Large bore that can accept normal pistol bullets and shoot all copper

I have been looking at airguns for... A long time. Well, I have an older single pump pneumatic target rifle in .177, but this would be a more general use PCP rifle.

I think I might finally jump in. One issue is I am interested in shooting lead free. Actually, specifically copper slugs. The reason for this is I shoot indoors. My plan is to swage them. Probably using a Corbin press. The setup is fairly insane in cost, so I have been avoiding it. I may offer the slugs for sale around cost, including machine cost, to help transfer the investment and allow purchase of copper at higher volumes. It seems like a Corbin press is very low maintenance. As much as I frown on anyone reloading while watching TV, it seems entirely reasonable to swage while doing so, so my labor cost would be minimal.

Anyways, I would also like the option of being able to shoot lead bullwts. I have cast lead bullets before, part of why I want to stay away from it now, but it may come back up. I also know I can buy an absolute ton of lead bullets for next to nothing from people I know who cast as a hobby. I will just have to shoot outside and go through a very very detailed cleaning before shooting indoors again if I switch to lead.

So, this leads me to: are there any airguns that can handle a common firearm bullet? Firearm bullets of the same diameter seem to run a higher volume(longer with no cavity), but pure copper v. Lead should eliminate most of the weight difference.

I know one can shoot 357/9mm soft lead out of some and it will more or less swage to correct size in the barrel since it is so soft. It seems that is less likely to work with a pure copper slug.

I am not terribly worried about barrel wear. I shoot enough volume barrel changes are part of the deal. Despite what I saw posted here in a tangent thread, copper is definitely going to wear a barrel more than lead even if it is substantially softer than steel. An hardened steel ax still dulls when cutting a tree. I am just concerned about squibs and other safety concerns or damage to the airgun.
 
I believe most of the extreme big bore rifles are sized for either pistol or muzzle loader common bullets. I would call them before trying copper tho. Copper bullets use high pressure to open up slightly and make a seal. I don’t know if any air gun make’s enough pressure for that. Bismuth or zinc may be a better option but bismuth but bismuth is more expensive than lead and zinc. It could end up cheaper to build a vent filtration hood in your indoor range. I don’t know how much lead goes in the air with an Airgun but it’s probably much less than a powder burner. I’d just get a blood test once every 6 months and do something about it if the lead levels get too high. Whatever you feel is best tho. Hope this helped
 
I believe most of the extreme big bore rifles are sized for either pistol or muzzle loader common bullets. I would call them before trying copper tho. Copper bullets use high pressure to open up slightly and make a seal. I don’t know if any air gun make’s enough pressure for that. Bismuth or zinc may be a better option but bismuth but bismuth is more expensive than lead and zinc. It could end up cheaper to build a vent filtration hood in your indoor range. I don’t know how much lead goes in the air with an Airgun but it’s probably much less than a powder burner. I’d just get a blood test once every 6 months and do something about it if the lead levels get too high. Whatever you feel is best tho. Hope this helped
I would be swaging copper pellets/slugs myself. There is a cavity in the base to assist with expansion.

I don't think firearm bullets rely on expansion anyways. The rifling lands are smaller diameter than the rifle bullet. If you were to attempt to load a bullet from the muzzle, it would not drop through. I guess when it hits the rifling there would be some smooshing around.
 
I would be swaging copper pellets/slugs myself. There is a cavity in the base to assist with expansion.

I don't think firearm bullets rely on expansion anyways. The rifling lands are smaller diameter than the rifle bullet. If you were to attempt to load a bullet from the muzzle, it would not drop through. I guess when it hits the rifling there would be some smooshing around.
Even though the bullet would not fall down the barrel it’s still not a perfect seal. Early cartridges suffered from this because they had less velocity than muzzle loaders and that’s why I wonder if it would be a problem with Airgun’s. The name of the action a bullet takes when expanding under pressure to make a good seal is called obturation. It might be worthwhile for you to Google it or use it as a keyword when you’re searching if it’s a problem with solid copper bullets at low velocity. Just an idea. At the end of the day you might need to just experiment with it. I’d buy some bullets and try them before spending all that money on a sewage machine.
 
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There is a lot of talk about obturation, but it really isn't happening, at least not in pistols and quite a few rifles. There simply isn't close to enough pressure, especially in factory loads bought off the shelf at Walmart. The people talking about it are just repeating what they have said on the internet. Pull a bullet and mic it. Shoot a round into a bucket of water and mic it. Base and along the bullet. It is just like the cylinder gap on a revolver. That gap on a well tuned revolver is .005. a lot of production revolvers are double that and I have seen functioning guns that have huge gaps. It doesn't need to be perfectly fit to the barrel. .001 gaps aren't having much effect.

There aren't a whole lot of solid copper slugs around and they are quite expensive.

Maybe I just grease them... I am really worried about the oversize though. I probably just need to speak with Corbin. I spoke to the owner there years ago and he was helpful, but he knew a lot more about firearm bullets than airgun slugs.
 
MY question is how many years to recoup your investment in equipment , supplies , and your time ($26.00 an hour

?)https://www.americanrifleman.org/content/tested-the-polycase-arx-bullet/
maybe this might be a safer route
Setting up a injection molding operation is definitely considerably more expensive and complicated than swaging. The ARX bullets themselves are not available for sale as a component yet as far as I can tell.

And, although I do value my time, $26 an hour probably isn't what I would use in this calculation.
 
I cannot find a single instance of swaged copper ammo. I see all sorts of machined brass and copper but even Barns solids aren't swaged.
The space, cost, and necessity of providing 3-phase power preclude me using a lathe and a bar feeder in my garage. If I owned a shop it would be a quick bit of code and easy setup.

Corbin is using atomized copper powder to do it. At the small volume he sells it I have worked it out to $.30 a projectile. Considerably less than I can find solid copper projectiles.
 
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I've been wondering about this myself, my worry would be that if there's enough power to push a pure copper bullet out the barrel?
When a pellet/slug is pushed trough the barrel it get's crimped by the rifling. Lead is soft, so easier to push into the shape of the barrel.
Copper is harder so would require more power to push trough, so you might need to use higher pressures or the bullet might get stuck in the barrel?
Would a tapered barrel cause a clog or is there enough power in an airgun to squeeze out a pure copper bullet?
 
You can cast with zinc...instead of lead...all new wheel weights s are zinc...They are also free.. Elvis ammo on YouTube and others have made slugs out of zinc wheel weights... I'd go zinc if lead not a option.. Free is a good price.. For me I love my soft cast lead and powder coat....But I don't have any range restrictions..