.....interesting question, and a new one for these boards - or at least I've never seen it mentioned here. As I understand, India, or rather the British in India, made the smoothbore SMLE's to fire a round lead ball out of an unnecked .303. That just happens to be about the same size as the .410, only a little shorter I think.
It would seem to me that it would be easier to neck down a cartridge that to neck up one. In this case, I'd worry about splitting the neck. If I were going to try this, I'd probably load a little Bullseye in the cartridge and then fill it up with Creme of Wheat, and then pack the neck real tight with paper or such. Then fire it and see what happens. My guess? The neck will split. If not, you're good to go. Annealing the neck might also be desirable. Mind you, this is just my idea, I've never tried it. YMMV.
You got it! 5gr bullseye and cream of wheat on top. Just a bit of TP on top of that, (only to keep the contents from falling out, NOT as a plug!) You want to use NEW unprimed brass. DO NOT expect previously fired cases to give a good result.
Hold rifle vertical, pull trigger. Caution, this will be just as loud as a noise blank, so don't upset your neighbors. A garage or a basement would be a good idea rather than your back yard if you do it at home:eek:
Oh by the way, you do want to keep the blanks vertical to make sure that the bullseye stays in the BOTTOM of the case.
First acquire the following Hornady Egg-shaped Expander Buttons and stems , .338, .358/.375 and .40 cal, and some die bodies to suit. ( .45/70 die bodies work best)
Lube the inside of the neck of the case and pass through all three buttons, in sequence.
I do this on a Dillon 1050-Super, so the finished, expanded case (Just like a "unfilled" .303 Cordite case) comes ready for fitting my "Inner tube" for Long Blank production (but that is another matter.)
The expanded case will not be split ( very rarely) if the step by step expansion is carried out... I also do it to decapped Berdan cases (ex-Cordite) which have also been neck and shoulder annealed; here the failure rate is about 5%.