The gun dates to the period when Parker Bros. was fabricating Twist and Laminated Steel tubes in house.
A Lifter with Twist barrels; ‘PB’ in a shield, ‘T’ for Twist, J.L. and an unknown mark

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Drew, that unknown mark I believe is a 4 that has been broken. Likely the prestruck weight?
We’ve seen that broken 4 before.
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