I noticed last night that the RCBS 45-270 boolits I was sizing were .453" on the lower driving bands, but .455" on the front band. I knew there was no way they would chamber in my RBH, and that I needed to run them deeper into the sizing die. The problem was, I didn't have any lead shot big enough to plug the top two sets of lube holes. Number 6 was 'way too small, and it was the biggest I had. I tried a couple of things that didn't work, then remembered some .006" stainless steel shim stock I had. I trimmed two squares of that big enough to cover the holes, and held it in place with electrical tape. Worked beautifully.