I have a 1953 model 336 SC Marlin in .35 Remington. Best groups so far, with the 200 grain Remington corelokt in both factory loads and Reloader 7 handloads using 3 different primers, is 2 1/2 to 3 inches. Some groups are larger, to 4 and even 5 inches. All groups were fired from sandbags on a fixed bench at 100 yards. Two different scopes have been tried, set on 7x and 8x, in sturdy, tight mounts. I haven't owned the gun that long so don't know how much better, if any, it might shoot. I've cleaned the barrel thoroughly and it looks pretty good inside and at the muzzle. My two other lever actions shoot much better. I know I should try another powder (probably IMR 3031) and maybe another bullet, but Re 7 and the Rem 200 are proven components. I have the feeling that something on this rifle needs to be "tweaked". Any suggestions? Thanks.