The Cosmi is a very high-end boutique Italian sporting shotgun. It has all the looks and lines of a single shot break-action gun, but hiding inside is a long recoil self-loading action and 8-round magazine tube.
The video I have today is really only half a video – I filmed this footage back in the summer of 2015, anticipating that we would pair it with some footage at the range using the gun. However, when we got out there, we realized that we had the wrong recoil spring for the ammunition on hand, and the gun wouldn’t cycle reliably. I have not had another opportunity to film a Cosmi since, so I figured I might as well post this much to give at least some information on the mechanism. I do plan to film a complete (including much better disassembly and explanation of the mechanism) video on the Cosmi, but I don’t know when that will be feasible.
Long recoil? Just onespring ?
The spring shown is almost certainly for the barrel.
There’s a tab in the middle of the lower receiver that looks like it interfaces with the recess on the bottom of the bolt (and probably cams the locking lever into battery). I’d guess that it’s a carrier that compresses a bolt recoil spring in the stock.
I think it’s just the one spring.
That’s a video from the factory, in Italian, with English subtitles. It isn’t clearly shown, but I am pretty sure that there’s no second spring for the bolt. What I think is going on is that the bolt hooks into that piece there on the right side of the magazine tube, and that’s what pulls it forward using the action spring underneath the barrel. I’d love to see the loading sequence in one of Othais’s animations, but I doubt anyone will ever do the work on this thing.
This is an amazing piece of work, and if you watch that factory video, stand in awe at the seemingly austere and primitive workshop it comes out of. I’m starting to see why Italian aviation before and during WWII had such tiny numbers of extraordinary aircraft–If they were doing it all by hand-crafting, like these shotguns? No wonder they never got anything significant into mass production…
Actually, disregard that idea about the hook on the right doing what I was thinking it did… That’s the part that actuates the loading lifter.
There’s got to be a link in the upper that pulls the bolt forward, because I don’t see anything in the stock, nor do I see a tail on the bolt or a hole for it to go through.
I wish Ian had showed more of that upper than he does…
Separate motions of bolt and barrel are needed, and I can’t see how they’d be possible without a second spring somewhere.
The first (workshop) video you posted shows a track on top of the mag and a slot above the round mag hole in the back of the lower, appearing to reinforce my first impression. The guy in the first Russian video pulls out what looks like a spring, though it isn’t clear whether it’s for the bolt carrier or mag. 8:10 of the second appears to show a guide track on top of the stock part of the mag tube too. The other possibility I’d considered was a concentric spring under the first one, but the Russian video appears to show that there is only one under the barrel.
One more link, which has two videos in Russian in it:
Still really unclear how that bolt works…
There’s a wedge above the mouth of the magazine, just right of the hammer, in central position, that almost surely pushes the bolt forward.
It seems to be spring-loaded, with the spring into the butt of the rifle.
Strongarm found the patent, and linked to it in his post down below this one.
You are indeed right–There’s a bolt recoil spring above the magazine.
Thanks, Kirk, and thanks to Strongarm for the research.
Happy New Year!
This video answers a “range mystery” that’s been troubling me for years. I was on a skeet range back in the 1990s, and the guy shooting a couple of bays over was shooting something that I wasn’t paying attention to at first, but struck me as being incredibly “off”. It looked like a standard break-action shotgun some of the time, but the damn thing was shooting strings of shots like a semi-auto. It took me awhile to figure out what the hell was weird about it all, and I never got a chance to ask what he was shooting, but it must have been one of these.
This is an amazing action, and to know it was designed back before WWII is really incredible. That thing is a piece of mechanical art, and even though I’m not a shotgun sort of person, I’m shocked I’ve never heard of it.
its obvious the intended use, illegally hunting with extra rounds. and for the rich only.
It’s only b/c of the Democrats we have a 3 shell limit on ducks. You can hunt upland game w/ any # of rounds, and burglars w/ a full-auto belt-fed shotgun (Grand Juries frown on leaving out the same big screen tv box night after night w/ the trash.)
US patent. 1802198
Recoil spring over the magazine tube, inside the stock…
You got it… I couldn’t find the patent, earlier. Fascinating design.
That is a beautiful shotgun,and very Italian.
Elegant and superbly crafted.
I had the opportunity to put a few rounds through one of these some year back I believe at one of the NSCA nationals. A beautiful shotgun without a doubt but I wouldn’t want to have to clean it all the time though. I remember the checkering was unbelievable.
I worked in the Cosmi factory in 1986 for a few weeks as I was gunsmiths for the Australian agents. They are nothing short of gun art. things that Ian din’t shoe are the 2 round cut-off on the left side of the magazine housing, the ease with which the hole magazine feed system and firing group can be remove for cleaning. The magazine tube takes about 7 deg downward turn in the pistol grip as dose the bolt spring tube that is fasten to the top of it.If you get the chance Ian the stock comes off very easily if you close the top lever by depressing the lever hold open found in the cutout for the action extension then undoing the screw in the back of the stock (most of these are made with a wooden but plate) the screw has a spring loaded D-dent to stop it coming loose and screws into the back of the magazine tube.They are beautiful. Ian dint say it but they are long recoil.
Same sort of old world craftmanship that produced that WW2 german bullpup silenced rifle. All that metal hidden in a wooden stock with nary a crack
That bullpup silenced rifle was a hoax, as far as I’m aware.
Fascinating gun. I was trying to figure out why it was made then remembered that in France at least, shotguns carried during field hunts were carried broken open so that it was obvious they were safe – when I went on pheasant hunts with my dad back in the late 60s no one used a pump or auto shotgun – all were break open side by side or over under, which of course are pretty much limited to 2 shots. This Cosmi system allows the best both worlds: large capacity, while still allowing a visually safe carry at a hunt that didn’t allow pump or autos.
Hi Kirk when I was at the factory in 86 I was told that that is exactly why Mr Cosmi destined it that way so that he and the people he was hunting with could see that it was safe at a distance. It could then be closed and ready to fire instantly if the chamber was loaded and the hammer cocked.