went into a gun store(didn't make the range) seen a mk-85 the one I drolled over 20 years ago, or so. ss with the fancy stock looked good on the outside except broken rear williams sight...so i asked how much? they don't even know lol they say make me a offer so i say I'll give ya a 100....they look at each other and sure why not lol...I should have said 75...they said they don't sell and don't want them only pay cheap money and sell them cheap...the other 2 mls were cva one was trashed and the other fair/good....now I got to figger how to take it apart to look at the bore can't be too hard I'm thinking it comes apart some what like a black diamond...the plunger works safty too # 11 nipple...I bought 12 cans if musket caps (1200) for 38 bucks(tax included) so far its a good day

Just loosen up the set screw on the left rear side of the reciever and you should be able to loosen the end cap and pull the plunger right out. Pull the trigger back at the same time. I wouldn't be surprised if that breech plug is stuck the way things look so you might want to get some good penetrating oil in their and get it soaking. If you don't have a breech plug tool you will have to get one or make one that will work.
I don't like the looks of that breech area too much, I hope the bore is better.

Definitely a beauty on the outside. Even if the bore is rusted and pitted that stock is worth $100. Nice snag. I would not have passed on it either!

That stock looks like new too.

Looks like a real good buy to me. I would not have passed on it.

That breech doesn't look all that bad to me. The camera really shows up trace rust spots, even those not visible to the naked eye. But I agree with Flounder, get some penetrating oil working for a few days before you even try pulling the plug.

Unless the bore is really trashed it will likely shoot fine. A Remington 700ML I bought last year ended up with light pitting the full length of the bore after I cleaned it up, but shot nice tight groups.

thanks i see the set screw...I've ran some patches w/ hoppes 8 and then some oil they were brown...some one must have payed good money for this...I'm hopeing it sat and dried out and got alittle surface rush on the bore....going to spray some oil down the bore........what did these guns go for new? 450.00? I couldn't aford it so I got a white mountian for 235 I think in the 80's

That was a super deal. I have no idea why those rifles do not hold their value. IMO they are one of the best rifles ever made. I have one that looks exactly like that one. If you need any parts let me know. I might have some extra parts for that rifle.

Take out the one screw in the bottom of the stock and the action wil come out of the stock. The trigger has only one screw also. Take that screw out and the trigger mechanism will separate from the barreled action.

The trigger probably needs a good cleaning also. Take a can of brake cleaner or electrical box cleaner. Spray the dickens out of the trigger. You can not spray too much on the trigger. Then take your air hose and spray the heck out of the trigger. A little left over cleaner will not hurt, it will evaporate. But make sure you get all the "gunk" cleaned out of the triger.

Don't fret a little rust and pitting in that rifle. It will still shoot well with those problems.

Is it #11 ignition?? Or musket cap ignition?? I have a musket cap ignition for that rifle. You need a separate plunger to use the musket cap ignition. I have the musket cap ignition on my MK-85's. It is a better system.

The trigger is worth more than you paid for the rifle. I know, I have paid more than $100 for a Trigger for the MK-85. You got a winner there. Tom.

some people have all the luck

Nice looking rifle.