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MkV operating instructions

  • Install the jack screw with push pin.

  • Raise the bottom screw with the rotating washer to the correct height to keep the pin on the bottom of the dovetail.

  • Tighten the top set screw and check height. Adjust as necessary.

  • When height is satisfactory, tighten the side screws evenly. Install the counterforce screw opposite the jack screw.

  • When applying force to the jack screw, if the slide tries to move under pressure, tighten the counterforce screw slightly until the slide cannot move.

  • Apply pressure to the sight by turning the Jack screw.

Here's the set up on a 1911 rear sight. Other slides work pretty much the same way.  Photo: Roy Huntington

Accessory Instructions

I recently purchased your sight pusher and it came with accessories that I don't know how to use. Do you have any information besides the one page operating ins

Ed Jennings <>

8:36 AM (32 minutes ago)

to K

Well, let’s see what we can do. The accessories start with the round to square adapter set which consists of two steel blocks with a #12 hole in one side. These fit over the round pins used in the jackscrew. I usually suggest using the shortest pin that will reach. So long as there is a block that will fit the particular dovetail it’s recommend to use one of these. The very small block that has its own jackscrew is for smaller dovetails. Originally designed for S&W front sights. Several other applications exist though. Glock rear comes to mind.

The L shape aluminum block is for 1911 pistols with full length barrels (5”). Remove the rotating flange washer from the bottom bolt, insert the short leg of the adapter into the slide behind the recoil spring housing. The bolt goes into the hole in the adapter. The brass pins can be substituted for the steel pins on any application not requiring maximum strength. They will be kinder to the soft steel sights.

The slide is placed in the frame and elevation determined by the bottom bolt. Then tighten the three swivel set screws by hand. Usually no wrench required. The slide should feel pretty firm in the frame and not move easily at all. The jackscrew will move it, even when you can’t move it by hand. That’s where the counterforce screw (orange plastic cap)comes into play. Installed on the side opposite the jackscrew, in the hole beneath and slightly aft of the jackscrew hole. Tighten a half turn or so at a time until the slide no longer tries to move with the jackscrew.

As to measuring movement, I try to use a flat edge and a caliper on the side opposite the jackscrew. Alternatively, the jackscrew has 16 threads to the inch, or .0625” per full revolution. 

© 2017 Jennings Machine and Tool

Pleasant Grove, AL 35127

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