Part A:
I have a Holosun 407K mounted on my CZ 75BD and wanted to mount a Holosun 507C on my Kadet 2. My old eyes demand a dot these days. After searching the internet and not finding much, I decided to craft my own mount. I wanted it to be as minimally invasive as possible while still keeping the excellent iron sights.
(Note: Pics are posted on RimfireCentral - I don't have an image host).
The top slide on the Kadet is too thin to mill so I decided to drill and tap for two screws (enough for a .22). I started with a Weaver 62 base shortened to 2.1 in. I then milled a shallow 3/8 in. groove in the bottom to tightly and squarely fit the Kadet’s sight rail. This ensures good alignment. With the base properly positioned, I marked, drilled and tapped for two 6-48 screws. Depth control on the drill is critically important to avoid going too deep. I used both a regular and plug tap for the threading. An extra cross channel was cut in the Weaver base for best positioning of the sight. The Holosun was then mounted with its picatinny adapter. (I used a small lathe and drill press for this work but I’m sure it could be accomplished with hand tools as well).
The resulting setup was very stable and accurate and I’m sure would work well for many people.
However, I disliked how high the sight was above the slide, especially compared to the 9mm slide. I like my dots and scopes as low as possible and thought I could do better.
Part B:
I figured that if I attached a mount plate directly to the slide it would reduce the height considerably.
For $10 I purchased a Glock universal mount plate that comes with adapter pins and screws for many optics including the Holosun 507C. I filed and milled the hump off the bottom until it was flat (should’ve got the aluminum plate instead of steel – easier to work!). Again, I milled a 3/8 in groove to fit the sight rail. I used the original weaver mount as a template to mark and drill the mounting holes in the new plate. These holes were countersunk and the screw heads filed until they were flush across the top so that the optic would sit flat. The two front positioning pins also had to be shortened.
The optic now sits much lower on the slide. I am satisfied with the result although I will probably go back and clean things up a bit. Maybe blue it properly, too.
Hopefully, this post will help others accomplish the same.
