The 1.25-4x Accupoint has a huge eye relief, more like 6" or 7" than 5".
Good for fast shooting but causes mounting problems. But it's a great scope.
The 3-9x model has a much shorter eye relief or so I've been told.
I tried the 1.25-4x on top of my AK (with duct tape - just to find the position with correct eye relief) IMO it should be mounted with turrets directly above the rear sight)
Take a look at this 1913 rail:
If the rail had 10 grooves right up to the place where rear sight meets the gas tube then
TR21 would fit just fine in 2 rings.
It's such a perfet fit, I decided to pursue is as a project in around Jul-Aug 2006