A client brought me his pet Urika 20 ga, would not spit the empty hull out of the port. I gave it a good cleaning including full detail strip of the recoil spring & tube. Re-lubed, assembled and it ran 100+ rounds flawlessly. Over the years he had run in excess of 10,000 rounds through the gun without changing the spring, so I said let's replace it. He agreed, I replaced the spring with what I was assured was a new factory spring, wich I measured at just an inch plus longer than the old spring. No worries, those springs do shorten with use. The gun would not eject the spent hull. I called MGW (where I got the spring), Cole and Brownell's trying to find the specs on the spring (coils/inch, wire diameter, spring constant and relaxed length). All agreed the 17 1/8" for the new spring was correct but no one had a clue as to the spring constant or the other specs. I used my Trigger Scan to measure both springs, the old was 2 lbs and the new spring was a bit above 3 lbs. I reinstalled the old spring and am awaiting a range report now. Anybody got any info on what these springs should measure? I was told (by two of the vendors) that they install these all the time and they work "just fine".