[Weevil]

Bought a M77 Varmit 220 Swift in 75 ,....My first new rifle .....I was 15..... It came with target blocks ,Gunsmith said here are the rings you don't need those. Here I am 37 years later and I am wanting a set so I can mount a Unertl scope to target blocks . Anyone got any Idea what the thickness of the front and rear should be . My barrel is tapped for them.I believe they are 6-48 but not sure .Anyone have a set they would part with,or know how to get a set of factory or specs for them . Looking at Ruger diagrams they are not shown ....Thanks

 

[Weevil]

The factory blocks should accept Lyman or Unertl but not Fecker as they are a little narrower , but Fecker mounts can be used with Unertl or early Lyman . Not POSA but think Lyman had a newer mount later a Posa that has a another cut or could be another micrometer style ring
....Anybody .....Any Clues.....?????