Steve here... i'm troubled. I have a no dash 686, I bought a b-square no drill mount. I mounted a vintage M8 4x leupold on it, and with 5 grns of unique under 20-1 H&G 73's I shot two one inch groups at 25yds. Then it went to 4inches.... The lone front screw couldn't take the beating, it was wobbled and stretched when I took it out. I really don't want to drill holes in the strap. Any other no drill options, before I buy a Weigand and put three 6-48's in the top strap...
Thanks
Steven

Aimtech makes a mount that attaches by straddling the top strap and is secured using the yoke screw and the sideplate screw behind the trigger guard. Downside to this mount is that it will leave marks on the sideplate and the sides of the top strap. I purchased a 617 no dash equipped with this mount and it took about 4 hours of wet sanding to clean it up. BTW, that 617 has now been drilled and tapped.

You could try the Weaver 307 No-drill mount. I had one mounted on a Model 27 for a while and it worked fine.

Weaver Mount Scope Base with 1" Rings S&W K, L Frame #307S Silver - MidwayUSA