357 Maximum data vs 350 Legend data

[Timmis2]

I've heard a few 350 Legend reloaders say that 357 Maximum data can be used for 350 Legend load development due to their similarities in projectiles, case size and capacity, bore size..etc. Hodgdon published load data for the 357 Max and 350 Legend use 9 of the same powders. The 357 Max SAAMI spec is rated for lower maximum PSI than 350 Legend therefore 357 Max is loaded with fewer grains of powder for most loads. 357 Max data is published as a handgun cartridge whereas 350 Legend is published as a rifle cartridge, however there are 357 Max rifles using 357 Max pistol ammo, and there are 350 Legend revolvers using 350 Legend rifle ammo. Hodgdon used a 10 inch handgun barrel for 357 Max data, and a 16 inch rifle barrel for 350 Legend.

350 Legend max pressure: 55,000psi
357 Maximum max pressure: 40,000psi

350 Legend case length and capacity - 1.71 inches/36.5 grains (water)
357 Maximum case length capacity - 1.6 inches/34 grains (water)

.355 projectile weights in Hodgdon data for 350 Legend - 115gr to 250gr
.357 projectile weights in Hodgdon data for 357 Max - 100gr to 200gr


One standout difference in Hodgdon data between the two cartridges is....357 Max has loads using Longshot and 572 powder that use less than 10 grains as a minimum charge, with velocities slightly below subsonic or just above subsonic using projectiles from 140gr to 180gr. Hodgdon has no data for 350 Legend using Longshot or 572. If you want to shoot 350 Legend subsonic (or close to it) there is only a single 250gr bullet with 14-20 grains of various rifle powders that aren't published for use with any other size bullet for 350 Legend.

Both Longshot and 572 are shotshell powders but also have lots of data for pistol cartridges. LS and 572 have fast burn rates and are higher up on the burn rate chart than all other powders in the data for both 357M or 350L. Just 11 grains of LS or 572 with 357 Max yields nearly the same pressure as 20+ grains of all other powders published for 357 Max, which are all rifle powders. While Longshot and 572 are marketed as shotshell powders, there is more published load data for them for pistols than there are for shotshells.

Most published loads for 350 Legend are for velocities above 2000 FPS beginning with about 24 grains of rifle powders. That's to be expected. 350 Legend is a cartridge designed for bolt-action rifles used by hunters in states with straight wall cartridge laws. There is no urgency for Hodgdon to test and publish alternate loads and subsonics for all. AR15 owners with 350 Legend uppers do not have factory ammo or published loads specific for their needs and are left to extrapolate what they can from the data and discussions there are. 350 Legend is a newer cartridge and hopefully more data and ammo will come.

If there is a good argument that 357 Max data can be used in 350 Legend load development with respect to 357 Max's lower pressure rating and 350 Legend's longer barrel, then can 350 Legend also use Longshot and 572 with similar powder charges and bullet weights as 357 Max data? This would be a good option for 350 Legend as an economical load using half as much powder as most other published loads, and using more choices of projectiles at acceptable velocities for things like plinking and varmint hunting. The longer rifle barrel of the 350 Legend may produce higher velocity than the same load in the 357 Max barrel, and that's okay. Longer barrels don't produce more pressure than shorter barrels.

Just because 357 Max has Hodgdon data using Longshot and 572 doesn't mean it's a great performing load for 357 Max or 350 Legend. 9-11 grains of Longshot and 572 uses less than 50% of the case capacity for both the 357 Max and 350 Legend case, and I haven't seen any reports that Longshot or 572 are okay with position sensitivity or low case capacity, but I think it might be worth testing in 350 Legend if the data can be used as a means to develop an economical load for 350 Legend. If Longshot and 572 doesn't workout for 350 Legend, they will workout for the pistol loads Hodgdon has data for.

If you have Quickload, maybe you could run the numbers to help figure this out. (I don't have the operating system required of QL). If you have experience using 357 Max data to develop 350 Legend loads, please share your experience.

Have a great day!

 

[SeabeeKen]

After extensive testing in a friends 350L bolt rifle, I can say I found superb accuracy with a couple powders and bullets. For one example, A 125 Maker bullet with Alliant 2400 powder shot .037" @ 100 and was also consistently ringing 6" steel at 300.
I dont bother with subsonic loads in anything.
You dont say which OS you have but GRT has versions for Windows and Linux. A windows partition can be setup on Apple machines to operate QL or GRT.

