9mm: AA #9 Powder Chronographing

Disclaimer: All of the following loadings were taken either from gun powder reloading manuals or other reloading manuals that may vary in powder charges greatly. Various components combined, make all the difference in the world. I am not responsible for your actions. Always refer to official reloading manuals when reloading. As usual, I must say that this information is what works for me. Use your own common sense. You are responsible for your own actions!

I've been doing a lot of 357 SIG caliber testing. I thought it might be interesting if I could develop some good 9mm loads using the same gun powder, primers, and bullets that I use for the 357 SIG. Obviously, AA #9 would not be one's first choice, second choice, or even third choice for the little 9mm round. In fact, it's kind of difficult to even find AA#9 reloading info for the 9mm. The 13^th edition of the Speer's Reloading Manual came through.

So, in order to show you that I'm not a complete 357 SIG bigot, here's my 9mm info:

 I used a CZ 75 BD pistol (decocker model) with a standard 4.7" barrel.

124 grain West Coast Copper flat point bullets; Winchester primers; mixed brass; 1.073 Over-All-Cartridge-Length (OAL).

AA # 9 gun powder; the following charges are based on the Speer Loading Manual.

The results were much better than I was expecting. In fact, I could have had even better stats if I had used only one brand of brass and individually weighed each test load. But I just cranked out each load with my Dillon 550 progressive press, as usual.

As expected, the 9mm was approximately 200 fps slower than the 357 SIG round, and that’s comparing my Glock 31 4.5” barrel with the CZ 75 BD 4.7” barrel.

As you can see, the brass pressure ring expansion was minimal. I did notice that the PMC brass expanded a bit more than the other brands I was using (see 10.0 row above).

The compressed AA#9 powder seems to work very well, just as it does in the 357 SIG caliber. Note: I did not reset my OAL each time I changed the powder charge. It was always set for 1.071. The compressed powder actually pushed the bullet up a little higher each time the charge weight increased.

For the IPSC Production Class, it looks like 9 grains of #9 with a power factor of 129 & and energy rating of 298 is a perfect match with my CZ 75 BD pistol. J

Now, here's a chart using a longslide Glock 34 with a 5.32" barrel. As you can see, the G34 could squeeze out another 40 - 70 fps. It actually hit 1302 fps with the maximum powder charge, which roughly equals a 3.5" barreled Glock 33. On the other hand, the Glock 34 has a lot less perceived recoil than the little Glock 33 shooting an equivalent powered round. On the other hand, the Glock 33 is a lot easier to carry concealed. OK, that's enough of this game. Oh, and based on the brass pressure ring, it appears that the Glock chamber is a bit tighter than the CZ pistol:J