filler material for scope base

[Zip]

What can be used to fill any cavities between a scope base and firearm mounting surface. (anodized base/SS frame)

It has to be something hard when cured, can be worked before it sets and later allow the base to be removed if necessary

Thanks

 

[Pete Deal]

I use epoxy.

 

[Kurt Learning]

Brownell's Acraglass is always on my work bench.

 

[Zip]

May as found what I need by luck...looking through my parts bins I found some JB Weld PlasticWeld.....20 minute work time, gets hard and won't shrink. Testing it on some parts right now. Plan on lubing the parts so it won't stick properly then roll the material into small balls and place them between the screw holes. Then snug the base down and wait until the next day to make a final torque on the screws.

Learned that even with factory scope bases on S&W revolvers with the three 6-48 mounting hole the scope base actually bows when torqued down.

 

[Zip]

Ultimately, everything moves at least a LITTLE bit.

But JB has fillers in it. More filler than binders, AFAIK. It could end up raising your mount off the host metal if you wait that extra day? Lord chemical is even more that way. They compound their goop with precisely sized glass balls to control final seam minimums to suit various choices for industrial bonding, auto industry and not-only.

I'd ha' thunk that before epoxy even existed, (it's younger than I am in general use..) a shellac or varnish would be all that was needed to exclude moisture and dirt from what should be a very close fit, that type of mount?

Before "Permatex", now "Loctite" gobbled-up so much of the market, "Indian head" red shellac gasket liquid might have served? Alcohol cleanup, 'round the edges. Heat releases shellac, too - and not a lot of it. Wouldn't even know it was there.

Good info..Thanks

 

[Scottl]

As for a scope base bowing when torqued the correct solution is to correct the base to match the revolver. This can be done by judicious sanding alternating with checking the contact with some media, even lipstick if nothing else is available. If you don't want to do that then make shims for areas with gaps.

On rifles meant for long range accuracy the rings are usually lapped using a 1" rod to correct misalignment before installing the scope.

I agree with thermite about shellac being a better material. It is even available in sticks (dopping wax) that can be melted into place and later completely removed with heat and alcohol. Jewelers use it to hold gems for grinding and guys who build muzzle loaders often use it to fixture parts like tumbler castings for initial machining.

 

[Zip]

Didn't want to detail my project...but I made a two piece "revolver" scope base. The lower portion mounts to the revolver's factory drilled/tapped topstrap. The upper half mates to the lower half, holds the red dot scope and pivots from a center point. This allows the scope point of impact to change while shooting a moving (7 MPH) target...once calibrated there is no need to lead the target...just adjust the base R/L and aim center mass in either direction.

My problem was after attaching the lower base no matter what sequence I followed torquing the (3) screws I always wind up with a "very (very) slight" air gap between the two mating surfaces. This could affect the pivot tension.

Yesterday I drilled holes (3) in the top piece...so I can firmly secure the top/bottom pieces together as a complete unit and ensure a flat mating surface.before attaching the entire unit to the revolver,. This is where I figure a filler would help, put in a couple small balls of the filler, torque the base down to about 90%, let the filler harden over night...then complete the final torque.

 

[Zip]

As for a scope base bowing when torqued the correct solution is to correct the base to match the revolver. This can be done by judicious sanding alternating with checking the contact with some media, even lipstick if nothing else is available. If you don't want to do that then make shims for areas with gaps.


Trust me...I have been attempting that....even factory made mounts do not truly lay flat. BTW My mount is aluminum.

 

[Zip]

Aye, but you DO seem to have a fairly unusual situation, and on more than just the one metric!

Because the zero mechanism was built into the mount, some Balvar 8 (rifle) mounts (Kuharsky Brothers, Maynard P Buehler, et al) were right STOUT contrivances. Might bend the wheel-gun's top-strap before the mount moved.

No, that it is not germane, but..

IF.. I were to mount a scope on my choice of handguns, it would be attached to a grip. The slide of a semi-auto is not exactly "kind" to them. Not happening, as I don't care to take a shot at a(ny)distance beyond open-sights range.

Out of ignorance, then, is even a "mild" round wheel gun so much more "gentle" that this system is stable, filler or not?

I'm only shooting 50 yards!.....the only strain on the top strap is the (3) mounting screws...side to side strain is between the two bases.