Me again. Next evolution. I will try to address as many of the comments as I can. Cast bullets, barrel/action vise, etc.

Cast bullets are an obvious go to, but cast bullet shoot best out of a s-m-o-o-t-h barrel and this one ain;t. So, today I cast up a bunch of bullets out of pure lead with the intention of firelapping the barrel. I know this is a controversial technique, but I have done so on different project with good results. The first hurdle was how to get bullets big enough to lap, well, anything in this .316 barrel. Sooooo, I smooshed them in my vice until the .310 bullets fattened up to .317. It was surprisingly easy to get them consistent by watching the position of the vice handle. I used LBT fire lap goo, which is extremely fine, maybe 2000 grit. rolled the bulelts between two plates and loaded in the case in front of 2.5 grains of IMR 7625. The goal with firelapping is to move the bullets as slowly as possible and still exit the bore. fired 20. the bore seems to be shinier and smoother. Whether it is smooth enough, time will tell.

A couple of places appear to offer cast bullets up to .314-.315. I am tempted to try a few, but logic suggests they should be at least .3165 to shoot well from this barrel. Another idea would be to paper patch a generic .308 bullet up to .316. .308 bullets are everywhere, and I have lots of paper, and obviously way too much time.

Barrel and action vise. - The receiver "vise" was made out of soft"1 pine boards routed out to fit the profile of the receiver. These promptly cracked until I epoxied a could of layers of plywood on the back. So, soft pine to face the receiver and plywood for strength. The barrel "vise" was made out of two hunks of hedgwood (locust). The is the biological equivalent of iron. There are two blocks with a hold down the center.
The receiver side has a 7/8 hole and the other side 3/4. The four corners have 5/16 all thread with huge washers and nuts on both side. The idea is to sandwhich the receiver in the vise and the barrel between the two locust block and turn. I failed to get enough leverage so I epoxied a 5 ft 2x4 onto one of the locust blocks. Then it wanted to turn on the barrel, so I glues some .220 emery cloth into the cavity of the blocks.
Voila, that increased the purchase on the barrel enough. The barrel came off and nothing broke. Pure Rube Goldberg engineering, but the price was right and it worked.

I believe the next effort to get some accuracy will be to try the patched bullet idea and to lay in a supply of the cast bullet as close to .3165 as I can find. Frankly I am not expecting much because both patched and cast bullets want a smooth barrel. But what the heck. We'll let the testing tell the tale. More as it happens. Dan