The leaf springs are def. dif. between the 12's & 20's and will not interchange. On the 28's, there were some 'small frame' guns made. Easiest way to tell if yours is one, is to measure the distance between the firing pin holes in the standing breech's face. It's ¾" on those guns. I wanna say that the leaf springs are interchangeable on the regular 20's, 28's and .410's but as Russ used to say, 'I could be wrong'. I honestly don't know about those small-framed guns as I've never suffered a spring failure on the one that I have. I'm going by memory here and it's been a long while since I've had to replace a spring in a 12 or 20. I bought one set ea. to have as spares many years ago and a tool to aide in doing so when they were still available after I experienced the first failure. And, FWIW, unless yours are broken, I would continue to use them until one does break. I've one 20 ga. Empire Grade Daly/Miroku that I had oversized firing pins made for, and the disc holes rebored after they had worn too oval to be fitted with std. replacement pins again. It was due to the pins dragging when opening the gun, not breakage; they do wear from rubbing against the disc holes & bottom one is the worst. That was the 3rd set; it seemed the more expedient and best way to remedy that particular wear problem. Broke an ejector on that same gun in S. America and had it welded back together and dressed and properly annealed afterwards 20+ years ago and it's still going strong, though I don't shoot it as much as I once did. Still, it has probably 6~7 K rounds through it since that repair. I'm thinking that Weisner's (sp?) may have a schematic online for those guns but again, could be wrong.
Hope that your restoration goes well for you! They are well made fun guns from that period. There are also some variations in the ejectors and grip styles utilized as they evolved.
Last edited by tw; 10/19/24 03:52 PM. Reason: clarity