Ain’t it a pain?
Designs like this gets me wondering what the blank were they thinking. Unlike most mags on the market the Glock uses double retention, a button and tab on each side of the mag at the floor plate.
Here I will try to explain how I got the floor plate off and my modification that keeps the double retention feature while keeping the force needed for disassembly within reason. It’s been years since I made this mod to all of my Glock mags so I might be a bit rusty.
Yes the 10 rounders are more difficult to flex because of the thicker plastic. The tool needed to squeeze the sides of the mag is similar to a slip joint wrench but bigger than the usual tool found around the home or shop. This tool will have deeper jaws and longer handles. If the jaws are not rubber coated/padded then some form of protection like tape may work. Place the front part (the side that faces toward the front of the gun when mounted) of the mag on a table with the floor plate off the edge of the table. Insert a steel screwdriver like a Phillips into the buttonhole of the floor plate and angle the driver toward the front of the mag pushing the inside retention plate away as much as possible without breakage. Squeeze the mag body sides near the tabs with the pliers and push the floor plate using the driver down which is applying force to the floor plate in the direction of removal.
Prior to initial disassembly you may have noticed the tabs at the floor plate are shaped only to aid assembly not disassembly. Use an X-Acto knife or box opener on the tabs on each side of the mag body to angle the tabs. In other words make it look symmetrical. This is enough to reduce the force needed for disassembly within reason IMO. The floor plate is not modified at all and the pliers are no longer needed once the mag is modified.
I find many folks either never disassemble their Glock mags or they break the tabs off completely. Me thinks my method is a good compromise.
