Originally Posted by
BillSWPA
I prefer shoulder holsters with a figure 8 harness because it keeps the pressure off the back of my neck.
The harness should be adjusted so that the gun and magazine pouch come as high up under your arms as possible, but not so high that the grip of the gun is being pulled outward away from your body. With the straps so adjusted, the gun will stay in place even when you bend forward, eliminating the need for tie-down straps. I discourage tie-down straps, because as you move, they will pull the gun in ways that will not help concealment.
Horizontal shoulder holsters are one of the few holster types for which I prefer a thumb break. Gravity works against keeping the gun in the holster. A combination of a thumb break and tension screw is helpful, but the tension screw cannot be too tight. In the case of a 1911, the retention strap should pass between the hammer and firing pin. Some holsters are designed to pass the strap around the spur of the lowered hammer, and are to be avoided. For a Glock, I do not find a significant advantage or disadvantage to the strap passing over the back of the slide or the backstrap of the grip. Either way, I find that I have to release the thumb break with less than a perfect grip.
The attachment of the harness to the holster should cause the holster to cant slightly grip down, and should also cause the gun to cant with the grip angled towards your body. The Miami Classic revolver holsters do this better than the semiauto holsters, although their semiauto holsters have proved acceptable to me, and the Kramer holster is particularly good for this.
Although the vast majority of shoulder holsters with figure 8 harnesses are horizontal or diagonal, Galco and FIST both make vertical holsters with such a harness.
Before I knew better, I tried some cheap nylon shoulder holsters. Concealment was generally not as good as better quality leather holsters, and access speed was often compromised by poor thumb break design and/or the potential for snagging. A thin nylon strap can easily get caught between the hammer body and hammer spur of a revolver.
Ken Null makes a few very interesting upside down holsters, my favorite of which is the SKR. This holster is extremely fast when drawing with either the strong hand or weak hand, although a weak hand draw will cover your own torso. A discreet draw is not possible, since the pull-through snap will be loud. I did not find the harness to be comfortable.
When drawing from a shoulder holster, be aware of the potential for covering your own arm as well as everyone within a 180 degree arc. This is the least of your concerns if you need your gun to stop something really bad from happening, and certainly would not concern anyone who carries AIWB, but ti does create a risk. You will not be able to practice drawing with live ammo on any public range, even those that permit drawing from strong side hip holsters.