Here's a question for those of you who own 6mm TC-U barrels. What do the fired cases look like? What do your dies make them look like? The reason I ask this is, I have a 6mm TC-U reamer from Clymer. It is the same thing as a 223 Ackley Imp necked up to 6mm, just like the 6.5 and 7 versions. But today I was looking at the Accurate Powder reloading book, and it shows the 6mm version as a straight neckup of the 223, with a 23 deg. shoulder and same diameter body, where the 6.5 and 7 are different. I would like to use my reamer some day, but I don't know what 6mm TC-U dies will do to a case, nor do I know what the chamber in Contenders looks like. Can anybody help? Thanks!