I Almost Know What I’m Doing

Today I got back to handloading, although I should not have. I was supposed to wait for a new Glock barrel.

I’ve been trying to develop a load for 9mm semiwadcutters. I could not find a recipe for the bullets I bought, so I looked for something close, dropped the charge down something like 8%, adjusted the overall length (OAL) for longer bullets, and made test rounds. I got up to 5.5 grains of BE-86, which is the flash-suppressed version of Power Pistol.

The recipe I started with came from Alliant, the manufacturer of BE-86. It was for 125-grain lead round nose bullets. They got 1179 fps at 5.7 grains, and for 9mm, that’s a nice speed. It’s supersonic at the muzzle. They recommended an OAL of 1.120″. They didn’t say how long their bullets were. I used a Laser Cast 124-grain bullet as a stand-in, and it measured 0.06″ shorter than my semiwadcutters. I figured that meant I needed 0.06″ more length to get a similar case volume, but I didn’t want long bullets hanging out of my cases, so I tried 0.04″.

When I shot these things with 5.2 grains, I got an average of 1082. That was not too bad, but it wasn’t 1179. I knew Alliant had probably tested its rounds with a longer barrel, so I didn’t expect to equal their speed, but I figured I ought to be able to hit 1125. This was a wild guess. My barrel is 3.43″ long. I figured it was probably 50 fps slower than a full-size Glock barrel, which comes in at about 4.5″. This is sort of consistent with wildly varying figures from the web.

When I moved up to 5.3 grains, I got a very small increase in speed. I got 1088. The velocity spread dropped, however, going from 65 to 14. I thought that was nice. Then I moved up to 5.5 grains, and I got 1078 fps and a spread of 51. I had actually gone backward.

I sought advice and read up. Some people say that when you plateau with a given powder, it’s time to quit adding weight.

I thought maybe I should give up and try Accurate No.7. I didn’t want to do that. I wanted to find a use for my BE-86, and although it will sound silly, I could swear BE-86 feels better when I shoot it. It seems to feel friendlier and less snappy. I noticed this while working on 10mm rounds, and today BE-86 felt good while I shot 9mm.

Then I read up on barrel leading.

Glock barrels are polygonal, which means the bores are shaped like hex nuts with rounded corners. Ordinary barrels have grooves. The raised parts between the grooves are called lands. Polygonal barrels are not optimal for lead ammunition. Lead can accumulate in them, and if it gets bad enough, it can cause obstructions and explosions.

I had been under the impression that hard lead alloys were okay for Glocks. That was what past research had told me. While I was working on this latest load, I read that many people disagreed. I read that an amount of lead which seemed very insignificant could slow bullets down and cause case overpressure.

Okay.

Now I had some decisions to make. Should I buy coated bullets and throw out my lead bullets? That would take a while, given the ammunition panic. Should I buy a new Glock barrel made for lead? Should I go ahead and shoot lead and not worry?

I finally decided to spring for a Storm Lake barrel made for lead. I’m waiting for it to arrive.

Today, I forgot about that, and I decided to make several rounds of ammo with shortened cartridges. I knocked 0.020″ off.

I had been wanting to shorten the cartridges anyway because they have lube grooves with wax in them. A lube groove is a slot that goes around a bullet near the base. It’s okay to have lube grooves exposed. It won’t affect how the ammo works. It is ugly and messy, however. I wanted to reduce the amount of exposed wax, but shortening a cartridge too much can cause overpressure.

What the heck. You only live once. On Earth. Not including the Messianic Age. I decided to try it.

I cranked out a few rounds, and I tried them. I got an average of 1112 fps with a spread of 24. This was much better. I looked at all the cases I could recover. The primers looked okay. I could see tiny bulges near the rims. I tried shoving spent casings into a cartridge gage to see how bad the bulges were. It was possible to jam them in, and after running a spent casing through a sizing die, it dropped it without a problem. I figured I was safe.

Now I’m almost supersonic at the muzzle. Should I try to do better? I don’t know.

If I get, say, 1150 fps, I’ll only be around 35 fps above the speed of sound, and I assume that would drop off to subsonic a short distance out. Does that mean anything with pistol rounds? Will it have a noticeable effect on accuracy? Probably not. If it did, I’m sure it would be the talk of the forums. Everyone who shoots accurately would want to stay above or below the speed of sound.

I am tempted to shorten the cartridges to the point where the lube is covered. It might give me better speed with no ill effects. I think I’m pretty cautious. The web is full of people pushing 1300 fps from bullets this heavy, and I would be excited if I could do 1175.

I’m anxious to settle on a recipe. I need to get this 9mm lead loaded so I can move on to other things.