Don't try this at home, kids - Hand Loading

American Handgunner, May-June, 2003 by Charles E. Petty

Everyone makes mistakes. It's human nature. But what we'd rather, not do is make them in front of a crowd of witnesses who see, and know, exactly what you did wrong and are not at all bashful about rubbing your nose in it.

Let me present the new 10mm Petty Awshit.

It was really just a simple case of mistaken identity, which, tragically, took place in front of a crowd of other writers. We were getting training on Oehler's Model 43 Personal Ballistics Laboratory. With it the hobbyist can get remarkably accurate measurements of chamber pressure by simply gluing a small strain gage over the chamber of the gun. Two wires are soldered to the gage -- routed through a controller that plugs into a laptop computer. The results are very much like those used in industry from equipment that costs tons more.

Most of my work used Contender barrels in a wide range of calibers. The gun is mounted in a Ransom Rest and one of the precautions taken is to be sure the wire doesn't get pulled off the gage. First the gauge is covered with a blob of fast-setting epoxy to protect the connections and then a coil of extra wire is taped to the barrel to provide a little slack if the wire gets jerked anyhow.

The wire is taped to the barrel with black electrician's tape. As luck would have it the best place to put all that stuff is right over the markings on the barrel. No trouble. We are, after all, highly trained professionals who can tell those things at a glance.

So when I got ready to shoot the .357 Magnum I picked out the barrel, wired everything up and fired the first shot. The report was a weak pop and there was no reading of pressure or velocity. The case that came out was fat in the middle and reasonably normal at both ends. You could also see the impression of rifling on the forward quarter inch and the middle was expanded by .05". Much to my surprise the case wasn't split, since brass stretched that much usually does. I caught a lot of grief over that. Don't know why, for all I had done was fire a .357 Magnum cartridge in a 10 mm Auto barrel.

Some other interesting oops include firing a .40 S&W in a .45 ACP and 9mm Luger in a .40. Wait, you say, both those cartridges will fall right through the barrel. And so they will, were it not for a handy gadget called the extractor. You'd think that loading the smaller cartridge in the wrong magazine would be very noticeable, but loading magazines is' such an automatic thing we do it almost unconsciously. If the cartridge is held by the extractor it will almost surely fire.