Lyman 48 sight repair

[Mustang]

Anyone have a source for Lyman 48 sight repairs?

I bought a Swedish target rifle that has a l
Lyman 48M sight on it. Elevation knob turns, but doesn't raise the sight.

[RHT447]

I'm no expert, but some of those sights have a "locking bolt" for the elevation threads. This "bolt" (actually a third knob you unscrew) can disengage the threads so you can simply push the sight back down to zero instead of having to crank the elevation knob. Maybe the "locking bolt" is stuck in the disengaged position? Try pulling up on the sight and see if it moves.

[Mustang]

Thanks, RHT.

I unscrewed the elevation lock, but the arm seems frozen. It will not move up or down

[Hamsterbear]

Thanks, RHT.

I unscrewed the elevation lock, but the arm seems frozen. It will not move up or down

Kroil it.

[RHT447]

Kroil it.

+1 on Kroil. A trip through a sonic cleaner might not be a bad idea either. Once it comes loose, separate the arm from the base. Once done in the cleaner, blow dry with canned air. Saturate with WD-40 and blow dry again. (For those who don't know, the WD stands for Water Displacement. The 40 is for experimental recipe #40. The first 39 attempts didn't work). Apply a few drops of your favorite gun oil and re-assemble. Should be GTG. Good luck.

[ojisan]

It's got a wedge-shaped screw in it that the nut goes on.
It is probably rusted in place.
Use some Kroil or Liquid Wrench on it first.
Then loosen the elevation lock nut a couple turns and then, using a small hammer, give the end of the nut a gentle rap with a piece of wood nylon drift punch or similar on the nut head.