Amidst other projects, I am working on a .357 Magnum double rifle. The barrels will be roughly 20" long, as dictated by the barrel blanks to hand, and the chambering will be .357 Magnum/Maximum. I am definitely going to use the magnum chambering-but I am contemplating the idea of going ahead and setting up for the Maximum, as it's a simple re-ream touch up later to do.

The issue is regulation!

I need to decide what kind of loads I want to use with the gun, as part of the design, not part of the fitting and finish. The barrel twist is 1 in 16" and should shoot 200gn round nose bullets fine.

I am thinking that I should work around a loading of 1500-1800fps and a 180gr bullet, this is a fairly easy to get factory offerings and pretty easy to obtain from a rifle-length barrel.

But if I later rework the barrels to accept .357 Maximum length cases, I would have to either re-regulate, or work up a load that does good enough. Not having worked with the Max, I don't know if it's a big enough improvement to be worth the effort-anyone have any thoughts on the matter?

I have a contender carbine 16 inch in 357 Max.

The Max well give you a couple hundred FPS over the mag or a bit more.

I get 2150 with a 158gr JSP.

It well not shoot well at all using 357 mag casings. group sizes easily double.

Personally I would just make a max if your going to end up there any way.

You might get 1500 in the 357 mag you most likely well not get 1800 I get 1850 out of my 18 inch 357 mag carbine with a max load. and a 158gr.

I gain very little out of my 22 inch 357 mag over the 18 inch one.

I know what the books say but I have been very disappointed with actual velocities of the heavier bullets.

I use the 180s unless you want to use rifle bullets.

I cast a bunch of 200gr bullets trying to work up a suitable heavy bullet bear self-defense load the velocities were miserable. In both the revolvers and the carbines.

The 18 inch marlin shot nice groups with them the 22 inch Rossi would not stabilize them.

800 to 1200, 1200 out of the carbines with any of the powders I tried. The best I could get out of 6 inch 686 was 950.

Wolfram,
You are right; you DO need to decide on the planned load before you proceed with your project.

This will be easy if you have a firm idea of how the rifle will be used.
Will it be plinking and casual target shooting? If so, light 110 and 125 loads may be best.
Will it be for hunting and if so, what game? Let the game dictate the choice of ammo?
Will it be self defense and if so, from what? Let the threat dictate the choice of ammo.

Also, do you plan on being able to sell the rifle? If so, plan to use commercially available ammo.

Pdogshooter has extensive experience with the .357 caliber and is correct when he suggests deciding on making the rifle in either .357 Mag or .357 Max NOW and make it that way from the start.

I also like the .357 Mag and have shot it in pistol and rifle (1892 with 20 inch barrel) for many years. It is fun to shoot and has many uses, including training youngsters to shoot a center fire rifle.
Enjoy your project and please report how it goes.

My brother had a Ruger No3 in 357 Mag that he reamed to Max. It approximated velocities of 35 Rem. He also shot 358 bullets in it as I did when hunting with my DW 357 Super Mag revolver.
Good cartridge.

If your action is strong enough for it (basically 223 strength and 60kpsi) you can easily get 2150fps with a 180gr and a 16" barrel or a little over 2200fps with a 20" barrel going with 357Max.

quote:

The Max well give you a couple hundred FPS over the mag or a bit more.I get 2150 with a 158gr JSP.

Not to hijack Wolf's thread, but what powder do you have behind that bullet PDS?

I found H110 to give me the best velocities.

I found W296 (same thing as H110 now) gives the best speed followed by LilGun which comes close. IMR4227 and 2400 which are both a little slower and have used a couple others with cast bullets.

My go to for .357 Mag in my Blackhawk is 2400. Curious as to its use in the Max. I would think slower would be better with a 17+" barrel.

The purpose for the rifle is primarily learning to build the thing and make it look "right", feel "right", and function "right". Part of that is "fit for purpose", and so here are the goals:

CXP2 class game (100 to 300lb non-dangerous)
75 yard regulation point (50 to 150 yd effective range)
20" barrel length
Express sights with two leaves
35 caliber rimmed cartridge

I am open to input on all aspects at this stage of the game.

Farthest shot we've taken on a deer with a 357Max was 142 yards (rangefinder) which broke the opposite shoulder on the way out. 180gr SSP Hornady at 2150 fps. Take a look at the RCBS 35-200-FN mold. You can throat it longer to seat the bullet out further to gain case capacity, but 2000fps should be easily "do"able with your 20" barrel. My plinker loads with it are over 1900fps out of a 16" barrel.

I own two 357 rem max carbines and a Dan wesson 357 ,max pistol .It's an awesome little cartridge and works awesome just wish I had a lever action in it .Mine shoot 357 mag just fine also .My best powder is aa1680 which gets the most out of the case size .You.Will have a blast shooting it too ! I don't regret at all getting my two carbines !

How about 35-30?

You might also consider the .357 Herrett.

I have a 357 Max G2 Contender (12" barrel) and a 357 Max Ruger Blackhawk (10" barrel). I have had had a H&R with a 22" barrel in the past but it is now gone. I would love a lever carbine converted to the Max but so far it has seemed to much effort to do as it requires making new parts.

I shoot 180 grain bullets in them almost exclusively. For what it is worth, the powders that chrono the highest while still producing good accuracy for me are: Accurate 1680 and Hodgdon Lil'Gun for the Contender and Hodgdon H110/Win 296 is the powder in the Blackhawk.

If I had a 20" barrel I would look start with AA-1680. Look at the Accurate/Western Powder manual for loads both at SAMMI COAL and over SAMMI COAL.

Final notes:

Make sure you crimp well with this cartridge. It helps with consistent ignition and lowering SD on velocities. If the bullet has a cannalure you can use a standard roll crimp, but without a cannalure you need to get a taper crimp die. When people can't get the groups that the Max can deliver, crimp/neck tension and COAL are the two things I suggest.

Also look at the Hornady dies for loading the Max. You can easily add their FTX insert for pointy bullets and add their micrometer dial for adjusting COAL precisely. That sliding bullet guide makes things nicer too...it isn't a Forster Ultra or Redding Competition, but neither company makes a premium seater in Max.