I used 748 years ago for all my NRA match rounds with a Colt HBAR. Not any dirtier than other powders, and would often go 350-400 rounds w/o cleaning. As stated above, 748 is temp sensitive. Many of us would go to the firing line with ammo in a soft-sided cooler, and take care to keep rounds out of the sun.
There are better choices available now such as CFE and TAC.
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