I bought a box of A5 parts today. It had a bunch of various parts, from original 2nd and 3rd generation butt plates to a couple of early magazine caps. A whole bunch of screws, small parts, etc. Anyway........included is a healthy handful of recoil springs. All are in a bag with "new" written on the bag. I could pick out the 12 gauge ones as those all measured 9 1/8"--9 1/4"( or so). There was another healthy handful of springs which a bit more variation in length (up to 5/16" difference), and a smaller diameter. I am guessing 16/20 gauge. Can anyone tell me what the "new" length is supposed to be for a 16/20 gauge spring? And, I guess I got ahead of myself----is a 16 and a 20 gauge spring the same spring? I see them sold under the same listings, so I guessed they are one in the same.