Home Forums Reloading Handgun Reloading AA#9 Data Discrepancy 10mm

So I have recently started loading for my 10mm G40 with KKM barrel.
I had loaded some 180 XTPs today with AA#9. My Hornady Manual(#8) said 14.9grs was the maximum with this bullet.

Loaded some at 14.4grs and they were approaching 1400FPS according to my chrono. Pretty hot.
14.6 was over 1400 near 1450

Decided not to go any further and researched.,
Hodgdon and Accurate’s data show 13.5 is the max with this bullet with a 2.150 vs 2.160 OAL

A chrono shot says the 13.5grs load is 1300 from my gun.

Just a heads up.

Cool, at least Hornady is consistent. Haven’t trusted their data since the early 90’s.

I just recently started loading for 10 MM again. I had made a note in the Hornady manual that their top load left ugly spent primers. 14.0 left the primer looking OK...

I now have a functioning chronograph and worked up to AA #9 load data max of 13.5 that gave an average of 1250 180 XTP Glock 20 factory barrel. I'm still planning to try some longshot loads and will report back.

What cartridge are you loading?

my experience the Hornady data with AA - 9 powder is hot....

Yep it is hot 10mm

Probably safe but I just decided to back it down.
I figured that XTP would probably explode at 1400-1500fps

FYI-

Accurate Arms (TN) #9 powder is a ball powder.

Accurate (MT) #9 powder is a double base spherical powder.

IF/When your selection was bottled by Hodgdon, it's anybodies guess what's in the container.



Speer Gold Dots will handle more pressure & shoot more accurately than a Hornady XTP.

Hornady’s newest data has 14.2 grains max with 180 grain XTPs. I ran into the same issue a couple years ago. 14.5 grains was seriously hot at 1340 fps. I stopped there to look into why the velocity was so high and found the following information:

If You look on their website under support, load data, HANDBOOK ERRATA,
Hornady Handbook of Cartridge Reloading – 10th Edition Errata
Page 910, 10mm Auto – 180gr data section, do not exceed 14.2 grains of Accurate No. 9 powder.

Thanks for that info scout. My old notes said that the 14 grain loads "seemed" fine but I didn't like the looks of 14.5 at all. When the light conditions are good for my fussy choregraph I might try bumping the 13.5 180 XTP back up toward 14 again.

I have a good supply of Longshot to try as well.

I just ran into this recently in my Springfield XDM 10mm. I only went up to 13.8 gr of Accurate No. 9 and man it packed a punch. I was getting upwards to 1275 fps. When I got home, I compared my Hornady manual to all my other manuals and Hodgdon online and the highest load with any 180 gr bullet and Accurat No. 9 was 13.5 gr.

CCI 350 work great with AA9 in 10mm

Great choice KKM did you put a heavier spring in also ?