For a front swivel, I use a wider tenon just for the swivel screw. The wide tenon keeps the screw from being twisted in the stock, maybe splitting the for end. The swivel tenon is placed so that when the swivel drops while loading, it falls
on a thimble, not blocking the thimble. In the woods, with that urgent second shot, you might just need to easily and quickly replace the rr without having to fidget with the swivel.