Scope mount frustration, help needed

[bikemutt]

I have a Cooper rifle with Leupold two-piece bases installed. I have the correct Leupold STD rings for it.

The problem as I see it is there is nothing flat on this rifle I can use to know when it's sitting level. The closest I think I could come is to remove the scope and rings, secure the rifle's barrel in a barrel vise and put a level on the front base. The front scope base isn't a wide span but maybe it would be enough. Then at least I'd know the rifle action was level.

Is there an easier way? Am I over-thinking this?

Thanks

 

[hoghunting]

Is there a flat on the bottom of the action? I have removed the stock on a few rifles because of the same problem you are having, and found a flat area on the bottom of the action to place a level.

 

[rcmodel]

Not up on my Coopers, because I can't afford them.

But shouldn't the bottom of the mag box with the floor-plate open be pretty square with the action??

At least it should be if it has a floor-plate??

rc

 

[bikemutt]

This rifle does have a floor plate, it's a model 57 in .17hmr.

I'll check that out, as well as hoghunting's suggestion to remove the stock and look for a flat spot there.

Thanks

 

[sage5907]

If you are using a Leupold STD mount the easiest way I have found to mount a scope is to turn the front ring into the base by twisting it clockwise with a piece of large dowell stick. Then place the rear ring in the base so it is centered and the left large screw is where you want it to be when the final tightening happens. The right large screw head should be loosely tightened so it can move when you place the scope in the rings. The idea is to keep the ring firmly against the base but to let it move so it won't put a bind on the scope. When you position the scope and set the eye relief the easiest way for me to position the vertical crosshair is to set the tip of the barrel on the floor and look through the scope with the scope about a foot away from the eye. The vertical crosshair should be pointing down toward the center of the bolt. Once the scope is positioned all the screws are tightened with the large right screw being the last one in the sequence. On new rifles like the Cooper where the receiver is CNC machined from a block of steel the rear ring should easily center in the base when the vertical crosshair points to the center of the bolt. Your experience with shooting a rifle should tell you when the scope feels wrong. On older rifles where is receiver was heat treated after it is machined the rear ring may not be actually centered when the scope is mounted correctly. This problem can be identified by holding the rifle horizontally and looking down on the scope to make sure the objective bell is in the center of the barrel. This is the big advantage of using the STD bases and rings.