The serial number.
The serial number for an RG Industries Model RG 31 revolver is located on the frame at the bottom of the grip. To find it, remove the grip and look at the bottom of the exposed frame.
Look on the grip frame under the grip panes and on the bottom of the frame under the barrel.
It all depends on what pistol you are talking about for example on the Revolver it is a grip panel where you hold the revolver, if you are talking about a Semi-Automatic Pistol, there are two things, the grip panel, and the ammo magizine.
under the grip plate
This question can be answered if more information is provided. Describe where marking are found on barrel or top strap, serial number on bottom of grip frame and under left grip, condition of the firearm, what type of finish?
On the frame and the grip frame.
What is the grip made of?
For identification purposes.
It left H&R with one. Anything is possible. In this case, it's a felony waiting to happen to you. That's silly...I'm sure someone's corrected this by now...For an old H & R revolver, remove the grips (one screw) and you will find the serial number stamped into the frame...usually at the bottom edge! The H&R Model 922 revolver was made in several model series and a bunch of variations from circa 1925 up to 1986. Every example that I have owned/own or have seen has had a serial number stamped either on the front strap of the grip frame, if equipped with one piece grip (Rice frame) or on the bottom of the butt strap, if equipped with two piece grip panels (square butt frame) - many times it was also stamped into the left side of the bottom strut of the grip frame - can be seen only by removing the left grip panel. If no serial present - it has probably been removed - see above.
First of all describe the gun. Is it a revolver, or a shotgun? A revolver has a grip but so does a shotgun (actually a for end).
Frame and bottom of grip