R3 issims. I also tried one of these thinking I'd get a better fit but no luck.

As to the process for a smith and a grind to fit. They'll sell you the pad and you for fitting. I have installed a few grind to fit myself and the process i use is remove the stock from the action/barrel, then install the grind to fit onto the rifle, put 2 wraps of masking tape around the heel of the butt and grind it down using a bench sander until the first layer of masking tape is removed. I then finish fit it by hand. With the sims I freeze the pad before grinding, works much better as the resin used is soft. Pachmyar I haven't.