Questions about 357 MAX

[andym79]

Hi guys, as you might have read from my other post I am considering a multitude of possibilities for a Martini Cadet build.

One of my favorite ideas at the moment is to have it chambered in 357 MAX.

My gunsmith says he can do it and that the 357 max will work okay.

I have some questions however, firstly I have read that if a standard reamer is used that the 357 max has a horrible throat that is not cast friendly.

Second, my smith makes some good barrels, but only offers 358 barrels in 1:12, whilst that might be a good twist for stabilizing heavier bullets, am I right in assuming that its a bit fast if you want to drive cast hard? I would rather use him as he does a good job, but I don't want to lock into a twist that may not be best.

Thirdly, if I wanted to shot big bullets a slowish how heavy can you go in a 357 max with a 1:12 twist?

What advantage has the max over the mag, any if you want to shoot cast at moderate velocity?

[Tatume]

The problem of chambers is the difference between a rifle chamber and a revolver chamber. Revolver chambers for the Max have a section in which the bullet is not positively guided. Rifle chambers have a definitive throat which is cut to groove diameter, or 0.358 inch. This holds the bullet in alignment from the time it begins moving until enters the rifling. Sometimes it is necessary to cut the throat as a separate operation, as opposed to using a reamer ground to cut the chamber and throat at the same time.

In revolvers it was found that light bullets caused unusual flame cutting of the top strap. Heavy bullets did not. In a single shot gun like the Martini or T/C Contender this is not an issue, and the Max can be used with light bullets for varmint hunting of just plain fun. Personally, I have never found "over stabilization" to be an accuracy issue with sporting arms. My bench rest guns are barreled with carefully chosen twist rates, but the difference is lost in the noise in a sporting gun.

Take care, Tom

[andym79]

Thanks for that Tom.

How large a bullet can you shoot in the 357 max? Would 250 grain be too much, would a 180-215 grain be a sensible choice?

[725]

Lots of folks have good luck with 180 grain bullets.

[rockrat]

I have shot a 270gr boolit from an Old West mould that shot very well in my Max. Don't remember the velocity though

[Tatume]

Typically I shoot 180 and 200 grain bullets in the 357 Maximum. I think the 180 grain bullets are probably more effective, but haven't done any definitive tests.

[ubetcha]

I'm sure you may have seen this mentioned before, but to get a real good feel for the problems or potentials and tricks of the 357Max, go to Mike Bellm's web site. The 357 Max is his favorite caliper and he has done quite a bit of work with it. www.bellmtcs.com. I understand that when Elgin Gates developed the caliper, it was designed to shoot 170 to 200gr bullets and was meant to be able to knock down the 200 meter rams in IHMSA silhouette competition for the 357 caliper. It does that quite well and has proven to be a very effective hunting round also. Can be used as a plinker with light bullets and low powder charges. As I understand, the flame cutting in the revolvers came from people trying to drive light bullets very fast with ball powders and the very hot flame and unburnt powder would blast through the cylinder gap and flame cut the top strap. Although the flame cutting would stop once it reached a certain depth, the manufacturing of the caliper in a revolver stopped. Many feel the depth of the flame cut would not hurt the function of the revolver. In a couple of Lyman cast bullet books that have the Max listed, the fps listed are 1400> with 180-200gr bullets. I have a G2 with a 12" bbl rechambered to 357Max by Mike, and to me, the recoil is very manageable with the 180-200gr weight bullets

[NSB]

I have a Browning/Miroku Low Wall in 357max. It started life as a 357mag, but was never shot that way. As a new gun it had the chamber lengthened and has been shot that way since. I have a pretty full spread sheet for that gun listing every bullet tried along with every powder and primer I could get my hands on. It shoots 180g bullet very well, but shoots the 158g even better. In fact, it shoots them the best. The bullets I tried out of my gun in weight ranges over 200g didn't shoot as well. That's probably my gun, not all guns. I've shot several deer with the gun at ranges up to 130 yards and have always gotten pass throughs on the 180g and mostly pass throughs on the 158g. What stops pass throughs on the 158g is that the most accurate bullet I've found for it is the Nosler pistol bullet which is a jacketed hollow point. The damage to the tissue is awesome with this bullet. I reserve all shots for lung shots only using that bullet. I do believe the 180g is a better deer bullet though since it shoots nearly as well and always passes through. I've shot two and a half inch groups with it at 200yds off the bench.....that's a five shot group. There was a good cross wind which opened it up horizontally. Interestingly, there are a good number of powders that perform very well in this gun so it's never a problem finding powder to use.

[calaloo]

Something that no one has mentioned is that the length of the straight sided .357 Max cartridge precludes its chambering in the Cadet. I have one myself and a Max case will not "make the turn". I recently built a .357 smoothbore on a Cadet action and chambered it to the Max length. I relieved the top of the chamber and still have to trim a few thousands off the brass before it will chamber. And that is just a case without a bullet. I have heard that some will work but my experience belies that. If I were you, and were bound and determined to chamber one for the Max cartridge, I would fit a barrel stub chambered for the Max and see for myself.

