Thanks, have a local guy here that I have had do some work in his back yard shop, re profiled my acr barrel, cut my racker Dove tail, and now this. We did not flat top the slide clamped it in the jig/vice and went to cutting. Then installed barrel marking where I wanted the holes and drilled those. Deburred, reblued the cut then I went and shot 30 rounds to clean the barrel up and sight in. If all goes well should shoot in a match this sat. Will have a buddies stock trubor to compare the two, although mine had popples and a recently added pt evo grip so not really apples to apples, but it will give both of us a idea, then he will decide if he wants some holes added. As far as chronograph goes I have some loads that were loaded pure popples, that I need to use up, then I will chronograph and know what and how much was lost, I anticipate 20 to 40 fps