I'm also experimenting with modifying some M&P mags and CZ mags to implement in the carbine. You need to Slice the notch from the entrance with the mag so it can lock in. I do not possess any Glocks. I just paid out $three hundred for the blue P85 in https://stephenhcnxb.ziblogs.com/32251797/5-essential-elements-for-ruger-shotguns