Doing a traditional trigger job calls for the sear primary (engagement) face to be cut perpendicular to a line from the center of the sear pin hole as shown here -
https://forums.1911forum.com/showpost.php?p=11355114&postcount=30 . It doesn't matter which sear jig you use for this type trigger job as long as you can orient the sear nose correctly. Sear length is very important. You cannot keep stoning without risking making the sear too short, so careful setup is critical. Some sears are too short right out of the gun or baggy, so check it before wasting time on one that ain't right. If the length fro mthe center of the sear pin hole to the sear nose is less than .4015" get another sear. In fact I wouldn't even use one that short as any stoning would make it shorter.
This drawing is misleading. While it is preferable for the hammer hook to be at 90 degrees to the flat, it is not mandatory as a
correctly mated hammer hook lands tip first on the sear nose. Yes, that is correct and poorly understood, so that "Properly Mated Sear-Hammer" drawing is wrong in the hammer - sear interface. When they are mated as shown in the drawing creep is impossible to eliminate. You will fight it until the cows come home. The tip of the hammer hook should have a .002-.003" radius. The secondary (escape) angle should be cut at a shallow angle to keep the sear from dropping deeper into engagement with the hammer. 45 degrees from the primary face is commonly recommended, but that is too much. It is simply an escape clearance cut. I use about 20 degrees on mine.
I've done hundreds of satisfactory jobs since the late 70s using this method, first with the Tom Wilson sear jig, then with some others less satisfactory, finally settling on the Ron Power Series 1 jig. I now use the Warner True Radius jig as I have found it to be the best of the best. It differs from this traditional method by stoning a radius on the sear nose providing the only truly neutral engagement setup.
