303 British to 410 shotshell

[cwtebay]

I don't understand your hunting Elk from horseback with a .410? as for full mail box -check both recieved and sent -they both count.

In weapons restricted areas you can use a shotgun. There is no restriction on hunting or firing from horseback as long as you observe the restrictions for weapon as well as other pertinent game laws.

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[Owen49]

Has anyone tried 9.3 x 72R brass? I've not had any luck finding 9.3 x 74R but found some of the 72R.

[G.O. West]

Fireforming the 303 British case results in a 1/8" longer case than mechanically expanding it. A previously fired case needs to be annealed to avoid split necks. You often need to remove .005" from the case head to reduce rim thickness. If you use a home made plastic shot capsule as described in the link below, you can load any recommended weight of shot.
https://thefiringline.com/forums/sho...ght=303+to+410

[Quinnbrian]

Can be done but 444 Marlin is much easier
Mike

Yes I've used 444 Marlin brass before,with great Results.

[cwlongshot]

Yes I've used 444 Marlin brass before,with great Results.

But know, NOT all guns will properly function with 444 cases. The rim dimentions are not as full as 303 or 9.3 cases.

[lar45]

https://www.youtube.com/watch?v=vwV0WYn52Ik
This how I fireform 30-30 to 375 Win.
It should be doable for 303 to 410 also.

My guess is you are going to load a nice heavy slug loaded in converted brass.
Get close and slip one in behind the shoulder. Should do the job.
What about using a hollow base 458-405. Then size it down to fit your brass and chamber.
The hollow base will expand to seal and maybe give better accuracy and velocity?

The hardest part is getting close. Maybe the Horse will help with that?

We need pictures of your gun and brass forming operation.