RE: Black Diamond XR today
I believe T7 is a lot more worrysome as its a sugar based powder and sucks up moisture. APP/ BM3 are also sugar based.
I remember someone here posting a picture of a loaded sabot/bullet and the sabot did not fill in the rifling and left gaps where, obviously, any moisture/ water will easily get to the powder and ruin the charge. Just another thing to think about.
Never noticed any stains in my bores but its something to look our for in the future.
Edit: conicals
Thats why i stick with Pyrodex with the powerbelts. Triple 7 shot dead on on a clean bore and 3" higher on a fouled bore. I hate that so i decided to just stick with pyrodex.