). It just seems like a lot of powder to be lit.

I for one would like to know HOW a mag primer is different from a standard primer. Is the flame hotter? Does it burn longer?

Chris

[stans]

I would and do use magnum primers for H-110 and W-296. Seems to me the magnum primers burn hotter in order to ignite the slow burning powders. The increased heat must increase the pressure inside the cartridge and that would make ignition more reliable and more complete.

[Kamicosmos]

I have a few experiences to add on this:

I have tried standard primers in full house H110 loads in both .44 and .357. While I had no hangfires, I did have inconsistant burn rates which resulted in lots of unburned power in both calibers. I have much better results with mag primers in both calibers.

I think the mag primers generate a bit more pressure. Back when I and a friend (Black Snowman here at the forums) first started loading for .40, we accidently used some small mag pistol primers. (In a glock, even!) No kabooms, but we did notice a significant increase in the size of the bulge near the base of the cartridge case. Where that pressure comes from (hotter burn temp, more of it) I couldn't say.

[Okiecruffler]

I tried standard primers in my Contender 357 H110 loads and the results were very disappointing. Accuracy when from 1/2" 50yrd groups with mag primers to well over 2 inches with frequent fliers. Also probably the dirtiest load I've ever fired due to all the unburned powder. I have used standard primers in my 44mag 2400 loads with good results.