Steve;
When you build this rifle, put the front sling
mount far out on the barrel and get it away from your
hand. Mine is mounted just in front of the forend wood
and if you are not carefull, it will slide across your
hand under recoil and cut you up.
Limbsaver recoil pad works nice. Decelerator also is
fine. Had both on mine and can't really tell the
difference.
Your could always put a standing rear with one folding
sight, file the standing for your 650 load and use the
folder for the 750. Just a thought. I have only a standing
sight on mine, it works fine for either load. This is not
a long range target rifle. Both loads shoot pretty clost
together at 50 yards or so.
Good luck with your new project. Sounds like fun
Raff