9mm 124gr + HP-38, what's the recipe?

[UpTheIrons]

Greetings, all!

Having figured out the whole reloading process with .45 ACP, it's time to move to 9mm to keep my wife from shooting up all my ammo! I know that med had an issue in his SR9c with Accurate #2, so I'm hoping to head off any issues at the pass, as it were, since that's what my wife shoots, too (albeit with about 400 rounds down the pipe).

I've got Zero 124gr FMJ bullets and Hodgdon's HP-38 powder along with Winchester SP primers and mixed once-fired brass.

Hodgdon's site only has HP-38 listed with 125gr FMJ bullets (4.4gr to start, 4.8gr max load and a min. OAL of 1.090").
Lee's manual lists the same starting, max, and min. OAL numbers for a 124gr FMJ.
Lyman (49th) has nothing for 124gr bullets, and uses Win 231 for a 125gr JHP (3.9 to start, max of 4.4, 1.075" OAL).

Since the bullets are within 1 grain of each other, do the Hodgdon and Lee numbers look like a good place to start? Or should I be more conservative and use the Lyman numbers, since HP-38 and Win 231 are identical?

I'll run 10 rounds of the starting load and creep up from there with other batches of 10 until I hit the sweet spot.

[MoJo]

Use Hodgdon's data. They are the manufacturer of the powder. 1 grain of bullet weight won't make a difference in the starting load. Lyman is very conservitive.

[Beiruty]

why can't you start with 4.5?

[UpTheIrons]

Thanks, MoJo. That's what I was thinking, but I wanted some independent confirmation with my first high pressure rounds. I may run 4.5gr, since that's what my Auto-Disk throws. One cavity down throws 4.1 and the next one up throws 4.7, so I'll see what happens tomorrow when I get it all full of powder in the morning light.

[UpTheIrons]

Well, here's what happened this morning. I loaded two sets of 10 rounds as follows: 124gr FMJ, Win SPP, 1.124" OAL, one set had 4.5gr HP-38, the other set had 4.7gr. Hodgdon lists 4.8 at the max load, so I was a bit hesitant to be so close to the top, but that's what my Auto-Disk choices were.

The target on the left was the 4.5gr rounds, the target on the right was from the 4.7gr ones. Two hand stance at 7 yards. I could definitely feel the power difference between the two, and the 4.7gr load felt more like a factory round. I think I'll continue with that load, since the accuracy was so much better. Didn't think it would be that much, but it is what it is. I could have tightened the groups up a little more, but it was a rushed range trip and I was really there to function test the loads more than anything. I didn't expect so much of a difference.

[NcongruNt]

It's pretty amazing what a difference a couple tenths of a grain will make. I have a .380 load using Bullseye that tightens up between 2.3 and 2.5 grains out of my LCP. Everything around that more or less imitates WWB with its poor grouping. If you can get a drum powder measure and tune them by hand, you may be able to tune this load even further, varying down to .1 grains for your workups. I don't have a disk measure, but I hear there is the add-on adjustable charge bar that will let you tune your charges with a finer degree. They only look to run $8 or so... something to look into.

[MoJo]

Did you actually weigh the charges your auto disk was throwing or were you going by the charge tables? My auto disk consistently throws light. I agree on the adjustable charge bar or the double disk kit. I have both, they make the auto disk a very versatile powder measuring system.

The heavier charge looks to be the better load go with it.

[UpTheIrons]

Did you actually weigh the charges your auto disk was throwing or were you going by the charge tables? My auto disk consistently throws light. I agree on the adjustable charge bar or the double disk kit. I have both, they make the auto disk a very versatile powder measuring system.

The heavier charge looks to be the better load go with it.

I did weigh them separately. The chart was off by + or - 0.1 grains for each disk cavity from what my scale showed, so I figured it would all work out in the wash. I'll have to get the adjustable charge bar, then, since everyone who uses it seems to like it so much.

Thanks!

[Luggo1]

I load Montana Gold CMJ 124 grain, at 4.2 grains, with a target OAL of 1.135. Occasionally I bump it up a 10th or so, but this is my basic load for training, Saturday IDPA. Sanctioned matches, I'll usually shoot factory because I haven't been able to chrono this load.


I need to correct this post...4.2 grain is of Titegroup...serious brain fart.

I use about 4.4 grains 231/HP 38

Sorry

[NcongruNt]

I load Montana Gold CMJ 124 grain, at 4.2 grains, with a target OAL of 1.135. Occasionally I bump it up a 10th or so, but this is my basic load for training, Saturday IDPA. Sanctioned matches, I'll usually shoot factory because I haven't been able to chrono this load.

I like the Montana Gold stuff. I go with the 124 grain FMJ myself. Good stuff - consistent and well-finished.