Biltmore Edderd
Actually, I have found, before I became enlightened, that nasty fad heathen smokeless stuff fouls too. And, It's harder to clean than BP or, especially Subs. It doesn't give your position to the enemy, it provides an instant smoke screen to enable one to flank those basty nasterds (Snicker). When them ignorant desperados pop up trying to see thrush smoke, just pick 'em right off (Snicker Snort).
Some Lustrum (several in fact) Us Gov. actually loaded and issued All Brass hulls for the trench guns. Unfortunately, as they weren't intended for reloading, they (the Us Gov.) rolled the case mouth to facilitate function in their (Us Gov's) Trombone guns. They fed slicker'n'snot too. Just a shame they rolled the case mouth. Makes em a real PITA to reload.
I understand there are those (not me) who have in fact worked up acceptable smokeless loads for the All Brass hulls. Magtech says not recommended for smokeless. I think that is because the current MagTech hulls are quite similar in construction to the old "Balloon Head" pistol cartridges and the pressure spikes are quite different. Couple of guys who contribute here have indicated they load smokeless in their MagTech hulls. Dunno
Play Safe Out There
PS: A long time ago . . . In a Galaxy far far away . . . I was known to tote a Trench Gun into the bushes. I was actually issued All Brass Buckshot ammunition from Dubbia Dubbia and Two. Kinda went with the Korean Conflict "C" rats we were issued too.
PSS: I really really like your Trench Guns two (also) (Snicker Snicker giggle)