Well, the striker is not "always down" once the slide is racked. The striker is not fully cocked, but it is more like two thirds cocked rather than "always down".
Based on measurements with a cutaway and standard pistols, the striker spring compression, by length, with a round chambered is about half of what it is at the point of firing. Total compression is about 11mm in a standard-sized Glock and the preload is 5 or 6mm, can't remember off the top of my head.
That works out to roughly 25% of the striker spring energy stored by the preload compared to what is stored in the spring immediately at the point that the striker is dropped to fire the gun.
Yup, you take down the gun, take the RSA out, slip a round into the chamber, just leave enough out that you can slip the rim under the extractor, and let the barrel slip into place. Replace the RSA, and slip the slide back on, just till it "clicks" locked.
The gun is now loaded, with the trigger unset. All you have to do to make the gun ready, is move the slide back enough to load the striker and youre all set. You can actually draw the gun and "cock" it one-handed, with a little practice.
I had a Glock armorer tell me the only thing he could see wrong with it, was the firing pin block is not engaged, and that it "might" fire, if dropped just right. Other than that, and maybe "why", he didnt see anything wrong with doing it.
With the trigger to the rear (in the "fired") position, all of the passive safeties on the gun are inoperative.
- The firing pin safety is held in the upward ("Fire") position by the trigger since the trigger is to the rear.
- The trigger safety is moot since the trigger is already rearward.
- The cruciform portion of the trigger bar is behind the safety ramp which means that the safety ramp is not restraining the trigger.
Basically the striker can move freely in the channel--a condition that should never occur in a Glock with a chambered round.
On the other hand the firing pin spring is under no tension at all, which is sort of a plus except when you consider that in order for that to happen the firing pin must be unrestrained which means that since the firing pin safety is in the "fire" position
the gun is not drop safe.
The above is consistent with my understanding of the operation of the Glock firing mechanism per my own study and per the instruction provided in the Glock armorer's and advanced armorer's courses. It was further verified by observing the condition/position of the various internal passive safeties on a cutaway Glock pistol.
Besides the safety problem, here are a few other disadvantages to this approach.
- You have to rack the slide (at least a small amount) to reset the trigger so the gun can be fired. Your handgun is now a "handSgun".
- If you don't pull the slide back far enough you won't reset the trigger and the gun won't fire.
- If you pull the slide back a little too far you'll eject the chambered round which means in this situation, at best, if the next round chambers, you could have achieved the same effect by carrying the chamber empty. At worst you may cause a misfeed by partially operating the slide.
- If you accidentally eject the chambered round by pulling the slide back a little too far you may not have pulled it back far enough to chamber a new round especially since you were trying NOT to pull the slide fully to the rear. The gun won't fire in that condition and may misfeed.
- Pulling the slide back only partially to reset the trigger doesn't let the slide go into battery with any force or velocity which can result in the gun not achieving full battery. That can result in a failure to fire or, if the gun is badly worn, it may fire slightly out of battery which could be dangerous.
In summary: Carrying a Glock set up this way is unsafe and offers several ways for a user operating under stress to put the gun into a condition where it will not fire, will jam or perhaps could fire out of battery. It is an interesting way to make an otherwise fully functional Glock non-dropsafe and to carry a chambered round without the pistol actually being ready to fire.
There is another issue as well. The gun appears to be chamber empty to anyone with a basic knowledge of Glock operation. Anyone who rigorously follows the gun safety rules should check properly to insure that is really the case. That aside, it's highly unlikely that most folks would consider the possibility that someone actually took a gun apart, loaded the barrel while it was apart, and then carefully put it back together while loaded to achieve a condition which is not otherwise possible. It creates a situation that makes the gun appear to be in a condition different than reality.
It should go without saying, that when you have to disassemble a firearm, load it while disassembled and then reassemble it loaded to achieve a particular condition, you've put the gun into a condition that the manufacturer never envisioned. That means you may uncover idiosyncrasies of the design that no one else has been "ingenious" enough to find before you--and that's generally not a good thing.
For those who wish to carry a Glock chamber loaded without a holster, or in a soft holster, or in one that doesn't protect the trigger, there are ways to accomplish that safely that have none of the drawbacks of the above method. Probably the simplest and cheapest is to use a Saf-T-Blok.
