What year was your browning trombone 22 pump made serial number 144768?
I can say that your rifle was made at the end of production.The
Browning trombone model rifle were only made in the total amount of
150,000 grade 1 rifles.If you contact Browning directly through the
customer service dept,they should be able to date your rifle.I
suspect that it was made sometime in the 1960,s.