i recently purchased a Glock beavertail backstrap for my wife's G-19, Gen 4 from Glock. I have a slightly newer G4 G-19 that included the beavertail backstrap as part of the original purchase and it fit like a glove and feels quite tight and secure. I installed the recently purchased one on my wife's G-19 last night. I installed it and find that the beavertail on her G-19 flexes at the top instead of being tight (more description below), like on mine.
The part looks right but the actual tail can be pulled back and down at least a 1/4" off the top of the back of the pistol. When released it will spring forward and look normal. This flexibility should not affect operation of the pistol (I will check it out at range of course), but it seems wrong.
The recently purchased beavertail looks identical to the one on my newer G-19. I wonder if my G19 has the "nose" which holds the beaver tail more securely (from the installation guide, step 5, "Note: The beavertail backstrap fits older Gen4 pistols without the small nose") OR whether there is a product problem. I could take apart my beaver tail backstrap to see if there is a "nose" on it, but it took me awhile to get the pin to line up right and don't want to mess with what is working right. This "nose" business may explain why some folks have significant problems installing the beaver tail
WHEREAS others have said it is simple (see comments).
I have a note to Glock Customer Service, but would appreciate any input on this. Thank You, MCJ