Tim,

It is his gun, his money and in a way his Gunsmith. As a friend tell him what you truly feel about the situation. And as a very good friend if it all ends up in a disaster commiserate with him and under no circumstances say I told you so. You will stay friends and in the end a true friendship is worth far more than just money and a not well repaired gun.

The only lessons in my life I truly did learn from where the ones I paid for!