10MM Reloading Questions

Bought a G20 awhile back. This is the only pistol I have loaded for, so I am somewhat ignorant to pistol reloading. I loaded up about 30, 180gr HP's with 13.2gr Accurate#9. I have virgin SIG brass and magnum pistol primers. They cycled awesome. No stamps or other signs of pressure.I went up to 13.5gr and the gun jammed a couple times, and split two pieces of brass. Blew the primer out of another. Just comparing to what I read online, I didn't think the load would be that hot. Also, should I be sizing the Virgin brass? I am just using a strait seat die with no crimp. The gun is for protection, so I don't plan on re using brass at all. That gun slings them lol, and trying to find them is not worth my time. Don't plan on shooting it that much either.

Only pistol and you start out with a 10mm, eh? Bold move, I like it. Edit, misread your post. Disregard.

The thing you have to appreciate with pistol reloading is how important OAL is. You listed most of your load details except that, which makes me concerned you didn't pay much attention to that. Lots of 180 JHPs will have different profiles, so you can't just start with a random load. If e.g. that's an XTP and you are using an XTP recipe, sure you can have more confidence.

I reload 180 JHPs (a few different kinds) for 10mm, but not with AA9, so I can't speak to that in particular. Usually a crimp is used in pistol laods to remove the bell from the sizing die at least. Lee FCD is hands down the best there, and it's cheap.

Basically it sounds like your load is too hot, did you work it up? If not, go do that for your specific bullet and OAL, and consider a light crimp just to remove flare/bell.

In GRT both of those loads are grossly over pressure with a 180 Speer GD. Using the COL for my G20, your loads are showing over 40,000 psi

I just cowboyed it and went with the above info. It was for a 180gr pill. My COL is 1.260

I had tons of trouble loading 10 mm with range brass fired out of glocks .I used them for my 10 mm carbine .It was fine for medium loads buy when I used near max loads the brass blew apart and would probably messed up a glock bad .I have not tried new brass yet but I will be soon .I used 800 x for 40 sw carbine loads to 1200 fps the same as a 10 mm pistol not shabby .I hope this tnw 10 mm carbine works out check it out uses glock mags and has interchangeable barrels and calibers even 460 roland .it's the tnw carbine .

But is it the same bullet listed there (an XTP I assume)? I haven't ever sized virgin brass. It also seems unlikely, but it's possible the un-crimped bullet was set back during feeding. Try pushing the bullet into the case and see if it moves. But really, do a workup.

Eric_F said:

But is it the same bullet listed there (an XTP I assume)? I haven't ever sized virgin brass. It also seems unlikely, but it's possible the un-crimped bullet was set back during feeding. Try pushing the bullet into the case and see if it moves. But really, do a workup.

Click to expand...

At this point I need to do a work down lol!

Starline has the best brass of all for heavy loads and general use .Raven reloading on here has boxes of 2000 pcs for $237 that's half price of statline .I use Hornady xtp bullets too .They seem to hold up very well .Irs the only bullet that I trust in my 357 rem max at 2000 fps .They shoot good in my carbines in 10 mm and 40 sw .I had the crimp problem with those once fired glock brass I tossed it all except for med loads .

Are you using a fsctory barrel? Some of the earlier glocks did not fully support the entire case which can cause all kinds of problems when loads get near the top end. Also to answer your question, yes you need to resize new brass

wvbearhunter said:

Are you using a fsctory barrel? Some of the earlier glocks did not fully support the entire case which can cause all kinds of problems when loads get near the top end. Also to answer your question, yes you need to resize new brass

Click to expand...

IIRC, this is also one of the reasons they do not recommend hand loads; perhaps someone can validate. For this reason, I have not reloaded my G40 yet. I have, however, purchased an aftermarket barrel already.


Sorry, the pictures are not as clear.

If you're splitting cases and especially blowing primers you're probably way over pressured. The load manuals are just a guideline so I'd drop down the charge and do a taper crimp on a dummy round. And then cycle the dummy to see if the COAL is changing while feeding.

Yes factory barrel. I will back them down. I had seen on forums guys running up to 14.5gr with no problems on the G20's. I can't attest as to if they were using factory barrels or not. I didn't think 13.2-13.5gr would be that drastic. I am going to get them down to about 12gr, cycle a couple, and see how they do.

Did your loads pass the plunk test at that OAL? Take your barrel out and make sure they can spin freely when fully chambered.