410 Case Forming from 303 Brit for round ball or slug use

So I finally picked up this little 410 break action that I bought about 18 months ago.

Now to make cases.

Well, the first thing I found is that 303 Brit cases are too small and way too short - this is a 3" chambered gun. Even so, I can still open the case body enough to fit better and cutting an angle on the forward side of the rim to fit the chamber. But will this produce satisfactory result? It's a long jump from case mouth to the lead. I'm hoping the right cup or wadding will hold the ball or slug central.

I should add that making cases from brass stock is do-able for me if I need to. So is field loading of cases (I'm not going to make

Any thoughts and ideas would be most welcome. Or safety warnings!

What about 405 Win brass??

303's work fine in my H&R break barrel.

Thanks both.

Are 405 cases available to us then? Well of course I could check for myself. Thanks for that tip.

Taylor, are you shooting slug or ball from your 303 cases? How are you loading them? Even using this thing for shot should be a lot of fun.

Try 444 Marlin cases if you can get them. They seem to work better than the 303's. They too will be a bit short but just adjust your wad column accordingly.

Thanks, Reg.

I'm using shot(7.5). I've been researching slug loads.But it'll be after Christmas before I can get serious.

My plan is to get some 9.3x74r so I'll have a longer shell and play with that too.

Give me a little time and I'll look/dig up my load data and share that with you.Tomorrow most likely.

303 works great in my H/R you can fire form those cases with about 5 grs of Herco and a paper wad I just used CCI primers some times it took two shots to straighten out the shoulder, 444 marlin base works as well.

Any ideas on the round ball, wad or wadding, wadded slug and so on?

I have thought of a shuttle cock style slug (or 410 'pellet'). That would a little tricky but I do have an idea.

http://www.endtimesreport.com/survival_reloading.html

Try this sight, some good info.
CD

That is a good site,there is another...Ed Harris..I think.

My thoughts on a slug was to use a .40 cal lead(of course) bullet.

There was a member from Murray,Ky. who did some .410 loading,but I don't remember who it was.

If you can get 9.3x74R cases, these will fire-form to 3" .410s.

Attachment 182994

I made a set of tapered mandrals on my Poor Man's Lathe and drilled a hole in a piece of 1" steel for a Wack a Mole kind of sizing die.
I pull apart surplus .303 then Size the cases and use the Berdan cases in my 410.
I have loaded them with everything from Shot to round balls , and even 9mm cases filled with lead.
I shoot the salvaged bullets in Boxer primed cases or in my 7.62x54s

+1 for 444 Marlin

Just so you dont think I am FOS and Yanking your chain

I never doubted you for a moment. :drinks:

I have made my prototype case but I need to make a larger expander - I also have a cheapo benchtop lathe. It can do quite well but is slow so cannot do shiny smooth mild steel machining but it turns grade 8.8 bolts just fine, which is what I use for mold die and expander making.

Anyway, I'm going to look for 405 Winchester brass, failing which, 444 Marlin. I wouldn't mind getting 9.3x74R cases. Those would be perfect. The chamber length is 76mm to take the crimp so that would be the ideal case length.

40cal round balls should work with the right cup or wadding, I should think.

OK--- this is what I do...

black powder:
30 grains pyrodex--volume
over powder card--cut from card board
1/8 lubed felt - cut from cowboy hat from yard sale--TC bore butter
1/2 oz shot
overshot card..same a above...seal w/elmers glue

cards and wads are 7/16

Alliant 410;
12 grains
over powder card
1/2" of cork filler - cut from cork board-walmart
1/2 oz shot
overshot card--seal w/elmers glue

I will ad pics later on of the kit I made

For cheap Slugs, the empty 9mm cases filled about halfway with lead worked great.
Plus being metal Jacketed, it would be good for your "Dangerous Game Rabbits" that you have in N Z
I hear they run in Gangs and raise havoc for the farmers.

Quote:

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Originally Posted by 303Guy

Thanks both.

Are 405 cases available to us then? Well of course I could check for myself. Thanks for that tip.

Taylor, are you shooting slug or ball from your 303 cases? How are you loading them? Even using this thing for shot should be a lot of fun.

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They may well be available to get them into New Zealand, which I have always considered one of the most sensible countries in Australasia. But I don't think you can get them out of the US through regular channels. Not long ago I got 24ga Magtech cases from Buffalo Arms, but even now their website says "Due to federal regulations we cannot ship rifle and pistol brass outside of the U.S. Unless we ship them through an exporter. Shotgun brass is excluded from these regulations. If your order has rifle or pistol brass on it we will automatically remove these from the order and ship the balance with out contacting you."

As it happens I wanted it for a 24ga shotgun, but I could have had it to load for a .577 Snider. Imagine the hammering armed crime is taking from this! They do list "low stock" of .410 cases, though only 2½in., at $25.98 for ten.

Could I tentatively suggest, without giving offence, plastic cases? If it is a black powder gun, you have a splendid excuse for buying a cheap single .410 to fire smokeless cartridges in. Turned brass cases may not last well enough to justify the cost and trouble, even if you have the facilities. But it wouldn't take too much in the way of equipment to extend a .303 case, trimmed to an inch or so, with 15/32 K&S tubing, which is common (and unbanned) on eBay. For a shotgun used at shotgun pressures, I think you would be all right with the big rifle no-no of cautious soft-soldering at the rear of the case.

BPI has some neato "125 gr Thug Slugs" for the .410 and they have the wad attached. I'd use .444 marlin cases, but that's because I already have some.

Federal makes some 2 1/2" .410 slug ammo that has 125 gr slugs running at 1775 fps!, and they are pretty cheap. This ammo is way above a .357 magnum pistol and would turn your little shotgun into a reasonable deer gun for smaller deer. 50 yards is about it for this round.

To keep it simple I'd just buy a box or so of Winchester 3" shot shells with #6 shot in them and reload those with the little Thug Slugs.

Then you'd get your complete chamber fill out and be able to reload them easier. You should be able to get 5+ loads out of those hulls as they are pretty well made. I have shot these in my M6 Scout and they are pretty vicious little poppers. It also makes that gun quite a bit more useful.

Randy