Home Forums Hunting & Shooting Ask The Gunwriters Lappin' Rings....worth it?

Hey, here's a quick and dirty for yah, works for Weaver type mounting systems.
You can get a STRAIGHT hunk of 1 inch bar stock (or 30 mm) from a good metal supply house, or turn your own in your trusty lathe. A foot or so should be enough.
Go buy a pack of KS brass shim stock and some JB Weld or other decent stiff epoxy.
Get some mold-release compound, which you already have for bedding your custom rifles.
Have a good straightedge handy.
Securely mount your rifle in a vise or work stand, sunny side up.
Install your bases. If they are Weavers or Picatinny type, check your alignment. If you see daylight, you can slip the brass shim stock under the bases in the right spots, to get close.
Attach the ring bottoms.
Set your bar in the ring bottoms. Take the shim stock and see if you can poke it in any gaps at the sides or bottom. Take note of there the gaps are, and how big. If you found gaps, then cut yourself little hunks of the .005 brass, about the size of your pinky nail, slip those under the bar. This will raise the bar a bit. Put some shim material, an amount about equal to the gap you found, where the gaps were. You want to just fill that gap for positioning purposes for the next step.
Take note of where your shims/gaps are. Set them where they are handy.
Liberally coat your bar with mold release, let dry.
Mix up enough epoxy to cover the mating surfaces of the ring bottoms.
Spray some release agent on your finger and swipe the mating surface in the rings. This way, it won't slip later but can still be chipped out. Or if you want to be permanent, forget the release agent in the rings.
But you dang sure better put it on the bar.
Put a thin coat of JB in the rings, then put the hunks of brass where they belong, add enough JB around them so you think it will fill or mostly fill around the shims. Try to have it so the brass will "skin" with very little epoxy on top.
Lay in the bar, carefully, well-centered lengthwise. Work it only enough that it seats well, let gravity do the rest. Carefully wipe off any excess, especially above the centerline that might lock the bar in place. AND DON'T SLOP ANY EPOXY IN THE CLAMPING SCREW HOLES. THAT IS A BAD THING TO DO.
Let the JB cure, then pull the bar, trim off any brass sticking above the top line of the lower ring halves, slap in the scope, and go shoot.
I've done this several times, once to get a big scope above the highest rings I could get. I had to get longer clamping screws, but that gun shoots like a champ. Ugly but fast and effective.
I've also done this to try out a different scope or rings setup without going through the lapping rigmarole. Again, as long as you use good mold release and common sense, it works just fine, and you can always chip the JB out and lap the rings for real.

I've lapped in rings one time, and it worked very well, but I haven't seen anyone mention the way I did it. To put a set of dual-dovetail rings on a 700 I lined them up best I could with a set of pointy bars. Then I put the lapping rod and compound in and gave about three strokes and took them out and cleaned the rings. This bit of lapping showed a slight miss alignment that I corrected by turning the lower ring. I repeated this lapping and cleaning process two more times till no miss alignment showed, and then installed the scope. After two shots at 25yds, and a three shot group at 100 it was sighted in.

I always wonder if the $20 tool is staright enough to give accurate information about the action/rings . . . . .

BMT

After you lapp, the scope tube should slide through the lower rings. That proves there is no binding. What is noticeable, is how smooth the slide is compared to trying that without lapping.

AGW

Thinkin' here that gaining maximum good alignment of rings before any lapping is done, is a given...

Kinda along the same lines as getting the screws tight first also.........