I picked up an old ML a few years ago and am now wanting to do something with it. It is a 50 cal. underhammer that uses the trigger guard for the hammer spring. This old relic has no markings on it except for a very small 509 stamped on top of the 26" octagonal barrel. It is in remarkably good condition except for the bore. I have tried eveything under the sun to get it shootable but it is corroded so bad I have given up. I want to shoot this gun so bad it's eating me up. Should I try to find a liner and reline it or see if I can get it rebored to a 54? It's a fine looking old rifle with a beautiful walnut buttstock/splinter forearm and the patina is a nice slick as glass shiny grey. I've disassembled/cleaned and reassembled it. Everything looks fine and functional. I really want to put this gun back into service. I've researched underhammers and all I can come up with is the fact that in the mid to late 1800's there were 1000's of these types of rifles churned out in the New England area w/o markings. I'm willing to do what it takes to get this rifle shootable. I'm getting bored with my inlines. Thanks for any suggestions, Buddy.