Rechamber .357 Magnum to .357 Maximum

[rickhem]

Can a Henry in .357 magnum be rechambered, or have the existing chamber extended, to .357 maximum?

I've done a few searches and haven't seen this asked before, which I find kind of surprising. The SAAMI spec for .357 magnum is 35,000psi, while the .357 maximum is 40,000psi, so there is that 5,000psi difference to consider. But a rifle should be able to really make use of that larger case and increased powder capacity. The 30-30 is 42,000psi, and a .44 magnum is 36,000 psi, so this seems do-able to me.

Has anyone done this, or talked to Henry about it?

[clovishound]

I did a quick internet search and found a number of discussions on a variety of difference forums.

Here is one:

https://savage24forum.boards.net/thread ... ag-maximum

Here is the first page of the search I did. Most of the relevant links were further down the page, rather than the first few.

https://www.bing.com/search?q=can+a+.35 ... cc=0&ghpl=

[North Country Gal]

Mike Bellm's has done Contender 357 barrels to Max for me. The increase in pressure is no big deal. If you're talking about Henry lever guns, though, one issue might be the cartridge length increase for the Max as far as feeding and cycling. And, of course, don't expect to find factory Max ammo. Definitely a reloader's cartridge, now.

[BigAl52]

Mike has done work for me as well. He does chamber the Henry Single Shot to 357max. But Like NCG says Im not sure the Henry levers will cycle the longer max. But I bet if you call Mike he can give you that info. Mike knows the 357 max very well.

[rickhem]

It may not have been clear in my original post, but I'm aware that this is a fairly common modification in Contenders, and some single barrel rifles, including the Henrys, but I was wondering about the lever guns.

I have a .357 Big Boy Steel, with sidegate, and a 20" barrel. Externally, these models all have similar dimensions, meaning that a .44 or a .45 having the same barrel/chamber OD as my .357, would have less steel due to that bigger bore on the larger chamberings.

Not really looking to send anything out just now, but it's another idea floating around in my head and I was wondering if anyone has done this. As was mentioned, the longer cartridge, depending upon what projectile is selected, would possibly complicate feeding.