Reconfirming Magnum Pistol Primers OK for Regular Loads

I know it’s discussed as a given around here using magnum primers is ok for light loads. Well, I proved it to myself this AM.

I used two common 45ACP loads for me—230gr (P)RN w/4.6gr of Accurate #2 @1.240” and 200gr (P)SWC w/5.1gr Acc #2 also at 1.240 using both CCI 300 and 350.

I noticed no difference between primers or anything else.

 

That powder does not require a Magnum primer.

 

Are you able to chrono to detect any difference in velocity?

 

I’m well aware of that. The point is, if magnums are all one has, they are safe in lower power loads. This is a fairly common question on this and other forums. I tested it for myself.

 

No, but I’m always tempted to spend more money.

 

Do they work, yes. Some guns might not like the harder cup. Some loads will produce higher sd numbers. If your loading hot for power factor switching primers needs to be done with consideration.

 

I wouldn't give it a second thought, esp in 45. I myself have a fair bit of mag spp and only use them in h110 357 that I am going to start using in 9 and 38.

 

Right. The thesis was for light loads.

 

Such a different response these days from when I started not quite 3 years ago. I had inadvertently bought CCI 550 SPM primers with my first powder and bullet purchase. I wasn't even aware of my mistake until I'd loaded 200 rounds. Anyway...I took a bit of a spanking from experienced shooters for having used magnum primers in my very first 9mm loads. It hurt so badly that I haven't touched those primers since. That's right....I still have 800 of the first primers I ever bought.
I'm guessing that once I feel comfortable sitting down I may break out those primers and use them...but it will be a while. Thanks to the Mrs for insisting I buy a ton of primers heading into this situation so that I have the luxury of leaving 800 primers untouched.

 

Glad you recovered. I read every forum, blog, website before I even bought my large pistol magnums. The common refrain was light loads, light loads, light loads. So, since that’s mostly what I load, I bought some to give them a try. And today was my first shot. Everything went fine.

 

from https://www.shootingtimes.com/editorial/loads-for-the-bullseye-shooter/99418:

It's worth pointing out that Winchester and Remington make only one type of Large Pistol primer. Winchester posts on its primer boxes that they are appropriate for standard and magnum loads. This differs from CCI and Federal who both make two types of Large Pistol primers: standard and Magnum.

This means for many things magnum primers are fine if that's what you have. Just work the loads up as normal.

This is also true for handgun rounds using small pistol primers. Some folks use small rifle primers for handgun ammo. That's okay, too. Just work the loads up as normal. I, and many others, have used small rifle primers in their 9 Major and 38 Super loads. The only thing here is whether the gun will reliable set them off. Some striker fired guns have issues with rifle primers.

 

Good to know. The only issue I've ever had with magnum versus standard primers is cost and availability. I've used magnum primers in non-magnum cases for slow powders in sealed breech actions for a while but not in older guns where even a little change in the pressure curve could spell danger. "Could" being the key word. I'm too old for a new nickname like "one-eye" or "lefty."

 

Great article. The article essentially says if you got em smoke em.

 

Be sure to work your loads up as normal to avoid any surprises. This applies to us whenever we use components different than are listed in the load data were refer too - whether it's bullets, case brands or primers.

 

Basically the purpose of the magnum primer is to better ignite slower burning magnum powders. This is accomplished by providing a longer spark (brisance)!

Here is a lengthy article that provides information and answers just about every possible regarding primers.

https://www.sksboards.com/smf/index...6fb6135clb3k4&topic=56422.msg646510#msg646510

My personal testing 9mm loads using medium burn rate powders yielded around 25 fps increase at minor power factor with no signs of excessive pressures.

Smiles,

 

Yep and again, that’s how this all began—light loads.

 

There was a big article in my old Lyman manual about how some were way more powerful than others. Maybe over time there has been efforts to normalize the power of them.

 

The Lee manual says in bold to only use magnum when called for by the data. Don’t recall actual language.

 

I don't load anywhere near max, and with the current situation on primer availability I buy any I can find if the price isn't ridiculous. I've found very little difference between magnum and standard primers in my guns without adjusting the loads, at least according to my chronograph. I've also ran some small rifle primers through my 9mm M&P's and they've always fired. My own real world experience is what guides me, regardless of what somebody else may think is right.

 

Well I agree with the sentiment completely, but still prefer someone else to take the first hit. So tell me more about the small rifle primers.

 

Fascinating. Thanks for the reprise.

 

I remember reading that a long time ago. I lurked here for a few years before joining and read mostly the tests and load data. As I recall, the knock on using rifle primers in pistol cases is/are the slim chances of: A) a failure to ignite in striker-fired pistols - which you kind of confirmed - and, B) the possibility of a slam-fire due to the difference in seating depth/primer height between rifle and pistol brass - which I believe only applies to large rifle, not small rifle and did not happen in your testing. Great topic.
(edited to correct typo)

 

Two things:
1. You mean “not small rifle,” correct?
2. When/how would a slam fire occur?