Gentlemen,
Please know that the SAAMI specification for 10 gauge 2 7/8" and 3 1/2" loads pressure is 11,000 psi.
The SAAMI 12 gauge 2 3/4" and 3" pressure is 11,500 psi.
The SAAMI 12 gauge 3 1/2" pressure is 14,000 psi.
That extra 3000 psi is 36.6% over 11,000. The surface area of a 10 gauge compared to a 12 gauge is 9% larger so potentially there may be a 9% pressure drop but I have no data to prove this. Even if it would only be a 27% gain in pressure that doesn't seem to be safe.
I believe that one can do as they chose so long as it does't hurt others but...
Charlie if you blow off a finger or two you'll type worse than you do now! It is hard enough to read your posts now since punctuation escapes them! I do however try to read them because they are full of good wisdom.

Please do not endanger any of your typing fingers...
Let's be careful out there!
Mark