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458 Win mag shotgun?

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25 February 2002, 10:47
frankg
458 Win mag shotgun?
This is just an idea I'm bouncing around but I was wondering if this is possible. What I'm thinking is a .458 Win mag bolt gun that has been fitted with a smooth bore barrel.
The advantage to this is that the straight walled cases could be loaded with bird shot for use like a shotgun. The very strong case would allow the shotgun shells to be loaded much hotter than a normal shotgun, possibly increasing range if the group would hold together. And regular bullets could also be carried for bigger game. Of course accuracy would probably not be good so shots would need to be close.
The closest thing I know of to this combo, is of course the .410 shotgun. The 458 shotgun would out perform it in every area. Especially when considering the the slow 100gr .410 slug.
If I could get the components this might make a way cool gun to have. And it would be interesting to see what a super fast load of #4 birdshot would do to game birds.
26 February 2002, 11:37
<Fat Bastard>
Disclaimer: this is total conjecture on my part.

Is it possible? Sure. It probably wouldn't work.

1. I think it's universally agreed that excessive velocity ruins shotgun patterns, probably due to increased accelerative forces distorting the shot, muzzle blast blowing the pattern apart, etc. A super-hot load would just make things worse.

2. Crimp - how would you crimp? You'd have to go (back) to the old-style roll crimp with a card over the shot. These make your patterns worse, too.

3. The cross-sectional area of a 12 gauge (.73") is .419 sq. in. Cross-section of a .458" bore is .165 sq. in. - 40% of the 12 gauge. Since the case length is approximately the same, you'll only have 40% of the payload. Unless you want to go with a thin wad, but then you'll get more distortion of your shot (see #1), more recoil, etc.

4. Feeding - I picture the roll-crimped, square-ended rounds hitting the front of the magazine box and stopping. Lots of mod work to do there, I'd guess.

As for what a super fast load would do to a game bird, shoot a quail at 10 yards with a garden-variety light game load and see what happens. No need to mess around with a meat grinder.

But hey - if you like to tinker, do it and let us know how it works out. I'd be interested.

26 February 2002, 14:09
frankg
Unfortunately I think you are right. I think my biggest problem is going to be the velocity destroying the groups.There may not be any way to stop that.
But I have found a way to tinker for less money. I am going to creat .410 shotgun shells from rifle shells. They are already started. A guy I know is making them for me from 9.3 x 74. (I think, can't remember off the top of my head)We ran the numbers and the match is perfect. I'll put these in a bolt rifle action with a strong shotgun barrel. You get the idea. Then I can compare the groups to normal .410 shells as I bring up the speed and watch for signs of pressure. I believe the brass/gun combination will be so strong that I will never get into pressure, but that has yet to be seen. I'll let you know.

26 February 2002, 17:25
Atkinson
FrankG,
Brass shot shells are older than paper shotshells, what you are wanting to do is not a problem at all and it will work, its allready been done..

My questions is "Don't you think you need to get an extra job to keep you a little busier"

------------------
Ray Atkinson

ray@atkinsonhunting.com
atkinsonhunting.com