[stumpjumper]

I just noticed that I have some magnum primers mixed in with my "regular" primers and have loaded some 9mm with them(300 rounds). The load is 4.4 Titegroup,115 fmj, 1.125" OAL. I have "searched" and have gotten mixed opinions. If I shoot them out of a full size 9mm, will I be OK?

[stumpjumper]

To answer my own question, I just got back from the range and didn't have any problems.

[2alphas]

I had a similar experience only with 40 S&W. I normally use Standard Small Pistol primers, 3.8-4.0 grn Titegroup w/a 180 LRN Moly bb. Functions well for weekly matches that do not require 165+ power factor to make Major (at real matches I use 4.7 Titegroup yielding around 168-170 PF). Getting back to the Magnum primers, I just dumbed down the powder charge to 3.4 grn Titegroup and the rounds worked fine. I didn't chrono them, but recoil felt the same as the 3.8 loads. If I actually worried about this, I would contact Olin Corp (maker of the Winchester primers I use) and see what they would have to say. One observation though, Winchesters' LARGE pistol primers box states "For STANDARD or MAGNUM pistol loads". I figure if it didn't matter for the larger bb's (45 ACP), it shouldn't for the 'lil' guys'. Hope this helps.

[GioaJack]

Originally Posted by 2alphas

One observation though, Winchesters' LARGE pistol primers box states "For STANDARD or MAGNUM pistol loads". I figure if it didn't matter for the larger bb's (45 ACP), it shouldn't for the 'lil' guys'. Hope this helps.

Actually it's the other way around. The .45 is a relatively low pressure round with quite a bit of leeway when it comes to pressure concerns.

9 mm, .40 cal and 10 mm pose more potential pressure concerns than does the .45. A general rule of thumb is to reduce your loading by 10% when using magnum primers if you're anywhere near max. If you're at or near a starting load magnum primers are really a moot point.

You are correct about Winchester... they stopped marketing separate standard and magnum primers years ago.

Happy shooting.

Jack

[stumpjumper]

Thanks for the info. I believe that at 4.4, I'm under the max (4.8)The rounds shot fine, but didn't come to any factory loads.