Transitioning from Gen 3 Glock to Gen 4 (Light Fit)

[ZGXtreme]

Did Glock alter the cut in the frame between generations? On my Gen 3 21C my X300 fit snuggly and there was no play. On the Gen 4, it wobbles fore and aft and slightly rocks side to side. Would the larger plate remedy the issue or is the "U" plate still appropriate and I need to utilize a different option to tighten it up?

[kevN]

No difference in fit on my Gen3 vs Gen4 G17 with U plate. Not sure if it might be more specific to the G21.

[ggammell]

I've seen DeFoor out some aluminum foil on rails to tighten the fit. Might be worth a shot.

http://www.kyledefoor.com/2009/12/mounting-tips-and-eotech-secret.html

[ZGXtreme]

I've seen DeFoor out some aluminum foil on rails to tighten the fit. Might be worth a shot.

http://www.kyledefoor.com/2009/12/mounting-tips-and-eotech-secret.html

That ended up the fix, ended up about postage stamp sized and 8 layers thick.