There has been much speculation as to whether the "top-end" of a GSG 1911 can be used with a standard 1911A1 [.45ACP] "lower" to, in effect, make the GSG "top end" a .22lr "conversion unit".
First, I would like to preface my remarks by saying the foregoing contained in my post is my opinion only. I do however, invite discussion as to my conclusions.
So, this morning my curiousity got the better of me, so I disassembled my GSG 1911 .22lr to see if the "top end" would "go" on a standard 1911A1 frame and theoretically "work" as a .22lr "conversion unit".
To start lets discuss the function of the GSG 1911 .22lr as issued. Unlike the standard 1911A1, when "assembled" the GSG barrel is "fixed" to the frame with a cross pin, the slide stop, and a hex head screw, all at the breech end. The bottom of the GSG barrel has a single lug attached to the bottom of the barrel. The cross pin, slide stop, and screw all fit into this lug to secure the barrel to the frame. The barrel bushing in the GSG is not "fit" to the barrel, as in a standard 1911A1. As the GSG barrel is "fixed" [ie. non moving] at the breech end, the barrel bushing serves more just to keep the recoil spring plug in the slide and serves cosmetically to resemble the standard 1911A1. Also, for note, the GSG 1911 slide employs a firing pin block safety.
In a standard 1911A1 the barrel is not "fixed". It employs a "link & pin" setup that allows the barrel to move up and lock into the slide as it moves in operation. In assembly, the barrel, while contained in the slide, is attached to the frame with the slide stop. The "link & pin" setup is contained between a set of lugs on the bottom of the barrel that when assembled sit in a slot milled into the top of the mid point of the frame. The barrel bushing has somewhat of a "fit" to the barrel, on the muzzle end, of a standard 1911A1. The kind of fit the barrel bushing has to the barrel usually functions to assist accuracy, given that the barrel "moves" at the breech end during operation. In theory, a fitted barrel bushing in a standard 1911A1 will produce better accuracy than a "generic" barrel bushing.
So, I tried to "fit" the GSG 1911 topend on the following 1911A1 frames:
Colt Government 1911A1 .45ACP [Series 70]:
The GSG bare slide would fit on the frame. However, when the GSG barrel was assembled in the GSG slide, the GSG slide would not go on the Colt frame. The issue being that the single fixed lug on the base of the GSG barrel will not fit the cutout in the Colt frame that the standard 1911A1 barrel lugs with link & pin setup would fit into. The GSG barrel lug is larger than the cutout in the Colt frame. To make the GSG barrel fit would require aleration to the Colt frame. As well, the GSG 1911 magazine fit into the Colt magwell but was very loose. I did not go farther here.
Norinco 1911A1 .45ACP:
Same results as above.
Colt Delta Elite 10mm [Series 80]:
The bare GSG slide would not go on the Colt Delta frame as the ejector on the Colt frame did not allow clearance for the slide to go on. One solution would be to change the larger ejector to a standard .45ACP ejector, then likely the slide would fit on the frame. It was noted that the GSG fixed barrel lug would fit the slot milled in the Colt frame, likely as the barrel lugs on the 10mm barrel are "beefier" than those of a standard .45ACP barrel. So, with a change of "ejector" it may be possible to actually get the GSG topend on the Colt Delta Elite frame. The GSG magazine fit the Delta's mag well but was very loose as in the above tests, however. It should be noted that, even if the GSG topend could work with the Delta lower, would the firing pin safety on the GSG slide be compatible with the Series 80 firing pin safety "stuff" in the Delta's frame?
Anyway, after the above, my conclusion is "you can't get there from here". Well, not easily, anyway.....
I would say that, "as issued" you can't get a stock GSG 1911 .22lr "top end" to readily function as a ".22lr conversion unit" with a standard 1911A1 .45ACP lower.
I am not really alll that disappointed though, my GSG 1911 .22lr works fine, just as is.
NAA.
First, I would like to preface my remarks by saying the foregoing contained in my post is my opinion only. I do however, invite discussion as to my conclusions.
So, this morning my curiousity got the better of me, so I disassembled my GSG 1911 .22lr to see if the "top end" would "go" on a standard 1911A1 frame and theoretically "work" as a .22lr "conversion unit".
To start lets discuss the function of the GSG 1911 .22lr as issued. Unlike the standard 1911A1, when "assembled" the GSG barrel is "fixed" to the frame with a cross pin, the slide stop, and a hex head screw, all at the breech end. The bottom of the GSG barrel has a single lug attached to the bottom of the barrel. The cross pin, slide stop, and screw all fit into this lug to secure the barrel to the frame. The barrel bushing in the GSG is not "fit" to the barrel, as in a standard 1911A1. As the GSG barrel is "fixed" [ie. non moving] at the breech end, the barrel bushing serves more just to keep the recoil spring plug in the slide and serves cosmetically to resemble the standard 1911A1. Also, for note, the GSG 1911 slide employs a firing pin block safety.
In a standard 1911A1 the barrel is not "fixed". It employs a "link & pin" setup that allows the barrel to move up and lock into the slide as it moves in operation. In assembly, the barrel, while contained in the slide, is attached to the frame with the slide stop. The "link & pin" setup is contained between a set of lugs on the bottom of the barrel that when assembled sit in a slot milled into the top of the mid point of the frame. The barrel bushing has somewhat of a "fit" to the barrel, on the muzzle end, of a standard 1911A1. The kind of fit the barrel bushing has to the barrel usually functions to assist accuracy, given that the barrel "moves" at the breech end during operation. In theory, a fitted barrel bushing in a standard 1911A1 will produce better accuracy than a "generic" barrel bushing.
So, I tried to "fit" the GSG 1911 topend on the following 1911A1 frames:
Colt Government 1911A1 .45ACP [Series 70]:
The GSG bare slide would fit on the frame. However, when the GSG barrel was assembled in the GSG slide, the GSG slide would not go on the Colt frame. The issue being that the single fixed lug on the base of the GSG barrel will not fit the cutout in the Colt frame that the standard 1911A1 barrel lugs with link & pin setup would fit into. The GSG barrel lug is larger than the cutout in the Colt frame. To make the GSG barrel fit would require aleration to the Colt frame. As well, the GSG 1911 magazine fit into the Colt magwell but was very loose. I did not go farther here.
Norinco 1911A1 .45ACP:
Same results as above.
Colt Delta Elite 10mm [Series 80]:
The bare GSG slide would not go on the Colt Delta frame as the ejector on the Colt frame did not allow clearance for the slide to go on. One solution would be to change the larger ejector to a standard .45ACP ejector, then likely the slide would fit on the frame. It was noted that the GSG fixed barrel lug would fit the slot milled in the Colt frame, likely as the barrel lugs on the 10mm barrel are "beefier" than those of a standard .45ACP barrel. So, with a change of "ejector" it may be possible to actually get the GSG topend on the Colt Delta Elite frame. The GSG magazine fit the Delta's mag well but was very loose as in the above tests, however. It should be noted that, even if the GSG topend could work with the Delta lower, would the firing pin safety on the GSG slide be compatible with the Series 80 firing pin safety "stuff" in the Delta's frame?
Anyway, after the above, my conclusion is "you can't get there from here". Well, not easily, anyway.....
I would say that, "as issued" you can't get a stock GSG 1911 .22lr "top end" to readily function as a ".22lr conversion unit" with a standard 1911A1 .45ACP lower.
I am not really alll that disappointed though, my GSG 1911 .22lr works fine, just as is.
NAA.
