Model 37 deerslayer. 40 ish yrs old. Time for a good cleaning and I can't get the Magazine yoke off.
( pretty sure that's what it is) Screw is stuck. Already marred the screw a bit but plenty of stock left to get a bite on it. So I am using some WD for a night to see if that helps. It's not rusty.
Any ideas or help much appreciated.

The best stuff to use is PB Blaster. The stuff will work better than the WD 40. Also some heat from a hair drier will help.

Thanks. Gave some thought today to use a heat gun I have. Soaking in WD didn't do a thing.
After that itsn going to the smith. There's a reason people get paid for such things.

Had a similar problem with a 1941 20 gauge.Took a flat nosed punch that fit the screw head and gave it a couple of raps with a hammer.Came right out.Hope this helps. Retiredreb

I see this is an older post, but new member here that just got finished dealing with the same issue.

My 37 was inherited, its from the late 40's and was neglected, left in storage. Rust was pretty substantial.

I ended up taking a dremel cutting disc, and putting it between that gap on the yoke, and severing the screw. A bit extreme, but the screw head was already destroyed. Replacement yoke screw and assembly runs under $10 from Ithaca.

Not a bad way of getting the screw out. Sometimes they are just two far gone.