I"m busy building a mouse-gun, I had a friend draw it in CAD and we then send it for laser-cutting. We had 4 sets cut, he kept one set for his build.
The pistol will be really small, 7" long and about 3/4"thick and will be a .22 caliber. The handles will be Wild Olive but its going slow. I don't get time in the workshop every day but hopefully be able to finish it soon.

a mouse gun? That sounds pretty good. I could have used one of them the other night when I had a weasel in the living room. Instead I got my pellet rifle. But hr refused to come back and show his face.

The small pistols are called mouseguns on the internet, over here we call them Derringers or miniatures. I'm building the little one as a novelty, the barrel is a off-cut from fitting a "sound modulator" to a friends .22-250. The thing was a fishing pole with the silinder attached.
I have a Airforce .22cal airrifle for pest control, packs a nasty punch.

I use a 5mm Sheridan Silver Streak pellet rifle and that thing is very powerful. I have owned for over 40 years I believe, and it still works great. When I was a kid I used to squirrel and rabbit hunt with it all the time. Shot a lot of bunnies with that thing.

I never heard of derringers called mouse guns. Pocket pistols, belly guns, a adies friend.. but I like that mouse gun description.

I had a sheridan blue streak in 5mm. It was the greatest squirrel killing gun around. I wish I had that gun today.

! have one that's almost 40 years old. The seals are bad and it leaks air when you pump it up now.