Some background towards my statement:
I had purchased some of the original GLOCK G22 mags with the original 10-coil spring, for a G27. When my friend shot these mags, the gun jammed every time. For me, they worked fine for my normal shooting grip, but I could fairly easily make them jam by intentionally limpwristing.
So, doing some research, I found out some relavant info. At one point, G22's were recognized to have issues with jams, particularly when flashlights were attached to the rails. The flashlights prevented frame flex, and caused the guns to cycle a tad faster. Note: this was not a problem with G17's. GLOCK issued an 11 coil mag spring to fix this issue. Evidently, a subcompact G27 cycles fast enough for this to be a pretty major issue, despite having nowhere to hang a flashlight.
Replacing the mag springs made them more reliable for my friend. But I can still limpwrist this gun pretty easy with any mag, even with the stock 9 round mags. I can't limpwrist my G21. I even had a single unintentional jam with the G27 using a stock 9 round mag. And that was a little disappointing. But that's besides the point.
The point is, the slide will cycle faster on the subcompact .40, and the mag springs will be performing that much closer to the edge, as a result.
I seem to recall a thread by another poster, a couple weeks ago, that supported this line of thinking. The guy had some jams using G22/23 mags in his G27. He contacted GLOCK, and he was told that G22/23 mags are not officially guaranteed to feed properly in the subcompacts. IOW, if a G27 is not working 100% with 13/15 round mags, but is working 100% with 9 rounders, then GLOCK considers the gun to be functioning correctly and not in need of warranty repair. Maybe someone here has better search skills than I?
I had purchased some of the original GLOCK G22 mags with the original 10-coil spring, for a G27. When my friend shot these mags, the gun jammed every time. For me, they worked fine for my normal shooting grip, but I could fairly easily make them jam by intentionally limpwristing.
So, doing some research, I found out some relavant info. At one point, G22's were recognized to have issues with jams, particularly when flashlights were attached to the rails. The flashlights prevented frame flex, and caused the guns to cycle a tad faster. Note: this was not a problem with G17's. GLOCK issued an 11 coil mag spring to fix this issue. Evidently, a subcompact G27 cycles fast enough for this to be a pretty major issue, despite having nowhere to hang a flashlight.
Replacing the mag springs made them more reliable for my friend. But I can still limpwrist this gun pretty easy with any mag, even with the stock 9 round mags. I can't limpwrist my G21. I even had a single unintentional jam with the G27 using a stock 9 round mag. And that was a little disappointing. But that's besides the point.
The point is, the slide will cycle faster on the subcompact .40, and the mag springs will be performing that much closer to the edge, as a result.
I seem to recall a thread by another poster, a couple weeks ago, that supported this line of thinking. The guy had some jams using G22/23 mags in his G27. He contacted GLOCK, and he was told that G22/23 mags are not officially guaranteed to feed properly in the subcompacts. IOW, if a G27 is not working 100% with 13/15 round mags, but is working 100% with 9 rounders, then GLOCK considers the gun to be functioning correctly and not in need of warranty repair. Maybe someone here has better search skills than I?
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