S&W 638

[HDH]

I think I have a S&W 638 airweight but there is no model # on the gun. The frame is stamped 2104 the cylinder and butt are stamped 75299 and airweight is stamped on the barrel. is this a 638 it has a shrouded hammer. also can I use +P ammo. All help is appreciated.

[normanvin]

This clip shows a 638. There should be a model number somewhere on the gun.

[Philbert]

I think I have a S&W 638 airweight but there is no model # on the gun. The frame is stamped 2104 the cylinder and butt are stamped 75299 and airweight is stamped on the barrel. is this a 638 it has a shrouded hammer. also can I use +P ammo. All help is appreciated.

Try opening the cylinder and looking under the crane, just in front of the trigger guard.

[brian]

I think I have a S&W 638 airweight but there is no model # on the gun. The frame is stamped 2104 the cylinder and butt are stamped 75299 and airweight is stamped on the barrel. is this a 638 it has a shrouded hammer. also can I use +P ammo. All help is appreciated.

sooo, there is not a s&w logo or name on the pistol?

[normanvin]

Try opening the cylinder and looking under the hinge, just in front of the trigger guard.

I believe Philbert is correct. It may also be under the grip.

[brian]

Try opening the cylinder and looking under the crane, just in front of the trigger guard.

now he might find it...

[Philbert]

now he might find it...

Yeah that. According to the S&W manual:

“Plus-P” (+P) ammunition generates pressures in excess of the pressures associated with standard ammunition. Such pressures may affect the wear characteristics or exceed the margin of safe- ty built into some revolvers and could therefore be DANGER- OUS. This ammunition should not be used in Smith & Wesson medium (K frame) revolvers manufactured prior to 1958. Such pre-1958 medium (K-frame) revolvers can be identified by the absence of a model number stamped inside the yoke cut of the frame (i.e., the area of the frame exposed when the cylinder is in the open position).

Doesn't say about how to tell if a j-frame is +P safe.

[HDH]

Thanks everyone. with the cylinder open the yoke is stamped 2104. I will take off the grips and check there. I think i will not use +P

[HDH]

The gun has the S&W logo and has airweight on the barrel. It has wood round butt grips

[Noah_Zark]

Thanks everyone. with the cylinder open the yoke is stamped 2104. I will take off the grips and check there. I think i will not use +P

The number on the crane is an assembly number. Ignore it ("Crane" is the S&W term, "yoke" is the Colt term for the arm upon which the cylinder swings out. Sort of a "Concealed Carry Permit vs LCTF" thing as applied to revolver parts, but I digress).

With the cylinder rotated out of the frame, look at the thin portion of the frame directly under the barrel where the crane mates into the contour of the frame, specifically under where the ejector rod would be if the cylinder was closed up into the frame.

There will likely be dot-engraved numbers or letters there. The word "model" will likely not appear. The model number itself will likely be three digits, a dash, and either one or two digits. Something like "638-6" as an example.

Below the model number may appear the serial number, this time three letters followed by four digits -- "BHN 4423" for example. The serial number is not always present on the frame under the crane on newer S&Ws, but if it is present on your revolver, it will match the number on the bottom of the butt.

HTH,

Noah