PDA

View Full Version : How is Autocomp powder in 9mm Luger using Lee 124 grain truncone?



Linstrum
12-08-2011, 03:14 AM
Last year I got a pound of Winchester Autocomp pistol powder, but I haven't tried it in my 9mm pistols yet. I did use it in my Citadel 1911A1 .45 ACP and it worked fine without any complaints - I was shooting 18-inch groups at 100 yard targets using it, which is no big deal with a pistol that groups small. Just hold high and walk your shots to the target to get the range. Anyway, the Winchester Autocomp loading data for the 9mm Parabellum shows a rather narrow 1/2 grain usable powder range (4.8 to 5.3 grains) with 130 grain projectiles. The Lee 9mm 124 grain truncated cone weighs in at 130 grains using the particular wheel weight alloy I use. Because the 1/2 grain range is a pretty small spread compared to Blue Dot, which I normally use, I would like to know if anyone else has tried the combination of Winchester Autocomp powder with the Lee 9mm 124 grain truncone so I can get an idea of which end of the powder load spread this particular combination favors. One thing about Lee's 9mm 124 grain truncone is that it sits a little deeper in the cartridge than other cast projectiles do, so pressures tend to be on the high side with this projectile because of the reduced case volume.

The pistol I want to try the Autocomp powder in is a Browning High-Power that is from the Israeli police. My pistol is marked "FABRIQUE NATIONALE HERSTAL BELGIQUE Browning's Patent Depose", so it is the real thing. From what I read it was made in the 1970s or 1980s. It does quite nicely with factory copper jacketed ammo, around 6" at 25 yards. I want to see if I can get group size down a little more. I also have a 9mm Cz-85B pistol that on the outside is almost identical and performs the same.

I like the truncone style boolits in my 9mm and .45 autoloader pistols because they feed well and have pretty good accuracy. In the 1910s the German military did experiments using truncones and found they had good performance and "stopping power". Because of war atrocities during WW1, the Germans discontinued using truncone pistol ammunition to avoid having German POWs executed instead of simply being interned in POW camps.

rl 1029

bobthenailer
12-08-2011, 08:59 AM
Ive never used auto comp ! i think it is made for the action shooting crowd for use with compensated handguns to make the comp more efficent . Im sure it has other uses but that was there main goal .
IMO as far as the 9mm goes i would recommend , TC bullet profiles , 124 gr or heaver bullet ,
and a bullet size to .357 to .360 dia , you will have to let the gun tell you what dia it likes best.
Use casings of the same brand and if youre reall serious? resize that brand of brass and discard cases under .750 in length , and if possible seat bullet out to enter throat and still feed in the magazine.
If you remove the magazine disconnect on the HP [ this is so it wont fire without the mag in the pistol ] you should get a better trigger pull.

In my witness tz 75 i use the saeco #377 124 gr tc bullet sized @.357 dia with sorted by length r&p 9mm cases , cci 500 pri , and 4.5 grs of power pistol for 1 3/4 groups at 25 yards from the bench with a red dot installed for accuracy testing.

Linstrum
12-15-2011, 05:42 AM
Hi, bobthenailer, thanks for the reply, sorry for not getting back to you sooner.

Yeah, Autocomp is meant for pistols with compensators. It has a prolonged high pressure curve and as such I would think it would have a bit more muzzle flash than other powders. If it does have a bright muzzle flash, then that could be bad at night in a defense load. But beyond that potential drawback, I'd like to find out just what this powder does in my 9mm Browning High-Power and Cz85B.

I kind of wondered about the magazine-trigger interlock mechanism, thanks! I'm glad to know it can be disconnected to improve trigger pull. Actually, the trigger pull is not all that bad, but it is a police pistol and it does have a bit stiffer pull than my Cz85B.

The particular Lee 124 grain truncones I have drop from the mold at 0.360", and I just slugged the High-Power and Cz85B bores and they are both 0.357" across the widest pair of lands. I made 0.3585", 0.358", and 0.3575" sizing dies, so the 0.3585" sizing die I use for my .357 Magnum S&W Model 19 revolver will probably be okay for these 9mm pistols, too.

rl1042

bobthenailer
12-15-2011, 08:53 AM
I was told that Power Pistol also has more muzzel flash than normal ! but i have never tried it in a low light enveroment . but it was the most accurate powder bullet combo in my TZ 75. I tried tight group , universal clays , wsf , wap & HS6 powders

Lee W
12-15-2011, 07:18 PM
I used AutoComp when I started casting for 9mm . My thought was water dropped WWs, sized .357 in front of 4.4 grains of AutoComp would be the ticket in a G34.
It has been great for at least 5000 rounds and it will always be used.

Linstrum
12-16-2011, 07:21 AM
Hi, Lee W, thanks for the input. The 4.4 grain load is the starting point listed for 130 grain projectiles and the 1/2 grain usable range made me wonder which end of the load range that powder favors, know I know.

Cheers! :drinks:


rl 1046