Vanilla Gorilla and Bullet - I agree, shooting the PTR-91 is a bust in the chops.
Recoil in the shoulder wouldn't be so bad, but that smack in the face you get when the bolt carrier slams into the back of the reciever is no fun at all!
Any ideas how to control that? Stronger recoil spring? Polyurethane buffer pad? different stock?
I'm planning on converting mine into a SR-9 TC - the poor man's PSG-1
I already purchased a 24-inch heavy barrel for it, I need to get a PSG-1 trigger group - or williams set trigger, and I need the PSG-1 buttstock. the SR-9 TC used a wierd forearm that I don't really care for. I'll probably be putting a standard HK-91 wide forearm stock on mine - just like Billy Zane's rifle in the movie "Sniper."
Brugger and Thomet also makes a 3-rail ventilated aluminum HK-91 stock which merits some attention. I have seen pictures of it, but not of one mounted on a rifle. I like the thought of having 3-rails though, easy to mount bipods and other rubbish.