I put new scopes on my FAL and G3 in the last year, and took both of them to the range today to sight them in for the first time. I started with the G3, and it went smoothly. My G3 is actually an early PTR-91 (polygonal barrel, plain muzzle) made up as a "poor man's PSG-1" with a Magpul adjustable stock, wide G3 forearm with bipod, Bill Springfield match trigger, etc. I put an original HK claw mount and Hensoldt scope on it. It was on paper at 100 yards from the first shot. I used Portuguese milsurp for the first 10 or so shots, and once it was close, used 10 rounds of Federal 168 OTM Gold Medal Match to zero it. The last three shots were a nice 1" cluster around the aiming point. I then put the G3 away and pulled out my FAL. It's a DSA SA58 para carbine, with a 16.25" barrel and Belgian short flash hider. Last fall, I bought an IOR Valdada 1-4x tactical scope and rings from DSA and had my gunsmith mount them. Again, this way my first trip to the range with it since the scope was mounted. My problem is that I couldn't seem to get it to group consistently and I don't know why. When I started, it wasn't on the paper at all (my gunsmith had warned me that he hadn't been able to boresight it because his boresighter wouldn't work with the flash hider). I finally figured out that it was shooting about 15" left and 8" low at 100 yards. I dialed in a ton of windage in several steps and seemed to get that fixed, and then started working on the elevation. No matter how hard I tried, however, I couldn't get two shots to go anywhere near the same place! Even when I switch from the milsurp to the Federal GMM, I would put one shot two inches high and left, and the next would go 1 inch right and 3 inches high. The next one would be one inch left and four inches low. I was shooting about a 10" box around the bull! FWIW, I was shooting off sandbags on a bench. Conditions were warm and humid (about 76 degrees), with a very light, variable breeze -- not enough to cause the shot variation I was seeing. The ammo I used in the G3 and the FAL came from the very same boxes. Help!