6.5 TCU Question

[cherokee5425]

I am getting a T-C 14" barrel in 6.5 TCU. Several years back I had a 14" barrel in 6mm TCU. I have a goodly supply of once fired and loaded 6mm TCU ammo. My question is can I fire the 6mm TCU ammo I have in the 6.5 TCU barrel to fireform it or should I pull the bullets and resize them to 6.5 TCU?

[Slowpoke Slim]

I would definitely pull them. They may go bang, but I wouldn't recommend it. You will not get a good gas seal, and the neck will be unsupported.

Also, if this brass is only once fired, you may not lose any when you neck up to 6.5. Depending on your 6.5 sizing die, you may only need to lube the cases and run them through the FL die in a single pass. Probably wouldn't hurt to lube the inside of the case mouth. Just be sure to clean the lube out of the neck before loading.

I have a 6 TCU myself. I used new Lapua brass for mine. I did lose 2 pcs of brass in the first batch (shoulders crumpled) when I was only running the virgin brass through my FL TCU die. After that, I switched methods, and used a 6mm expander mandrel in my Sinclair expander die. Never lost a one after that. I use Imperial sizing wax, and just a very small dab on the expander every 2 or 3 pieces of brass kept me out of trouble.

[Ladobe]

Anybody who would promote this foolhardy idea is irresponsible for any of several reasons (whether you might get away with it or not).     IOW, don't do it!

Pull the bullets and powder, neck up , full length size bumping the shoulder and go through the steps to develop a safe load for the new barrel.

I doubt you'd even need any inside lube to neck up in this case even if the brass has more than just one firing if the brass is clean.   But as suggested the Imperial would work very well, but will also require being cleaned back out of the case neck and cleaning the die(s).    Main thing to remember with the Imperial is to use it in micro quantities.   It goes a long, long way, and unlike the liquid lubes it builds on itself.    Most people tend to use far too much and that can lead to problems.    IE... even when preforming wildcat brass necks, shoulders and in some cases the body of the brass from scratch I did just fine going 10-12 or more cases with each sparse application of the wax.

FWIW