Magnum pistol primers??

[Scott357]

I've been reloading 357 Magnum bullets for a while, and always use small pistol primers. What is the advantage, if any, do magnum pistol primers provide?

 

[t-squared]

A google search of "why use magnum pistol primers" resulted in a ton of good reading...mostly from various forums...but also this from CCI...CCI Ammunition - Primer Details

 

[Robert Richardson]

With some powders you will need them.

 

[OHOIAN]

For 357 mag, I always use magnum primers with W296/H110 and IMR 4227 powders. I use standard primers with Power Pistol and 2400 powders.

 

[jstory]

I use spp with 2400 in my 357 loads, never been a problem.

 

[dooshie]

I use spp with 2400 in my 357 loads, never been a problem.

same here

 

[oldpink]

As already mentioned, some powders do much better with magnum primers, specifically (also as mentioned) W296/H110, 4227, and a select few others that are ball powders intended for magnum loads that are difficult to ignite fully with regular primers.
H110/W296 in particular does its best at or near maximum levels, and magnum primers give that little bit extra spark to help get them there more reliably.
Magnum primers are also composed of slightly thicker metal to better withstand high pressure loads.

 

[Scott357]

I've been using only Titegroup and never had an issue. I will try a few with Magnum primers and see if there is a difference. Thanks!

 

[tranders]

Depending on where you are at with your Titegroup load, a magnum primer might create an over pressure issue. I have read to reduce your load by 10% when using magnum primers and then work up from there.

90% of all my reloading is done with Titegroup. I have never needed a magnum primer to ignite it.

 

[Leadeye]

Magnum primers I've saved for heavy loads of powder, especially when it's compressed. Like Old Pink said, H110/296/LilGun.

 

[prescut]

I buy standard pistol and magnum pistol primers at the same price. SPP works great most of the time. SPM works great all the time. I now only buy magnums. Some manuals say "not required". To me, that means using them is fine.

Reasoning:
Although it is widely reported that magnums can be 10 to 23% hotter, that does not translate to overall cartridge dynamics. Cartridge variables of powder type/weight, bullet type/weight, and seating makes up 99% of the cartridge dynamics. The primer might make a total of less than 1% of the makeup. Therefore 10 - 23% of 1% is negligible.

My testing has shown very little difference (25 fps) to none in velocity between types. I have never seen any pressure differences. I don't know a situation where magnum primers are contraindicated. The caveat like always is start your reloads at the low weight recommendation and watch for pressure signs. Does anyone know a recipe you would think should not have a magnum primers?

I have seen a clear reduction in unexpended powder granules, dirtiness, and brass stains. I shoot a lot of low weight cowboy loads and they can be dirty at low velocities/pressure. I used the magnum primers and that cleaned them right up without changing velocity/recoil. I like less cleaning.

How about you?

 

[mac45]

It's generally not a problem to use magnum primers in place of standard ones as long as you work up your load with them.
You can run into problems if you substitute a magnum primer for a standard in a load that's at or near max.
Handloader, (or maybe Rifle), did a write about it a year or so back. They got some pretty significant differences when they used a magnum primer in place of a standard in a near max load.

 

[oldpink]

It's generally not a problem to use magnum primers in place of standard ones as long as you work up your load with them.
You can run into problems if you substitute a magnum primer for a standard in a load that's at or near max.
Handloader, (or maybe Rifle), did a write about it a year or so back. They got some pretty significant differences when they used a magnum primer in place of a standard in a near max load.

OP, listen to this guy.
Following that will keep you away from disaster.

 

[1911ly]

Depending on where you are at with your Titegroup load, a magnum primer might create an over pressure issue. I have read to reduce your load by 10% when using magnum primers and then work up from there.

90% of all my reloading is done with Titegroup. I have never needed a magnum primer to ignite it.

Great tip. Titegroup is one of those powders that kinda scares me. You use so little compared to other powders. Gives max bang per pound, that's for sure. But I reload with it very carefully. I bought a 8 lb jug about a year ago and it doesn't seem like I have used any yet. lol

As mention up thread. Compressed or near max loads might benefit from magnum primers. But so far I am not having any issues with standard primers in 357mag, and 44mag. But I have stayed away from max and compress loads. Time will tell if I need them.

I'd try a few test loads and see what happens.

 

[Sniper 79]

Mags are for slow burning mag powders especially when it's cold out.

 

[jgressley2003]

I use mag primers in all my .357 loads. I had a shop owner say that W296 was a junk powder because it only ignited half the time which didn't make sense to me at the time because I never had any issues, but after reading an article in Handloader W296/H110 require them. He was so used to using 2400 so I'm sure it never crossed his mind that you would need anything other than a regular primer.

 

[oldpink]

I use mag primers in all my .357 loads. I had a shop owner say that W296 was a junk powder because it only ignited half the time which didn't make sense to me at the time because I never had any issues, but after reading an article in Handloader W296/H110 require them. He was so used to using 2400 so I'm sure it never crossed his mind that you would need anything other than a regular primer.

Yep
That shop owner was obviously a fool because he failed to notice that any reloading data for W296/H110 indicates that magnum primers are the order of the day.
It's amusing to hear about someone who thinks that particular powder is "junk," though.
I have yet to find anything else that performs quite as well for serious performance out of my .45 Colt, and the three deer I've taken were all downed by loads stoked with max charges of it.

 

[singlesix]

I use Remington magum primes, well because they were on sale for $25 vs. $31. I use Titegroup and don't load anywhere near max for my revolver, I still have all my fingers and toes.