Barrel walls on Brit 12s often have barrels below 24 thou. and are in proof. I have a nice London SLE made in the 1930 - in proof and with barrels of about the same thickness as the ones you posted about.

I think I would worry if the barrel were much under 20 thou. and some lightweight 2" 12s came from the factory with barrels below 20 thou.

If you like the guns, buy them.

C Man
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