Rimfire Central has an Appleseed section, and there they've been talking up the TacSol cantilevered scope mount for rimfire rifles. So I bought one.
Every other cantilevered scope mount, that I have ever seen, holds the scope up pretty high. Average is at least an inch from the bottom of the scope tube to the rail. For most scopes, that people are going to bring to Appleseed, 3/8" is plenty to get adequate clearance. The TacSol is 7/16". The bottom surface of the cantilevered part is shaved about 1/16", so it looks like they could have made it 3/8" without sacrificing strength and integrity. Regardless 7/16" is a big improvement over everything else out there.
It is made for "rimfire" rifles. I don't know why it wouldn't work on high power rifles, so I was going to put it on a 7mm mag, but was practicing today for next month's Appleseed. Even though I have a cantilevered picatinny rail, my scope needed to move farther forward. So, I put the TacSol on and went outside to dial it in.
Accuracy did not suffer.
Now if TacSol will just make them in 30 mm and 34 mm.