SIGforum
P320 back plate catching on FCU

This topic can be found at:
https://sigforum.com/eve/forums/a/tpc/f/150601935/m/5990040874

December 27, 2020, 04:35 PM
W_kemp
P320 back plate catching on FCU
Hello! Really looking for some help here.. I just finished my build off of the P320 custom works FCU and am having an issue. I have a grey ghost precision slide and I have tried both the back plate they provided as well as an NDZ back plate I bought for it (pictured) and both back plates are catching on the FCU when removing and putting the slide on. This does not seem right to me and cannot figure out what the issue is. Any help is VERY appreciated! Trying to figure out how to input images will post them below

https://imgur.com/gallery/NHE4hoV
December 27, 2020, 05:12 PM
sigfreund
The rectangular tab that extends down from the aftermarket back plate in your pictures appears to be wider than the corresponding part of a standard factory back plate. It seems that that part may be contacting the safety lever and causing the problem. It even looks like there may be a bit of a ding in the finish of that part that could have been caused by rubbing on the safety lever.

Have you compared the factory and aftermarket parts by measurement? (If you don’t have a factory back plate, I could measure the width of one for you to compare with the ones you have.)

Is it possible the aftermarket back plates were designed for the pre-“upgrade” guns? (I don’t know if that was something that was changed and whether it could have been the source of the problem, but ….)




6.4/93.6

“Wise men talk because they have something to say; fools, because they have to say something.”
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December 27, 2020, 05:25 PM
W_kemp
I do not have a factory back plate being that I have the custom works FCU, I never thought that the dimensions may be slightly different for the custom works FCU over the original p320.. Is there a difference? if so that may explain things and i will have to order a factory back plate asap.
December 27, 2020, 05:38 PM
W_kemp
so I ordered a factory backplate to check. I also took the back plate provided by GGP that came with the slide and filed it down slightly and it goes on and off smoothly with that. will check the factory plate when it arrives and see if the sizes are different
December 27, 2020, 05:56 PM
sigfreund
Good that you got it fixed.

For information, the width of the part we’re discussing of a factory plate measured 0.191 inch. I have a “custom works” FCU as well, and the space between its ejector and safety lever is the same as another standard P320’s.

Welcome to the forum, BTW.