I'm also experimenting with modifying some M&P mags and CZ mags to use from the carbine. You have to Slash the notch in the entrance in the mag so it will lock in. I don't own any Glocks. oil on everyhting else. When I shipped mine to Ruger for mend https://watermelon-lemon-lost-mar14589.blogminds.com/what-does-ruger-p89-for-sale-mean-29563095