There's a Dillon 550B in my house that's turning out 45 ACP 230GR FMJ like we're going to war. The powder charge, OAL, and brass resizing doesn't drift but at the atomic level. Life is good. Fast forward to three days ago. I have this idea to switch to a 200 Lead Semi Wad Cutter (LSWC) for a target load out of my favorite 1911. About 4 grains of BE would be the answer here. This is a nice winter time project. I run a few through the Dillon and out comes the Midway 45ACP chamber gauge. The trouble now begins. The loaded 200 LSWC rounds do not fit into the chamber gauge. If the don't go into the gauge, they sure as heck aren't going into the gun. The round appears to be fat, leaving the tail end of the round outside the end of the chamber gauge. What's going on here? The 230 FMJ are 0.452 and the LSWC are 0.452. The FMJ totes out at 1.26 OAL and the LWSC at 1.24. These are Oregon Trail Laser casts, by the way. Both the 230 and the 200s are crimped to 0.457. I've run the crimper die up to almost being out and then down the the plate with not much effect. So what needs to be done to pass the chamber gauge test? Inquiring minds want to know.