[fatelvis]

I've gotten great accuracy in both my Dan Wesson and my Bellm chambered 12" G2 Contender, using a Lyman 357627 boolit over a stiff charge of IMR4227, and sparked off with a Rem 7 1/2 primer.

[runfiverun]

I have shot the 250's in my Max revolver. [actually the only cast I have shot in it]
and many 35 cal rifles use the 12 twist.

you might want to look at the .360 Wesson round it's right in between the max and the mag.
plus you can actually buy brass from Star-line instead of looking for Remington brass for the next 6-9 months.

[quilbilly]

That 200 gr RFGC boolit from Lee shoots very well in my Max carbine at about 1700 FPS with 2400 as does the 170 Gr SWC from Lyman at about 1350 FPS with Unique. As a plinker, the Lee 150 gr RN shot well for me at 1200 FPS with Unique. Until I started using that 200 gr boolit, I was shooting the 158 gr SWC-GC at 1850 fps with 2400 giving consistent 2 MOA accuracy but was concerned it might be a bit light for black bear. Terminal ballistics tests with the 200 gr showed it was a vastly superior performer. None of the above are hot loads. If I was still hunting elk, that 200 gr boolit at that velocity cast from the right alloy would be an option at ranges under 75 yards but I have a 444 for that.

[P Flados]

With a rifle, I would feel cheated if I had to stay with 357 magnums.

A pretty big jump in performance is available by going with a 360 Dan Wesson chamber. You get a little more case capacity, but you get the ability to load rounds that are above today's reduced 357 magnum pressure limit without any risk that one of your loads end up in the wrong (light weight) guns that were never really strong enough for the original allowed pressure. Also, with a 360 DW chamber, you can load a heavy boolit in a magnum case with it much further out than allowed by the book OAL of the magnum (the short allowance for the exposed portion of the bullet is another performance robbing feature of the 357 magnum).

Going from a 360 DW to a 357 Max does give you the ability to get closer to 35 Remington performance. Is this what you really want. There is a pretty big increase in case length. If you do more than a little low power shooting, and if you really do not need the extra top end performance, the 360 DW may actually be a better choice.

Star line is now a source for both the 360 DW and the 357 Max. Until recently, 357 Max case availability was a notable concern. Now you should be able to get what you need as long as you have the $$$.

[andym79]

Something that no one has mentioned is that the length of the straight sided .357 Max cartridge precludes its chambering in the Cadet. I have one myself and a Max case will not "make the turn". I recently built a .357 smoothbore on a Cadet action and chambered it to the Max length. I relieved the top of the chamber and still have to trim a few thousands off the brass before it will chamber. And that is just a case without a bullet. I have heard that some will work but my experience belies that. If I were you, and were bound and determined to chamber one for the Max cartridge, I would fit a barrel stub chambered for the Max and see for myself.
Can anyone comment on this, my gunsmith said he can do it and only needs to shave a sliver off the breech block!

[andym79]

I have shot the 250's in my Max revolver. [actually the only cast I have shot in it]
and many 35 cal rifles use the 12 twist.

you might want to look at the .360 Wesson round it's right in between the max and the mag.
plus you can actually buy brass from Star-line instead of looking for Remington brass for the next 6-9 months.

It maybe so in the states but 360 wesson brass is even more rare than 357 max brass here in AUS! I would probably need to make it from 357 max or 5.6x50r if I couldn't find any more 357 max (I managed to get from an acquaintance 100 secondhand 357 max cases).

[andym79]

With a rifle, I would feel cheated if I had to stay with 357 magnums.

A pretty big jump in performance is available by going with a 360 Dan Wesson chamber. You get a little more case capacity, but you get the ability to load rounds that are above today's reduced 357 magnum pressure limit without any risk that one of your loads end up in the wrong (light weight) guns that were never really strong enough for the original allowed pressure. Also, with a 360 DW chamber, you can load a heavy boolit in a magnum case with it much further out than allowed by the book OAL of the magnum (the short allowance for the exposed portion of the bullet is another performance robbing feature of the 357 magnum).

Going from a 360 DW to a 357 Max does give you the ability to get closer to 35 Remington performance. Is this what you really want. There is a pretty big increase in case length. If you do more than a little low power shooting, and if you really do not need the extra top end performance, the 360 DW may actually be a better choice.

Star line is now a source for both the 360 DW and the 357 Max. Until recently, 357 Max case availability was a notable concern. Now you should be able to get what you need as long as you have the $$$.

I am not really interested in getting close to 35 rem performance, I have a 375 W BB and I would make up a 356W on that action if I really wanted to outperform the 35 rem. To be honest if I was going for that I would probably go for a 35-30/30 as I would have a good source of brass.

The 360 wesson would probably be closer to what I want and probably work better in the cadet, possibly without any modification.

