rcbs carbided dies

Loading 44 mag and they are a little buldged at the bottom of the case. There is a little at the top with a 300 xtp. So it looks like a hour glass effect. Loaded 180xtp and just a buldge at the bottom. Called rcbs and they said it is fine as long as they fit the gun. They also said that when you use there carbide dies that is what you get a hour glass. Something tells me that is not right. I know you all can't tell me much unless you do them your self. I do know it is happening when I size them. there is about .010 between dies.

I think I understand what you are saying. I have had the same effect on some of my 44 Mag rounds. The resizer actually reforms the case, but when you seat the 300 XTP it is larger diameter than the specks of the sizing die.

I have a couple that I will take pictures of and post them latter… Lets see if we are talking about the same thing.

It's actually fairly common on straight walled cases. I've had the same issue using Hornady dies with my 458 Win and Lott mags as well as RCBS, Redding and Hornady dies on straight wall handgun rounds. The die is cut a little small in diameter probably from a worn reamer just like Ruger cylinder throats so the case is sized down a little tighter. So far I haven't had any accuracy issues from it. I think it's luck of the draw because I also have dies from all of the above that leave nice straight cases. Bottom line if they chamber and shoot straight then there shouldn't be any problems.

That is the way they seem to work. The sizer sizes slightly smaller so that the expander has something to work with. All my straightwalls look a little thinnner in the middle, wish I did ;-)