Has anyone ever experienced a barrel that falls off the frame when the mainspring lock is removed? Usually I need a mallet to unseat the barrel. How is it tightened? The barrel is so loose even when assembled there is play.
i had one like that years ago , don't know if what i did was right or not but it did work , IF you do try this you have to be very carefull but what i did was take the Grip frame and put it in a vise with padded jaws ,
pretty much what you are doing is bending the lips of the frame up so they make more contact with the bottom of the barrel
i put only the very edge of the frame in and then very very slowly put a little presure on the frame , i would take the frame out and try the barrel on it, if it was still loose i would put it back in and tighten it down a little more , i kept doing this until i had a nice tight fit between the frame and barrel
maybe some one else will have a better way
if you do to much you could ruin the frame so again if you try this be very careful
what Hank says is correct and one must be very careful,NOT to "crush" or mark the top edges on BOTH sides, as well as keeping it "uniform", you can deform it or make it out of square, quite easily....'if you do NOT want to attempt to "adjust( refit) the grip frame, you can put a piece of electricians tape or a match book cover or some such, thin piece of cardboard, and place it in the notch ,up front that hooks into the under side of the receiver,,, then tap the upper assembly in place,,,this works and will keep it tight until the next time you remove the upper receiver,then do it again......it works.
Gentlemen, I closed leather lined vise .005" on the frame and the bbl fits mallet tight. Perfect.
For years I'd been fighting the re-assembly process with this pistol. I discovered that it wasn't only the bbl falling off it, the sear would rub on the front nose of the hammer so the hammer would not flop properly when re-assembling. After some light stoning (in a non critical area of the hammer) the Mk II is running like it always should have!