[calaloo]

I should add that there is not much metal between the channel and the hole for the striker in the block. Removing metal there will substantially weaken the block. Go over to the ASSRA forum and pose your question. The membership there are very knowledgeable about all things single shot.

[ubetcha]

Another thought is making a 357Max rimless using 223 brass. I'm not familiar with the Martini action, so I don't know is a rimless version is possible. I f the Max case length is to long, maybe a 360DW rimless version would be possible as the 360DW is right between the 357mag and the 357 max in length

[rosewood]

I have a 12" contender in .357 mag. The lead is ridiculously long and I am able to seat the lee 200 grain boolit longer than listed Dan Wesson OAL. My OAL is 1.800". My boolit is dropping at 206 grains with the gas check and I am getting 1580 out of that 12" barrel and it still seems to be running low on the pressure side.

I purchased some Dan Wesson brass, but the chamber isn't quite deep enough for the brass to chamber. So I would either have to trim the brass back a bit or ream it to fit. If I was going to ream, might as well go to max. I have considered reaming to Max, but don't want to change the barrel from factory. Since I am getting such good velocity and accuracy, I have elected to stick with the seated long boolit in the mag brass.

Rosewood

[P Flados]

Interesting that 360 DW rimless was mentioned.

I have played around with making rimless 357 maximum cases from 223 brass and found them to be a real pain.

Making up 360 DW length rimless is however a piece of cake.

If you are willing to to deal with case mouth head spacing, the advantages are notable.

Probably no reason for a custom reamer. A 380, 9 mm, 38 super or similar reamer can probably be used to deepen a 357 mag chamber and give it the little sharp step needed for case mouth head spacing.

For a contender, a 221, 222, 223 etc. extractor is easy to install.

Rimless extractors for most other candidate guns are also not too much trouble.

Brass is free at best or dirt cheap if not free. As previously discussed, brass conversion real easy. It is just cut, trim and run them run through some dies. I know 357 dies with a 223 shell holder work. A set of 9mm or 38 super dies probably should also.

[ubetcha]

Interesting that 360 DW rimless was mentioned.

I have played around with making rimless 357 maximum cases from 223 brass and found them to be a real pain.

Making up 360 DW length rimless is however a piece of cake.

If you are willing to to deal with case mouth head spacing, the advantages are notable.

Probably no reason for a custom reamer. A 380, 9 mm, 38 super or similar reamer can probably be used to deepen a 357 mag chamber and give it the little sharp step needed for case mouth head spacing.

For a contender, a 221, 222, 223 etc. extractor is easy to install.

Rimless extractors for most other candidate guns are also not too much trouble.

Brass is free at best or dirt cheap if not free. As previously discussed, brass conversion real easy. It is just cut, trim and run them run through some dies. I know 357 dies with a 223 shell holder work. A set of 9mm or 38 super dies probably should also.

Not to steal the post, but can you give use some info as to how to make the 369DW rimless.Especially on how you expand the case.

[Moleman-]

Since rimless 357max from 223 cases was mentioned, here's how I make them for a few 357 max rimless ar15's we have. http://castboolits.gunloads.com/showthread.php?312306-357AR-(Max-Rimless)-from-223-5-56-cases Since it's shorter making DW cases would be a little easier as none of the neck would be used.

[P Flados]

I also made up & used some rimless maximum rounds. I made up some at 357 maximum length and some just a little bit longer (enough to push up against the taper at the end of my contender maximum chamber). I did this as I was not sure the 222 extractor would be good enough for reliable head spacing. The cases seemed to work pretty good, but they were something of a pain to make.

After my previous post I went back & made a test run of a hand full of 360 length cases. Once I started, it did not take me long to work "good" system.

Put a 223 case in my cordless drill.
Spin the case with the drill and use a tubing cutter to cut it at the shoulder to body junction.
Spin the case with the drill and insert a tapered object (needle nose pliers) to remove the rolled in portion and flare the end
Run the case into a 357 magnum expander die
Trim the case to final length + 0.010".
Run the case in a 357 magnum sizer die
Do a final trim to desired case length
Do a final pass through the expander die and it is ready to load.

The photo to the left shows a left to right progression for making 360 cases, the one on the right compares the various cartridges being discussed.

178981178982

I am pretty confident that these cases would function as good or better than 357 magnum brass for full power loads.

Just to actually confirm how well it will work, I am pondering my choices for converting my 8.75" Contender 357 magnum barrel.

I do not want to mess with a custom reamer, and do not even want to go bug the local gun smiths to find out if they have anything that would work.

If I was slow, patient and careful, I know I could fab up one reamer to cut a throat and lead region like I want and I could fab up another to extend the 0.380" portion of the chamber.

I am just a little hesitant given the following

Quite a bit of work
A small risk of not getting my desired results for chamber cutting
I really do not have any need for a 360
The new chamber may not like 38 specials (it is currently my best barrel for 38s).

The last item above is probably the biggest of the bunch.