Mike, you get an A+ on my report card...
You may want to explain to them how NOT blocking-supporting parts (large open areas, which heat and cool at different speeds and temps) will cause them to warp as well....i.e., the rifle receiver you mentioned was probably cased without the bolt or a dummy bolt in place.......and possibly without the trigger block in place ?
The warping is minute, but nonetheless it must be fixed....this CAN ALL BE AVOIDED IF DONE PROPERLY...AS MENTIONED ABOVE....
Most gun metals and tool steels case to a depth of about .005..not much more.....
The greatest harm to any case color is U.V. light...leave your gun in the sun for long periods, or in a glass doored gun cabinet, exposed to sunlight and the case colors will rapidly go bye-bye.......that's why the old guns just have the "mottled" look, still very hard...but the colors are gone.....and there are some you will see at the shows 100+ years old that look like new...they have been "kept in the dark"..!!!!
I use dummy screws etc. to secure actions etc., in the crucible...as I am sure you do as well.....
Best Regards,
