The gun here has the stylized lion over 'MULLER'
https://www.shotgunworld.com/thread...sxs.591046/?post_id=5344288#post-5344288

I think (but don't know) that the 'M' is more likely Mullerite than French Poudre M.
I have seen a lion over 'S' (not SCH for "Schultze"); possibly Poudre S. I've never seen a lion over 'T'.