I decided to try the Limbsaver X-ring deresonator, and got varied results. Was wondering what the results were from some other users. I bought the small size, for use on my FN FAL. It also fit on my CZ 452 in .22LR, and I decided to try it first on that rifle, as it is very accurate with certain ammo. I put the X-ring on the suggested spot of the barrel, and groups opened from 1" to 3"-4" at 100 yards using Stinger, my preferred prairie dog round. Since that test proved I was better off without it on an already accurate rifle, it was time to test it on the rifle I bought it for, my FN FAL. I had installed the Stg 58 bipod on my rifle barrel, and I was warned by DSA that my groups would probably increase. They did, but I had managed to get them down to 1.5" at 100 yards with a custom handload using Ballistic tips, which translates to 3.0" at 200 yards. I installed the X-ring deresonator in the suggested barrel location just ahead of the gas block, up against the bipod clamp. An average of 5 different 5-shot groups gave me 1.8" at 200 yards, or about 0.9 MOA. Not bad for a basically stock FN FAL and typical windy Montana day. I did a quick 5-shot group at 100 yards and got about 1.1", from a barrel that was by now getting very dirty. No cleaning occurred during the 30-shot firing string. Groups had been slowly opening at the 200 yard distance. The first 200 yard group was 0.65", and that is for 5 shots. This is my conclusion: try the X-ring deresonator on a rifle that is shooting a bit lousy, if you try it on an already accurate rifle, it's more likely to open up your groups, and it will look funky on a sporter rifle. On the FN FAL, the X-ring deresonator looks cool as if it were made for the rifle, and I would have it on my rifle just for custom looks as long as it didn't affect the shot grouping. That it reduced my groups very significantly means it is a permanent fixture on that rifle. The retail cost is $20 or so, but I found mine at Fort Thompson in North Little Rock, Arkansas, for $10. They sell a lot of them, and the salesman said their customers reported consistently good results. He admitted it sounded like snake oil to him, but they keep stocking them and people keep buying them. If you need a bunch of them, I would look up Fort Thompson, they have a website, and you can save major coin over the $18 Cabelas price. Oh yeah, when you lube the thing to slide it into place, let it sit overnight and the oil will be absorbed into the material and it will stay put under recoil as if it were welded to the barrel. Do all your tuning before letting the thing stay in one place for long, or you will have to squirt oil underneath it to get it to slide again.