December 31st, 2009

Kokopelli Ring Lapping Tool and Scope Alignment Bars

If you use mass-production ring sets, other than Burris Signature Rings or SAKO Optilock Rings (which both feature polymer inserts), you can benefit from lapping your scope rings. Lapping your rings, when done properly, with the right tools, can improve the fit of the rings, reducing bending forces and stress on the scope. Properly-lapped rings are also less likely to leave prominent marks on your scope tubes.

Forum member Boyd Allen is a strong advocate of ring lapping for factory-produced ring sets. He’s tried various lapping tools and he believes that the Kokopelli system is one of the best available. Custom crafted in Kalispell, Montana by John Werre, the Kokopelli lapping system combines a specially-machined lapping rod with patented flat-ended scope alignment bars.

Kokopelli Lapping Tool
John Werre, Kokopelli’s owner, explains why his lapping tool works better than most others: “No one was making a lapping bar that would lap anything more than the bottom half of the rings and they were made of rolled stock and only a very short stroke was possible, rapidly wearing out the bar due to the limited area of use. I did something entirely different. I designed the bar to be used with the top halves of the rings in place and utilizing a long stroke thereby distributing the wear over the entire 12″ length of the bar. Why just do half a job?”

Kokopelli Ring Lapping Tool

John adds: “Another problem was that the lapping compound would readily scrape off the bar, slide around and wear the bar out as fast as the rings. I added the spiral groove to stop the scraping off of the compound and later changed to a much softer steel and put a very rough, but carefully designed, finish to accept the lapping compound, actually allowing the grit to be driven into the surface of the bar. The nasty, scruffy rough finish is full of grooves and valleys of a depth designed to ‘catch’ the very sharp lapping compound, imbedding it into the bar. You then will wear out what you’re trying to lap rather than wear out the bar at the same time. The spiral grooves also cannot catch on the edge of the scope rings as can one which has annular grooves cut perpendicular to the axis of the bar in separate rings. I have very good reasons for every unique feature of my tools. Every aspect has a valid design behind it.”

Kokopelli Scope Alignment Bars
Kokopelli’s patented scope alignment bars have flat ends and work differently than alignment bars which use pointed tips. Kokopelli came up with a flat-ended design because alignment bars with pointed tips can yield a “false positive”, meaning the points can touch when the scope rings are out of alignment. To demonstrate, try this simple experiment. Take two ordinary pencils. With one pencil in each hand, hold them parallel with the pointed (lead) tips touching. Now simply move the outboard end of each pencil, while keeping the tips touching. You can see instantly that the tips can touch even if the pencils are way out of alignment. The same thing can be true of scope alignment bars.

With the Kokopelli scope alignment bars, each bar is an exact cylindrical projection of the interior of each ring. When you bring the bars together, if they don’t mate perfectly, i.e. if there is any gap between the flat ends when the bars are touching, then you know you have an alignment problem. Kokopelli claims that misalignments as small as .002″ can be detected. John Werre explains: “The bars actually are a three-dimensional projection of each ring ‘hole’. You’re looking at a solid representation of the hole through the ring. Put one bar in each ring and you can then compare the axial alignment of the ‘ring holes’ to each other. If the ends match and are flat together you have reconstructed the bars into one [cylinder] and the alignment is PERFECT.” Below, in Figure 1, you can see rings that are out of alignment. In Figure 2 you can see rings that are properly aligned. Interestingly, the misalignment illustrated in Figure 1 did NOT show up with pointed ring alignment bars. This amount of misalignment can create up to 3/16″ of scope tube bending (depending on ring spacing).

Kokopelli Scope Alignment Tool

Kokopelli Scope alignment Tool

The function of the Kokopelli lapping tool and alignment bars are described in greater detail on the Kokopelli website. The lapping tool and alignment bars are sold separately, or as part of Kokopelli’s complete Accurizing Kit shown below. The kit, which combines Scope Alignment Bars, Lapping Bar, pointer rod, and lapping compound in a fitted box, costs $84.50 for 1″ rings, or $91.00 for 30mm rings. For more info, contact John Werre at Kokopelli Products, 3820 Foothill Rd., Kalispell, MT 59901; phone (406) 755-3220. NOTE: Kokopelli has maintained the same prices since 2003. However, due to increased costs of materials, John Werre plans to raise his prices by mid-January, 2010. You can get current pricing by ordering soon.

Kokopelli Accurizing Kit