Mounting a Williams Peep Sight on a Sheridan

My uncle called me at the shop a few weeks ago and asked me to stop by on my way home.  Our mutual friend, Sandy, had kindly dropped off two Sheridan rifles for me.  We shoot firearms together and she'd heard about the airgun blog.  They belonged to her late husband, Paul, and she wanted them to go to a fellow shooter. 

Both of the Sheridans are exactly the same vintage with the rocker-type safeties.  Of course, both are .20 caliber and have real walnut stocks.  They've got the dings and dents to show their age.  They were users, not safe queens.  Of course, I'd like to clean them up a bit.  Maybe an oil finish on the walnut, add a recoil pad... Anyway, to that end, I removed the stock and pump handle from one and started to sand off some of the factory varnish in preparation for a higher quality finish.  I need to get into the garage and do some finish sanding, but this morning the thermometer read eleven degrees.  So, I turned to the second gun (in the much warmer basement).



 
No idea of the exact vintage.  1970's?

The scope is great to shoot with, but it covers the exact spot on the receiver one should grasp while pumping the gun.

It's also difficult to lift the bolt and cock the hammer.  The clearances are just tight enough to make this awkward.

Removed the scope

This'll find a home on a different air rifle.

Removed the intermount.

The original sight was also removed.  I've read that these sights can promote solder separation between the barrel and pump tube.

Took the action out of the stock.

Removed the two screws holding the cover and cam plate.

Here's the bolt lug.  It's a 1/8" allen head.

Surprised to find that I have a nut driver that small.

Use care when removing the bolt, as the bolt spring will go flying.

Bought this Williams peep sight from Chuck at Precision Airguns in Maple Heights, OH.

On the new Sheridans, the rifles are factory-drilled for this sight. On the older guns, it's up to you, baby.

The supplied mounting bolts are #6-48.

Did some layout on the breech and gently clamped the action in the milling vise.  Found a piece of brass tubing that was a snug fit in the bolt channel.  Drilling through the breech and into the tube let all the chips drop into the center of the tube rather than into the pump/valve mechanism.  Also prevented any burrs in the bolt hole.

Drilled with a #32 bit.

I actually have a #6-48 plug tap???  This was an even bigger surprise than finding that nut driver.

Installed the sight and put the bolt mechanism back together.

Took few sighters and had the gun zeroed in a dozen or so shots.  The double screws holding the sliding windage adjustment is rather crude, but the gun is substantially easier to pump and work the bolt handle.  A good trade off between precision and ease of use.  The trigger, by the way, is exceptional.