Resizing 357 Maximum for 357 magnum shot loads.

[sniper]

What can be used to resize the mouths of 357 Max brass so they will fit the 357 magnum cylinder? A 9mm Lee Factory crimp die? Lee bullet sizing die, .356? A 9mm size die?

[BK7saum]

i don't exactly remember what I used. I am sure I posted it in my thread from a year or two ago, but I think it may have been a Lee or NOE bullet sizing die around .356 to .360"

[BK7saum]

https://castboolits.gunloads.com/sho...K7saum+rem+max

[rockrat]

MIght have used a 38 special crimp die or 9mm crimp die

[jcren]

Not sure on 357 mag, but I used a 327 mag sizing die to "shoulder" some cut 223 brass to make 380 acp shotshells that were the same oal as a conventional load. Worked better than expected.

[BK7saum]

I did use a 327/32 seater die (0.330") to create the "neck" on the maximum brass.

For some reason, probably because the case isn't supported, the "neck" did not form concentric to the body with the 0.356 die. It needed a smaller constriction in order to fit in the chamber.

[Rapier]

Just trim to 357 mag trim to length and reload using 357 Mag dies. They are the same case just a bit longer on the Super Mag (Max).

[BK7saum]

Just trim to 357 mag trim to length and reload using 357 Mag dies. They are the same case just a bit longer on the Super Mag (Max).

The OP is attempting to load shotshells that are the full chamber length, not just loading 357 magnum cartridges.

[trapper9260]

The OP is attempting to load shotshells that are the full chamber length, not just loading 357 magnum cartridges.

The way it sounds then , just have the case full length of the cylinder and then load . Might need some adjustments for how it sounds. I am not sure I have not done it yet. But give me a idea to work on this winter.

[psweigle]

Back when I looked into doing this, there was a die to star crimp "blanks". That was the route I was going to go.

[Alferd Packer]

Star crimp ruins cases

[Meatpuppet]

I don't know your circumstance, but it may be worth going in another direction for a dedicated "Snake/Rat Gun." The Bond Arms "Roughneck" Derringer in .357 can be had for as low as $250. Ream it out with a 357 Max reamer and you have a pretty lightweight little snake gun that is easy to reload for and does not wreck the brass. I did the same to a Bond Arms 45 Long Colt and had it cut with a 460 S&W reamer. Still working up shot loads for it, but it holds way more #11 shot than a .410 shell does. Who knew that Harvester Muzzleloader 45cal Hi-pressure Sabots make excellent shot cups?

The bonus is that the barrels are relatively cheap and you can easily convert it back.

[uscra112]

I keep seeing this thread and shaking my head. Necking down a Maximum case so it fits into the throat of a .357 Magnum cylinder means you're going to be driving your shot load through a funnel. Am I missing something?

[trapper9260]

I keep seeing this thread and shaking my head. Necking down a Maximum case so it fits into the throat of a .357 Magnum cylinder means you're going to be driving your shot load through a funnel. Am I missing something?

You have a good point there, one thing I did not think of and it is a thing that I think should not do, funnel the shot . What dose others think ?

[BK7saum]

No one has a full choke barrel on there shotgun?

I agree not an ideal situation, but is it really a problem. I am sure there will be deformation of the shot from the transition but i am only lookig for 800-900 fps out of #12 or dust, not a super handicap trap load of 7½s at 1330 fps.

[uscra112]

Full choke doesn't reduce bore area by 14%, and the choke is at the end of the barrel, not at the throat.

Restriction like that is going to boost pressure by quite a lot. It's not like pushing gases through the neck of a shouldered rifle case, you're asking a charge of lead shot to crowd through.

How are you going to get wads past that reduced diameter without damage?

[high standard 40]

The 45ACP shot loads that many of us load utilize a shouldered case without any problems. I don't see this as being any different. I also have some longer, shouldered case shot loads for my 44 Mag revolver. Again, I haven't seen any problems. The pressures I use for shot loads are by necessity low or patterns suffer. I'm not advising anyone to follow this path, though. We can each decide what we are willing to load.

[uscra112]

Well, I'm open to empirical evidence, but it seems mighty counter-intuitive to me.

[BK7saum]

Wads are disc of manila folder or a disc of primer cardboard. So getting the "wad" through the constriction isn't a problem. Just insert the disc sideways with a slight bend, push in, then tamp / flatten the wad on top of the powder.

Shooting higher velocities/ pressures is counterproductive to even groups. While the constriction boosts pressure, the pressures arent on the high end anyway.

[triggerhappy243]

i make shotshells for my 44 mag, that the brass is full cylinder length, and have no issues. 150 gr. load of #8 or #9, 9.5 gr. of unique. good enough for snakes at 10 foot away. I convert 303 brit brass.