Hi Paranator,
Maybe I can clarify things for you, glass is made of sand, it is hard and snow white, it don't realy peen the steel like sand or aluinum oxide, it hits and breaks and leaves a brighter whiter stain finish with out leaving pits in the steel, it will show any imperfections in the steel if it isn't polished out first.
the glass will realy bounce of a hardened slides. Aluminum oxide and sand will cut the steel.
I think these bead blasters have gotten to be the lazy mans way of polishing something, it looks like Kimber uses play ground sand at 400 psi to cover there tracts, all the corners are rounded from rock tumbling, this just opens up the steel, makes it more prone to corrosion and the blueing don't stick worth a hoot.
If your going to use glass polish out the gun first then glass blast and your have a nice uniformed white satin finish.
If you want a nice matte deep gray finish I use aluminum oxide, this is the next thing hardest to diamonds, it will cut the steel and leave a dull grey finish, first I polish the machine marks out and dust it in 220 grit, it is about fine as baby powder, this will not leave deep pits and trap dirt, easier to clean. It will also cover more imperfections in the steel. Blueing does seem to penatrate deep using this method.
I don't have much use for sand, it will cut and pit the steel and leave a matte dirty white finsh but, if you like that type finish go for it. Blueing don't stick well.
Colt uses 100 grit, half glass, half aluminum oxide on there stainless pistols. It is a little to coarse for my liking, I polish out the pits and dust off in my 220 a/o. It does give the steel a classey iniformed look. Hope this helps you out.
