10mm Auto primer question.

Awesymoto

Awesymoto outdoors
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I'm new to 10mm loading, and bought a ton of federal 180 FMJ ammo to get familiar with my new G20 and get some brass... Well suprise suprise its small pistol primer sized brass. Published load data seems to be on large pistol primer brass only.

Has anybody loaded 10mm with small pistol primers? I may be able to get small pistol magnum primers as well, and am thinking maybe the small pistol mag primers may be better due to it originally being designed for large pistol primers.

I have really only loaded for my rifles and 9mm before, so I'm not super familiar with pistol reloading stuff.

Thanks in advance
 
Mag or non will have more to do with what powder than anything else. Large doses of slow powder are usually what call for Mag primers. I honestly don't recall ever using a mag primer in 10mm. I wouldn't be too concerned about standard small primers if you're starting from scratch and working up a load... then sticking with small pistol primers.

I do recall a few people saying that had some issues with small primer 45ACP when they tried using their same old LPP load with SPP, but what exactly that issue was, I don't recall.
 
Kinda a long way to answer your question, but several years ago I has 3 blown primers in a row while testing some 22 BR loads.
pulled the remainder of the loaded ammo and found 4 spp. At that point I sold all of spp . Fast forward to last year when I got a 9 mm. So , I started loading test rounds with srp. I traded for some spp and tested both side by side , and couldn't tell much different with any of the powders I tried. Cost and availability might be a factor ?
 
Ive never used mag primers in 10mm but I do like Longshot as my powder. You could also just get Winchester primers which are for both mag and standard
Im going to load 10MM with longshot and wondering if you did some accuracy testing and what powder you used. Also did you use std or mag primers for the Longshot?
 
I've only loaded LPP for 10mm but I load a lot of 45ACP and (unfortunately) have a few hundred SPP cases (drives me nuts sorting brass) but I use the same load for large and small primer cases.
 
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I read where 10mm and 45acp brass with small primers are generally used for indoors target shooting. I always look at the primer size when buying pistol ammo because I want to keep it all the same size primers when reloading.
 
I'm new to 10mm loading, and bought a ton of federal 180 FMJ ammo to get familiar with my new G20 and get some brass... Well suprise suprise its small pistol primer sized brass. Published load data seems to be on large pistol primer brass only.

Has anybody loaded 10mm with small pistol primers? I may be able to get small pistol magnum primers as well, and am thinking maybe the small pistol mag primers may be better due to it originally being designed for large pistol primers.

I have really only loaded for my rifles and 9mm before, so I'm not super familiar with pistol reloading stuff.

Thanks in advance
Use CCI 300 Large pistol primers exclusively in G20 and Starline Brass with Blue Dot and BE-86
 
I have "switched" to small primers in the 10mm platform for my 9x25 Dillon handloads (10mm necked down to 9 and blasting light bullets out at Warp Speed), as I can push pressures a bit higher without expanding case heads and primer pockets. I also recently bought a thousand rounds of 10mm FMJ Blazer ammo, and they have small pockets as well. In my opinion, the 10mm should have originally been specified with the SPP instead of the LPP. These are not rifle-sized rounds that might need a lot of primer power to light off the powder, after all.