Somehow I managed to find myself with 1000 cci 350 magnum large pistol primers, but the only cartridge I load that takes a large pistol primer is the .45 ACP.

Is there any danger in using the magnum primers in the .45 auto?

I use a medium load of 230 grain lrn over 3.9 grains of clays.

Can I get away with just dialing back the powder a little?

I wouldn't worry about it, Hodgdon lists 4.0gr as a max load but just using a magnum primer shouldn't increase your pressure much, if any.

If you're worried about it drop down to 3.5 gr and shoot away. As long as your gun will fire the magnum primers (they're often harder than standard) they should work just fine for you.

I'll second JohnK on this. I would back it down a little and see how it works. If you have a chronograph, see what the difference is and let us know. If your 45 has a lighter mainspring, which is often used in conjunction with a trigger job, I would avoid CCI primers, magnum or otherwise, for fear of a misfire.

exflatlander
Aggreed- you might see 50-100 Fps increase. Take a half of a gr off the normal load you use and work up, you should be fine:D

Thanks guys,

I thought I was on the right track, but I did not want to punch out 500 rounds and then find out I just wasted a bunch of brass, bullets and powder.

I will drop the powder and load up a small batch and see how they feel. Unfortunately I do not have access to a chrony so I cannot give actual results.

You do know you can pull the bullets and reuse the components if something did go wrong, don't you? So you wouldn't have wasted the brass/primer/bullet/powder, just the time it took to assemble the rounds and pull them apart.

Yeah I know you can pull bullets, I also know it is a major pain in the a&&!

I'd rather get it right the first time:D

No argument there! I had to pull apart 100 9mm rounds one time because they wouldn't cycle a Beretta. Max powder charge, powder was weighed as they were pulled just for some reason that batch of powder was way under power.

I wouldn't wish having to pull a bunch of rounds apart on anyone, but at least it's an option when you have to. :)

I like pulling bullets like I like going to the dentist. I would hand cycle the rounds through an auto before I pulled bullets.

John, that's what those 9mm/.40/10mm/.45ACP "conversion" cylinders are for in the Ruger Blackhawks! Easy, fast, and fun disposal of suspect auto pisto ammo.....

That would have been a much more enjoyable solution Mike, unfortunately a 357 Blackhawk is still on the "want" list and not on the "have" list. :)

John, next time, send that questionable 9mm ammo to me, and I'll 'disassemble' it, post-haste, with the Blackhawk.... LOL.... will return the brass & target(s)....