I am very new to this hence why I am asking.
I actually just ordered a 3" Flat, Benchrest Forend Adapter from Sinclair. I was actually considering having a second stock made up and pillar bedded for my 40X 100 Yard Gun and doing a Change Stock thing like a Change Barrel gun, until I found out about these adapters.
I am planning on shooting my first match at Cherry Ridge on the 23rd to get a little experience. Bob White told me that my Remington Factory 40X with the FACTORY stock will qualify for the mornings FACTORY Class. I would use my curved front rest bag. Any Scope is OK too. For the afternoon Heavy Varmint, looks like I can make weight with the Sinclair adapter which attached at the front sling swivel screw and will provide better stability in the rest with my Benchrest Front bag.
In looking around it looks like Evolution Gun Woks and Whidden makes a product like this as well as Hart.
Maybe these are just this groups rules, but my understanding is that at least for this match / group, the Factory rifle has to be factory stock. Not sure about trigger.
Bob