Tasco ?

[98dodge]

I have got a tasco 1-3.5x20mm from 1989 someone gave me and I am trying to figure out what size caliber would be the biggest for this scope any info would help thank you all very much.

[SongDoghunter]

I would imagine that a .22 would be about the best fit for that scope. If it has smaller than a 1 inch tube, the rings would be designed to clamp onto a .22 receiver groove.

[buckhunter]

or a pellet rifle.

[fmrleatherneck]

Sounds more like an air or co2 gun than even a .22. Long eye relief would mean a pistol scope.

(...and 20mm is just less than 1". 1" = 25.4mm)