Help?- advice? - side mounted scope base for Moss #42 series

[JBMauser]

My friend has asked me to help him mount a scope on his old model 42M Mossberg.  I think this is the same as the 42 with a Mannlicher style stock.  He tells me there are tapped screws on the side of the action.

"There are two sets of threaded holes on the left side of the receiver.
Mid-way, there is a set of very short screws 1 7/8" apart that don't appear
to bear on anything; nor could they appear to be able to hold anything
attached there.  At the near/inboard end of the receiver, there two threaded
holes (no screws) 5/8" apart.  The latter two are of larger diameter than
the others."

I don't have the rifle in my posession to inspect.  I remember that there used to be a side mount scope mount that you could drill out and mount on the side of a rifle.  I think we used it on an MK2 Enfield.  

I would hate to advise him to drill and tap the action and put the two piece #12 and #13 Weaver mounts on the rifle if the side screws can be used.  I know this is not a high dollar gun but still....

Any of you have one?  Any advice?  thanks, JB

[jh45gun]

I am sure there is a factory mount for it or a old after market mount as My 15th edition shows a 42 B with a scope mounted with a side mount. My Numerich Catalog shows them having a scope base for a Mossberg 42 in a side mount.  (Weaver) You could go on line or call them and see. 877-486-7278 Toll Free number for the US and Canada. Chances are most of these mounts were for the 3/4 inch 22 scopes of the era and the el cheapos  3/4 22 scopes of today.

[armory414]

The original side-mount scope bases for the Mossberg were indeed for the 3/4 inch scopes.  The Weaver side mount from Numrich will allow you to use standard weaver rings for 1 inch scopes.