Will this work on a gsg 1911 80 series?

If the GSG is a government style, then you need the government drop in. The rear of the frame is different between it and the commander. Be aware that even though they call it drop in, that isn't always the case. There may be minor fitting required, which will depend on your GSG. I have never installed one without having to file and fit, I've done over 30 of them. I would personally reach out to Wilson and/or look on 1911 forums about your model to see what others have had success with. If you've never installed one, I'd also look up videos and see what tools you may need and such, just to get an idea. Hope that helps and best of luck.

Will this work on a browning 1911 380?

Based on my limited experience with the Browning I would say no. The Browning frame is much thinner than the 45acp variants and this would not fit in that slot.

Will this work with ria 1911a1 fs model?

This is for the commander version, you may need the government version if your frame has the longer tangs at the rear. If it's the rounded (like the tactical) models this one should work. Notice either way and any brand, drop in is not drop in, in the normal sense. There may be minor fitting required or you may get lucky and it does drop right in.

Will this fit a Springfield Mil-Spec better than the government model drop in, which leaves a 3/16” gap?

There's no good answer here. No 1911 part is actually "DROP IN" . If they do in fact drop in its just good luck on your part. As a TRUE GUN SMITH for 30+ years I can say that I have NEVER dropped in a grip safety or a thumb safety without having to tweak it a bit. I wish I could be more specific but drop in and go shootin is rare.

Manufacturer	Wilson Combat
Color	Dark Blue
Weight	57 g
Material type	Plastic
Batteries included?	No
Item model number	WC429BC
Package Dimensions	10.16 x 7.11 x 2.54 cm; 0.28 g
ASIN	B000EQ05L4

Beavertail Grip Safety, Drop-In, Commander

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