Aftermarket Glock™ Frames, what is Sear engagement, and how OP Trigger Bars can fix problems 

In an engineering office, far, far, away, lies a coveted data set otherwise known as the Technical Data Package for all of Gaston Glock’s ever-reliable creations. Included in this data are production tolerances for the 34 individual parts that make up America’s favorite 9mm pistol, the Glock 19. None of us will ever see that data so we are limited to $25,000 disco lasers, micrometers, and good ol’ American reverse engineering.

Many companies (this one included) have spawned out of necessity, daring to improve upon the admired Austrian’s labor of love. There are aftermarket components for every piece of a Glock™. Some are lackluster, some are dangerous, some add a safety element and others aim to increase accuracy, decrease split and reload times all through thoughtful design, processes, and coatings. Enter Overwatch Precision.

Many years ago, companies like Polymer80 and most recently SCT Manufacturing, Shadow Systems and Palmetto State Armory have released their take on a few of Glock’s favored platforms: The Glock 17 and 19.

Add slide manufactures like Zaffari Precision, Brownells, Grey Ghost, Zev Industries, DV8 and others and you have a potential recipe for difficulties in compatibility due to a what is known as tolerance stacking.

One important detail that many gun owners overlook when building their carry pistol is the importance of the relationship between the frame, slide, and trigger for proper cruciform engagement. This is the percentage of the cruciform on the trigger bar (the cross shaped feature at the rear of the bar) that is contacted by the striker lobe when the slide moves forward back into battery after ejecting a spent casing. It is this process that partially cocks the striker as the slide moves into battery. Glock™ requires AT LEAST TWO-THIRDS engagement when the trigger is at rest in its forward position. Sounds easy, but any less than 2/3’s and the potential for a binary trigger exists.

Trigger reset, binary triggers, as well as other normal cycle of operation issues all typically have one thing in common: somewhere in the mix of OEM and aftermarket parts, tolerance stacking has exceeded the limits for that particular striker due to a combination of component interactions somewhere in the frame, slide, connector, or striker.

Some manufacturing processes help minimize or eliminate these potential problems. At Overwatch Precision we utilize Progressive Die manufacturing coupled with an intense post production and pre-assembly QC, but at a cost. Dies are incredibly consistent and equally expensive but can produce 25,000 identical parts per rum. Add in the cost to have a very talented individual hand deburr and then place each and every OP bar in a custom jig to check cruciform height and we have rapidly rising production and quality control costs. In the end, this allows us to guarantee a great and safe product to you, our valued customers.

Short story is Overwatch Precision trigger bars for Glock™ Gen 1-4, Gen5, and Slimline 43/43X/48 are consistently .008-.010 higher at the cruciform than OEM Glock™ trigger bars and are manually deburred prior to their NP3 or electroless nickel coating. This intensive treatment and attention to detail ensures that the end user gets the best possible trigger bar for their OEM Glock™or Glock™ clone build.