New receipe

IMO you have two choices with a powder that slow: either you go out and get some big magnum rifles, or start loading cast bullets for your .308. There are exceptions (for instance I have used published RL22 loads for the 6.5Swede, etc.) but by and large slow powders are designed with large capacity cases in mind. Can you get any data from either the manufacturer or importer?

I'm not much into shooting the shoulder mounted artillery, others can happily tell you what they know about possible uses in them, but I do cast, load, and shoot a LOT of rifle bullets. Most shooters never consider shooting cast in their rifles these days, but it is well worth the effort for accurate low cost target loads, but with faster powders even short range (200yds or less) deer hunting loads.

Very slow powders can be fantastic with low pressure cast bullet rifle target loads in medium capacity cases, and I regularly burn up a lot of WC860 launching cast bullets from 150-200gr in .30-30, .308, 7.5Swiss, .30-06, and 8x57Mauser. (IMR7828 and RL22 work equally well, but those I have to pay retail for and surp860 is a fraction of the cost.) No reason I can see why TU8000 wouldn't work as well. The only downside to them is that there is often some unburned powder left in the barrel, but that just means going through a few more cleaning patches over time. I have found several 100yd subMOA loads in various rifles, and the recoil with these loads is a fraction of that with full charge jacketed loads. Gas checks cost about the same as primers, that's the only cost compared to $.20 - $1+ per jacketed bullet.

Otherwise, you could trade it to someone you know who can use it for something you can use. Depends on where you are how realistic that is I guess. I belong to a shooting club that meets monthly so there is always someone who can use whatever I can't and always a good deal on something I need.