If it has a rifled barrel, don't waste your time. T/C made a screw-on choke for their .45 Colt / .410 pistols. It helped, but still not good patterns. I think the shot column gets to spinning with the rifling and gets slung all over the place. I experienced better patterns from .22 revolvers with snake shot / rat shot than from rifles. I have an American Arms derringer in .45 Colt / 2.5" .410. You need to get so close it gives the rattler an even chance. See if you can find a true .410 barrel to fit.
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |