Will the Umarex XP-40 fit in this?
Checking the list of compatible guns, I do not see the XP-40 listed, so no
Is this metal or plastic?
It's made of plastic.
is this airsoft or a BB gun?
It's a BB gun, NOT airsoft
Semi auto BB gun
Could I fit an S&W M&P in this?
will this come assembled or unassembled?
What clips fit this?
Enter this in our search bar: Beretta 19-Shot Stick Magazine, Fits...
is this a one shot rifle or can you switch from one shot to auto
It is semi automatic only
How do you obtain the fittings for other model pistols? All mine had in it was the one for the XBG ...
Contact Umarex USA. They will be able to tell you what pistols will fit.