That's exactly what I did and it works fine with all my other magazines. Problem was it's a new gun with a floor plate different than them, and it came off earlier than I expected.Just put your other thumb over the spring/subplate as the floor plate slides off.
There is no reason for that to ever happen if today's 1911 manufactures would simply make spring plugs to mill spec.I shot myself in the forehead with the recoil spring bushing from my 1911 .45 Auto.
I never did find the plunger that shot out of the tube on my first 1911.
owner claimed to have the world record for putting the front end cap from the recoil spring in the Government Model pistol into the florescent light fixture.
Guy I worked with was using a power wire wheel brush on an engine block and one of the bristles shot off and pierced his eye. It almost entered his brain. Worn an eye patch from then on.It always amazes me how many guys do stuff, even live fire, without eye protecting.
Discharging firearms, anything that's under spring tension, most power tools, working with pimers, protect those eyes