help

Question
i have a 22 pump short barrel 22 that belonged to my grandfather  model 62  5a  ser 6    488758 inter arms  trying to find out how old it is my dad would be 85  mint cond

Answer
Interarms was importer only.
Its now out of business. Your Rifle is  Rossi 62.
It should say made in Brazil on it.  These were introduced in 1978 and imported with the Interarms
name till they were forced out of business by BATF in the 1990s. Rossi was imported again by Brazil Tech in 1997.  I would Email Rossi in Brazil to assess its date of manufacture.
[email protected]

This rifle is a copy of the Winchester model 1890.
Rossi stopped making repeating long arms  a few years ago.
Taurus another Brazilian arms company now produces this rifle.
http://www.taurususa.com/products/gunselector-results.cfm?series=22L

Your rifle worth $175
There no collectors interest.
Have fun shooting it!
Rossi makes sold guns.