Howdy Castboolits!
It’s been awhile since I posted anything here, but now I find myself doing something stupid again and want to share. Extensive web searches tell me that I am not exactly alone in my dumb project but I might have stumbled on a new exciting permutation that hasn’t been done- who knows?
I watched the 12g from hell boys with great interest but never wanted to test the velocity limits of my shoulder that way. I am fairly recoil insensitive- I will shoot 45-70 all day, even a good amount of marlin only data stuff, but full power or magnum 1oz slugs are just not so fun. I cast a ton of Lee 7/8 and 1oz slugs and tried many different loads through a mossburg 500 rifled scoped pump 12g. They were super fun at trap shooting velocity- soft shooting and nice big holes in paper- but the accuracy just wasn’t there.
I’m finally getting around to a project I’ve wanted to do for a long time but never got around to doing because it’s stupid and pointless and even a little bit of theater or dress-up or whatever.
The idea is, like 12gFH, to exploit the shotgun bore “loophole” and have what would otherwise be a destructive device. I want decent but not necessarily amazing rifle accuracy and a bolt action rifle look and feel to the shooting experience. The end goal is a reasonably soft shooting .730 caliber bolt action rifle, hopefully launching a full bore 12g round ball at slightly supersonic speed. I’d like to hit a pie plate at 100 and ring steel often if not always at 200 with some hold over.
So far I have a bolt action marlin 512 with a 2-7x scope. This is not an especially beefy action with a single rear locking lug that is part of the bolt handle, but it has a thick barrel with crisp rifling. 1 in 27” iirc.
I have magtech brass, LP and magnum LP primers, longshot, and just got some blue dot. I have 11g over powder, cushion, and lubed fiber wads from dixie. I also got some .730 balls from Dixie- I haven’t decided if I want to invest in the full bore spitzer slug of my dreams with driving bands, grease groove, and even maybe a crimp groove, so these will do nicely for now. They’re pure lead I think meant for brown bess shooting? They stuff through the marlin bore with a good equator of engraving that gives me confidence they will both swage down without excess pressure, and hopefully not blow through and smear into the rifling at the moderate speeds I plan.
So that’s what I have! My first nervous range trip was a great success. Safety, accuracy, and a very soft shooting load:
CCI Magnum LP
26 grains Longshot
1 thick overpowder card, seated firmly by hand
3 thick greased fiber cushion wads, ending 3/16-1/4”ish from top of brass
.730 PB roundball
The load was compressed and crimped over the equator of the ball using a brass plumbing fitting- 5/8” FLR cap, which simultaneously pushes the ball down and crimps the brass over.
I did buy the RCBS cowboy tool which is useless- just get their shell holder to make priming easy. Decapping is peg & hammer and crimp removal requires annealing and a tool steel mandril off my lathe.
So that’s my adventure so far. The 26gn load was very accurate at 25 yards but shot soo soft like 38 special in a levergun. Tomorrow is my 2nd trip and I’m turning up the heat very slowly with a handful of 26, 27, 28, and 29 grain Longshot loads to try.
Longshot book loads go into the low mid 30s in smaller plastic hulls with more efficient plastic wads, so I know I’m way safe, but I think if 29-30 grains doesn’t get me to 100 yards without measuring drop in feet compared to 50 yards I will switch to the blue dot and work up slowly again.
Any suggestions or comments are very welcome but please be aware that I am chasing fun, safety, and some modest accuracy. Top loads and scary pressures are not on the menu and warnings against wildcatting are not helpful.
Thanks!
Radar