Shotgun inserts can be very effective. The Germans have made all sorts of technical marvels in insert barrels, but they tend to overdo it. Not much point in having a .22 Hornet insert which cost more than a rifle in the same caliber.
I used to make shotgun inserts in .22 Long Rifle caliber by offsetting the liner to compensate for the rim diameter. The inserts were surprisingly accurate.
The pictures are from an experiment to shoot .22 LR in a 577/450 Martin Henry. In theory, the bullet should just stay clear of the .45 caliber barrel, but unfortunately it didn't, and while the bullet didn't actually tumble, it was all over the target. I should probably have angled the bore line of the insert slightly towards the center of the rifle barrel. The extractor was spring loaded and the "bobbed ears" would allow the rifle extractor to pass the insert rim. When turned 90 degrees, the inset would pop out when working the lever.
The most silly insert I made was a "sleeve" for shooting 16 gauge shells in a twelve gauge gun, but as an excuse I was young, poor and someone had given me several boxes of 16 gauge for free.
Cap'n Morgan
I have 3 of his long adapters. Mostly I have not played with them much. I consider it an investment in case of SHTF and ammo becoming harder to find.
Take something like a Handi Rifle .30-30 20 ga combo. Add a 16" rifled adapter for .45acp. Well it may not have the accuracy of the dirty thirty. But it is quieter, and would work perfectly well for popping a rabbit/coon at closer ranges. It would do so with less noise. For the cost, seems like a pretty cheap insurance policy.
Less weight to carry than a full barrel. Adds flexibility and options. I'm still learning how to get the most accuracy from these inserts. But they show potential IMO.
I put myself on the waiting list for a bunch of the long inserts a while back. Just got an email that the the 18" 12 Gauge to .45-70 are in stock so I ordered one. Going to use it in a Baikal TOZ-66 20" SXS, it'll be a fun experiment. Been looking for a NEF/H&R Handi, Buffalo Classic, or Shikari but if this works out maybe not.
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 |