The 12 gauge 1 1/4 oz. loads generate 9,900 psi chamber pressure and well within the norm for when those guns were being built.

The only concern of mine is the old wood. But next step is something like this,


http://www.highplainsgunstocks.com/winchester-model-12-premade-stocks-for-sale.html

Eat your heart out, doublegunners!!!!