doublegunshop.com - home Forums General Discussion Double Rifles, Paradox Guns & Gauge Rifles @ doublegunshop.com 2.75" slug in 2.5" chambered Cape Gun

I wonder if there is a significant pressure problem with shooting a 2.75" 1oz. rifled slug (non-sabot) in my circa 1914 Sauer 12ga X.43 Mauser Cape Gun. The shotgun barrel has a 2.5" chamber and is marked 'nitro proof' and the Federal slug I have been wanting to try is marked 'max load' (don't think I've seen a slug shell that wasn't). The choke measures IM with a drop-in choke device. Barrels are steel. Greener crossbolt.

The gun probably was not meant for modern slug loads, but is in pretty good condition and is built to withstand the rifle cartridge. Am I gonna blow something up if I try this out? The rifle barrell shoots the old CIL 385gr factory loads pretty well to point of aim with the 100yd leaf site, and I'd like to see how the slug matches up.

Thought I would seek advice here before I did something unusually stupid...Geo

I know folks hate to answer a question like this one; too many variables and not much literature. Don't even try to get an answer out of a gunmaker or ammo mfgr.

I think the gun is stout enough since it was built to handle the rifle pressure and recoil, so the question is the shotgun barrell. Based on information to the effect that the longer shell in the 2.5" chamber does not in itself cause an appreciable pressure rise I don't see how the chamber length is an issue. The payload of the slug is 1oz which shouldn't be a problem. The only problem I see is the higher pressure of the Saami spec modern slug shell.

I'm not going to hold anyone responsible for what I may decide to do, but I'd like to know if everyone thinks I'm making a big mistake.

I would not do it. For one thing the recoil will be severe. A saboted slug would be better for the choke restriction.

Thanks Mike, I wondered if the saboted slug might not be a better choice. I have some on hand, but they're 1 and 1/8oz (OUCH!). I'm not particularly recoil sensitive, but a 12ga slug out of this gun might change my outlook on that. I'm deer hunting with the cape gun this year and would like to have a back-up for the rifle shot. I guess I could use buckshot (I can't find any of those in 2.5" either), but if the slug happens to shoot to point of aim I'd rather use that...Geo

http://www.chuckhawks.com/shotgun_slugs.htm

When in doubt, look it up. The above article answers a lot of what I was wondering about. Think I'll stick with the 1oz foster type slug. I posted the link in case anyone else might be interested...Geo

Yes, there is big problem. Slug will cut a piece of plastic case, when you fire 2.75" slug ammo in 2.5" chamber.
Can't say about pressure, but nothing good to shoot factory loaded slug ammo in 1914 old gun. One way to load ammo yourself.