Marlin 60 dovetail... not 3/8" ???

[TheDan]

I've got a Marlin 60 that I've had for awhile, but never scoped it. I decided I was going to do that tonight, but to my surprise the base I had didn't fit right. So I went to Academy and got some .22 rings... they didn't fit either! I measured the dovetail with a caliper and it appears it is 11mm. Are all Model 60s like that or do I have an oddball? Anyone know of a place that might have a 11mm mount or rings in the Austin area?

Below is a picture of the attempt to fit the 3/8" mount:

 

[M. Sage]

I've heard the newer ones are a little on the wide side. Better a little oversize than undersize, IMO. I think they did it because older rifles like mine, the dovetail actually is a little undersize. I've had issues with scopes staying put with cheaper rings.

 

[TheDan]

I understand being a little oversize is better than undersized, but a difference of 1.5mm is quite a lot. I tried just cranking the mount down, but that caused it to tilt to one side slightly. I don't know exactly how old this rifle is but I'm going to guess 10-15years old. The only other Model 60 I have was my dad's. It's much older and already has a scope mounted. I guess I could try the new scope out on it, but I'd rather leave it the way he gave it to me...

I returned the 3/8" rings to Academy this morning. I tried asking if they had any rings for an 11mm base but they didn't understand what the hell I was asking for. Still looking for the correct rings... Most airgun dovetails are 11mm right? Suppose I could always buy a cheap airgun scope and rob the rings off it.

 

[matefrio]

Looks like the gun was machined up top at 4pm on a Friday. You can always remove the excess or shim the scope rings.

 

[TheDan]

Looks like the gun was machined up top at 4pm on a Friday. You can always remove the excess or shim the scope rings.

If you look at the insides you can tell they got lazy with the machining... not that its much better on my 795. The thought did occur to me to try and "fix" it, but I hadn't thought about shimming it. Got plenty of small washers laying around, I might try that. Wouldn't that make the scope slightly offset, tho?

 

[matefrio]

I would try two things,
First, flip the part over that making the part I've circled the bottom wedge. It looks up side down.

If that doesn't work put a shim up top between where I put the yellow circle.

 

[TheDan]

I ended up getting a set of Millett Angle-locs. They are adjustable from both sides. They seem to work pretty good, although I'm not sure how to tell I have the scope perfectly centered. I suppose I could find mechanical zero on the windage of the scope and then adjust the rings. Eventually I think I'll order an 11mm mount from somewhere, but these will do until then.

 

[M. Sage]

Wait... Rings from Academy? You sure the rings were to spec?

I'm pretty sure the dovetail on the Model 60 isn't machined on. Fairly sure it's left as-is after the receiver is die cast.

 

[TheDan]

The first thing I tried was a 3/8" one piece mount I had on hand. When it didn't fit, my first thought was "this POS mount isn't to spec!" That's when I got the rings from Academy. When I found the second set of rings didn't fit, then I suspected something was up with the dovetail. I measured it with calipers and its spot on at 11mm. Maybe this rifle was supposed to goto the European market, or maybe it's just a lemon. Dunno, but that rail is for sure 11mm.

I'm pretty sure they do some finishing work on them after casting. I don't think the surface would be was smooth if they didn't. Also pretty sure they couldn't get those fine grooves on the top of the dovetail by casting. Anyone know someone who works at the Marlin factory that we can ask?