looking for help loading subsonic 9mm

[lewmed]

 I recently purchased my first pistol suppressor an Obsidian 9 and have been experimenting loading some clean burning and quiet ammo. For my first loads I've chosen RMR 147gr jacketed RN bullets, CCI # 500 primers and VV N320 or N340. Both powders seem to work well with a 3.8gr to 4.1gr charge with 3.95gr of N340 being the best. I've never loaded 9mm subsonic ammo before and would like to hear from someone with expertise.
Thanks lewmed

[jwc007]

I would stick with the N340, but what was your velocity at that Powder Charge?

My favorite loadings with 147 grain Bullets in the 9mm used HS-6/W540 producing around 950 fps.

[lewmed]

 I'm not sure of the velocity only 5 of the 10 rounds I tested with 3.95 gr. of VVN340 were recorded on my chronograph before it started raining cats and dogs. The high was 910 fps and the low was 886 fps with a avg. of 898 fps.

[jwc007]

I'm not sure of the velocity only 5 of the 10 rounds I tested with 3.95 gr. of VVN340 were recorded on my chronograph before it started raining cats and dogs. The high was 910 fps and the low was 886 fps with a avg. of 898 fps.

A velocity around 900 fps with a 147 grain Bullet gives you a Power Factor at about 132, which is a pretty good level for a target load.
You might consider loading a test batch of the VVN340 3.95 grains or similar loading for more extensive testing, but I think you are close to what you need.
If you desire a bit more power, then you can go from there.

[Wobbly]

- The main reason to stay with the Vit powder is the amount of residue left inside the can. With any of the N300 series powders there will be hardly any. The fastest powder will be the cleanest.

- You might look at N330 as being a viable compromise between N320 and N340.

- Of course the can will affect the velocity, but to get a feel for these new loads you can always consult our CZF load data on each of those powders. It's at the bottom of THIS PAGE. Look for loads that result in velocities lower than 1000 FPS.