This one had me really scratching my head since I have had very few problems with mine.
I have been guilty of 'upgrading' some with newer parts though.
Got an old M1-carbine that was former military...
Surplus parts for newer models were everywhere and dirt cheap.
The front band had been greatly improved with thicker metal, a good grip on the barrel, and a bayonet mount that you can mount lasers and lights on.
They were only $16.
Original:
Newer:
Also changed out the useless rear flip-sight, for the very adjustable, more rugged, newer one.
Original: