Aftermarket Vent Rib?

[Dean Romig]

Most often it is the last three digits of the gun's serial number stamped on the bottom of the rib.





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[Randy Roberts]

The last 3 digits under the rib can be tricky to spot for my eyes however outdoors they tend to jump out at me. The lack of the numbers does not mean the rib is not correct, I have seen guns that letter that lack the numbers under the rib. I have a BHE that letters as a VR gun and it has one digit or letter only under the rib. I have tried to convince myself if is a 5 for the grade but honestly I cannot tell if it is a 5 or an S or possibly neither and I have stared at it a bunch.