Wednesday, May 11, 2016

Trigger Warning

So yesterday morning I dropped the ZEV Fulcrum Ultimate kit in the Robar Glock 17. This replaced the  ZEV connector/NY1 spring combination, dropping the trigger pull from a nominal seven pounds to four and a half.

Gone was most of the weight on the takeup. Gone, also, was the abrupt "wall" in the trigger pull before the break.

Given that I have largely shed myself of the bad habit of "riding the reset" and instead let the trigger reset and prep it again during recoil so that I'm ready to break my next shot as the sights settle, the lack of the vigorous reset shouldn't be a handicap.

The problem is that this particular trigger setup makes very little tactile distinction between "prep" and "bang", as evinced by the shot that grazed the target's shoulder, caused by the shot breaking before the sights had dropped back to the center of the target.

While I'll put more time in with this trigger in the 17 before moving it to a purely fun gun like my Glock 20, I'll likely be going back to the light connector/NY1 spring combination, and for reasons other than just trigger pull characteristics.

A gunsmith I know, Bob Howard back in Knoxville, once commented while looking into a Glock's guts "I can't get over the fact that these things are filled with toaster parts." And they are. Little coil springs and sheet metal stampings comprise the working bits of a Glock. The basic trigger return spring is a coil spring with a hook on each end that operates in tension: You pull the trigger, the spring stretches, the gun fires, and the spring contracts, resetting the trigger.

As anyone who has maintained a fleet of Glocks, whether for a police department or rental counter, can tell you, the trigger return spring is probably the most frequently broken part on a Glock. When it fails, you can keep firing the gun, but you have to push the trigger forward after each shot. The NY1 trigger spring, on the other hand, is a V-shaped piece of olive green plastic with a coil spring nestled between the two arms of the V. It works in compression and, while I'm sure that they can break, I've never seen a broken one with my own two eyes.

The problem is that with the standard connector, the NY1 spring gives a trigger pull in the neighborhood of nine or ten pounds. When used with a factory Glock competition connector (or an aftermarket equivalent) you get a seven-ish pound pull with an even takeup that leads to a rolling break. Imagine a DA revolver trigger with only half an inch of travel.

That's the setup I've been using on my guns (except my carry gun, which is stock at the moment, mostly because I haven't gotten around to changing it. It shoots fine, though, so I'm in no hurry.)