I use a Dillon Square Deal B for my reloading, BTW.
Some more info...
It says "Colt Police Special .38" on the barrel, so it's definitely a .38. Too bad there is no way to upload a picture.. I know the gunsmith I took it to said to never use +P ammo in it. He said it would probably handle it but there was no reason to take a chance on such a nice gun.
I used my dial caliper to measure some bullets.
I checked 3 different .38 special factory loads and one .357 load. The diameters just below the crimp are .377, .377, .376 and .376. My handload is .380 so there IS a few mils difference in my hand load. But why would it go ALMOST all the way in. It falls right in just like the other cartridges... then it just stops before getting all the way in... leaving about a 1/4" of the cartridge hanging out. Is the hole in the cylinder tapered or something? Of course all these cartridges just fall right in and out of my stainless Ruger GP-100, which has had thousands of rounds run through it.
I can't really measure for any bore taper with just a caliper, so that's out. The bore size of the cylinder hole on one end is quite a bit smaller than the other, for about a 1/4" from the muzzle end. It's .356" on the muzzle end and .380" on the inlet end, exactly the same on both guns.
I sorted thru 12 rounds that I just loaded a couple nights ago to test a new load. 11 of the 12 drop right in the Colt cylinder. This 12th round hangs out about 1/4" inch. You wouldn't even be able to force it in. I tried it in all 6 holes with the same result.
All 12 of these bullets were loaded in succession, all parameters were the same, just different brands of shell casing, but it's all brand name once or twice fired brass with LaserCast SWC lead bullets.
The only thing I can figure is that there must be some amount of taper in the cylinder hole and with my handload at .380" diameter it's just right on the edge of going in or not going in.
I guess I'll just sort out the "fat" cartridges and use them in my Ruger and my Henry Big Boy. Kind of a PITA but I'm getting tired of taking bullets apart.
Which is another story all together. I'd probably relay some of the things I've learned over the last few years but I don't want to look like a dumb ass... I undertook reloading with great care... read a LOT of material on reloading, read thru zillions of forum posts and still wound up doing some pretty dumb stuff.
I'm sort of regrouping now and intend to run things by the forum BEFORE I do them.
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