COAL and Accuracy in 9mm


Well-Known Member
Oct 1, 2009
North Chuck, SC
I have been working up a load for 9mm using 231 and Precision Delta 115gr fmj with mixed cases.
It's being shot in a G17 with a Lone Wolf barrel.
This was all shot at a an indoor range and I was having to deal with targets swaying to some degree.
I had a number of fliers, no bad ones and they may have been my finger rather than the load.
None have been run across the chrono yet.

I find that the minimum powder charge of 4.5 at a coal of 1.135 is soft and drops the brass at your feet.
4.8 feels more along the lines of factory and gives the brass a bit of a toss.
Accuracy is better than WW white box.

Just out of curiosity I decided to play with coal and powder charge a bit and see if I could improve it.

I loaded up some at;

4.5 - 1.130
4.5 - 1.135
4.8 - 1.130
4.8 - 1.135 (best string of the day)
4.8 - 1.160

I found all to shoot better than white box all to cycle the gun just fine.
I seems the 4.8 loads shoot more to point of aim than 4.5
Offhanded accuracy I couldn't really give the nod to any one specific load and coal.

My determination is that any of the above listed loads are going to shoot better than white box.
I am surprised the difference in coal did not make more difference in performance.

My next step is load another round using the two best and only one type of case.
I really need to stop the targets from swaying.
I am going to go to the outdoor range where I will have a possible crosswind but at least my target won't move and I will shoot from a rest
This is one of those times it would be really nice to have a Ransom rest.