Bringing an 1885 Winchester back to life

[proud American]

I just bought an olser 1885 Winchester Lo-Wall that I want to bring back to life. I was built in 1890. Mechanically all is good. The wood is very salvageable. The problem is it came from the factory chambered in .25RF. What do I do with the bore and chamber? I'm thinking maybe reline for .22 WMR and was wondering if the firing pin will strike the cartridge properly, or will something have to be done to it or rhe breach block? I realize that the extractor will also have to be dealt with.
The finish on the metal is pretty much gone, but there is no pitting. I also plan to turn down the octagon barrel at the muzzle end so that I end up with a 1/2-rnd-/2-oct barrel. I can't afford a Malcomb scope so I'll probably use a tang peep and a Beech Cumbination front sight, but that's down the road.
Your thoughts will be greatly as I begin to lay out the plan of attack on this new project.

 

[Jonnyofalltrades]

Are you doing the work yourself?
Firing pin location on a falling block single shot has a lot to do with the condition of the pivot pins. Worn pins equals a lower strike.
The rims are only .033" different in diameter. You might luck out...

 

[clowdis]

That's a tough pin to relocate and I don't know if it would hit the .22 rim in the proper place as is. You could get a replacement falling block from Wyoming Armory if it isn't cost prohibitive. http://www.wyomingarmory.com/gun-parts.html

 

[AR Shooter]

Talk to C. Sharps Arms and/or Montana Vintage Arms about getting a proper firing pin. They both make reproduction 1885 models and they may have a firing pin that will work with little or no modification. Also look at DZ Arms. DanZ used to make 1885 parts and may have what you need.
Surprisingly, eBay can be an excellent source for parts on old rifles. You never know what you'll find there.
There are a number of excellent gunsmiths out there that specialize in the single-shot falling block rifles like the 1885 if you want to put the $$ into it. Excellent rifles when done well and you can have a standard trigger, single-set trigger, double-set triggers (including close-coupled DST). Can be made into a beautiful rifle worth several $thousand if you wish.
It is an appropriate rifle for the 22BPCR game, which has become quite popular with the nationals being held at Raton every year.