Can it be done? Building a wildcat that is a 6.5 Sherman. Am wandering if u can use the chamber reamer to open up a 280 AI seater die to use for my 6.5 Sherman? Using a .264 mag neck die to form the false shoulder and then fire forming. Resize the necks and ready to load. Just not sure what to use to seat with. Was gonna use a .264 mag seater but am thinking the that the .270 parent case would move around too much in the larger die and not give me a straight bullet seat. Going to have a custom set made but was wandering if this can be done for now while its taking 3-4 months to build the dies.

Thanks Roy

There are blank seating dies you can buy that you can use a chamber reamer to make a custom seater. But most commercial seating dies are hardened and you'll ruin your reamer if you try and use it to open them up.

Al.. how will that wilson seater work? Looking over dimensions of the 280AI and the 6.5 Sherman they r very close. The Shermans case walls are blown out a little more. Where the case wall meets the 40° shoulder it is .006 larger.
Thats why i was wandering with auch minimal stock if the chamber reamer could open it up just a bit to snuggly hold the case while seating the bullet.


Roy

As already mentioned, if you run the reamer into a hardened seater die you will ruin the reamer. Best solution is to make a new seater with the reamer from a die blank or a chunk of free machining steel. If you insist on using an existing die it would have to be lapped out, which would take a while and you need to know what you are doing. Might be able to open it up with a carbide boring bar and then lap, but the little bar is going to be way up in there and is going to want to chatter.

Can a hardened die be honed on a diamond hone?


Roy

I posted the link as the fastest way to get a seater.....just run the finish reamer in a smaller .264 die that will clean it up completely. Cheaper only if you're set up with an arbor press.

You might be able to get away with using a small carbide boring bar like one that Circle Machine manufactures and some really careful planning. I've used them over the years to cut experimental chambers and to open die bodies to give shoulder room and change neck diameters. While not as pretty as a factory produced die, they can do the job until a better one becomes available.

If the seater die is hardened (some are not), it can be annealed then re-chambered. This can be done with a sizer as well after which it is re-hardened. I wouldn't bother hardening a seater and don't harden any that I make. Sizers, I carburize and case harden. GD

If for whatever reason you prefer a threaded seating die, Troy Newlon makes great die blanks. -Al

http://newlonprecision.com/