I bought a Paramount .45 back in November of 2020, non-threaded barrel. I shoot 100 grains of Blackhorn (by weight) and the Powerbelt ELR 280 gr bullet. I foul the barrel with a charge of 25 or 30 grains of Blackhorn and a sabot and one of many .40 cal pistol bullets I have laying around. I run a single dry patch down the barrel after fouling and then between shots, just for consistency.
It will shoot a 5 shot group of less than 2" at 200yds and will shoot an 8" group at 400yds, off a bench.
I went to Nebraska back in mid December for a deer hunt and the Saturday afternoon before I left Arkansas I shot a fouling shot through it and then ran a single dry patch down the barrel. I loaded it the following Monday morning in Nebraska before going hunting. I killed a deer that Friday with that load. Cleaned it when I got home and will foul the barrel again before shooting it again.
I've shot this rifle about 50 times since I got it and have tried shooting with a clean barrel. It shoots about a 4+ inch group at 100yds when cleaning the barrel between shots, with usually one flyer out of 5 shots that's 6" or more off.
I consider it's accuracy to be extremely good, with a fouled barrel.