 

[Timmis2]

After extensive testing in a friends 350L bolt rifle, I can say I found superb accuracy with a couple powders and bullets. For one example, A 125 Maker bullet with Alliant 2400 powder shot .037" @ 100 and was also consistently ringing 6" steel at 300.
I dont bother with subsonic loads in anything.
You dont say which OS you have but GRT has versions for Windows and Linux. A windows partition can be setup on Apple machines to operate QL or GRT.

I use a Chromebook and can't run Quickload or GRT. I should have mentioned too, I don't have an AR15 with a 350 Legend upper. I have a bolt-action rifle in 350 Legend. I am not concerned with 350 Legend loads cycling a semi-auto action.

 

[dhagerty40]

I would take that with a grain of salt.
First my guns (both are 10" handguns) have a 357 Supermag chamber and not a Maximum chamber. The only difference is that the supermag case is .010" longer. Also, The max pressure on the original supermag was 50,000 Psi.

Now, The load I shoot in the 357SM is: a RCBS 35-200gr FN cast bullet, 19.0 grs of H4227 and RP 71/2 primer. it chrono's at 1587 fps.

And I ran it through Quickload and why I say do not bother (both checked at a 10" barrel):

The above load shows in the 357 Max at 1565 fps at a pressure of 42,000 psi.

the same above load in the 350 Legend shows at 1377 fps at a pressure of less than 24,000 psi
checking at 22" barrel increased speed to 1638 fps.

in other words, A big difference.....

I hope this is what you were looking for..

 

[Timmis2]

I would take that with a grain of salt.
First my guns (both are 10" handguns) have a 357 Supermag chamber and not a Maximum chamber. The only difference is that the supermag case is .010" longer. Also, The max pressure on the original supermag was 50,000 Psi.

Now, The load I shoot in the 357SM is: a RCBS 35-200gr FN cast bullet, 19.0 grs of H4227 and RP 71/2 primer. it chrono's at 1587 fps.

And I ran it through Quickload and why I say do not bother (both checked at a 10" barrel):

The above load shows in the 357 Max at 1565 fps at a pressure of 42,000 psi.

the same above load in the 350 Legend shows at 1377 fps at a pressure of less than 24,000 psi
checking at 22" barrel increased speed to 1638 fps.

in other words, A big difference.....

I hope this is what you were looking for..

I wouldn't think the pressure would be so much less in 350 Legend for the same load in your 357 Supermag or the 357 Max data. Can you speculate why that may be? The 350 Legend case is not much bigger than 357 Max to cause that much difference in pressure in the same load. Perhaps QL accounts/predicts for other factors?

 

[dhagerty40]

I wouldn't think the pressure would be so much less in 350 Legend for the same load in your 357 Supermag or the 357 Max data. Can you speculate why that may be? The 350 Legend case is not much bigger than 357 Max to cause that much difference in pressure in the same load. Perhaps QL accounts/predicts for other factors?

The difference is in the case...

The 357 Max is a straight wall case and measures at .379" both at the mouth and the bottom of the case

The 350 Legend is a slight tapered case and measures .379" at the mouth and .393" at the bottom of the case. Yes, The case is only .1" longer though. Also the reason you show about 2.5 grs more capacity with water.

Checking, My load shows a loading density of 108% in the 357 Max. The loading density with same charge in the 350 Legend is only showing 81%.

Actually also, The case capacity shows in Quickload at 33.60 grs of water with the 357 Max. it shows at 36.80 grs of water for the 350 Legend.

 

[tommeboy]

When the 350l first came out we used 357max load data. So yes you can use it for the 350l. Might not work for your ar15 but it will for a bolt gun. Stay away from lilgun. It is way too temperamental for the 350l. What looks like a safe load will blow the primers out 2 hours from when you just shot them. And make sure to use a mag primer with any ball powder.

 

[Timmis2]

The difference is in the case...

The 357 Max is a straight wall case and measures at .379" both at the mouth and the bottom of the case

The 350 Legend is a slight tapered case and measures .379" at the mouth and .393" at the bottom of the case. Yes, The case is only .1" longer though. Also the reason you show about 2.5 grs more capacity with water.

Checking, My load shows a loading density of 108% in the 357 Max. The loading density with same charge in the 350 Legend is only showing 81%.

Actually also, The case capacity shows in Quickload at 33.60 grs of water with the 357 Max. it shows at 36.80 grs of water for the 350 Legend./

Thanks for the info. Would you mind putting this load into Quickload and tell me what you get?

350 Legend - 18" barrel, 1:16 twist rate.

Bullet: 147gr FMJ flat point
Diameter: .355
case: Starline
Primer - Remington 7 1/2 small rifle magnum.
Powder: Winchester 572 - 10 grains
COL: 2.000"

If you can, do the same load but with 11 grains of Hodgdon Longshot to compare to 572

Thanks

 

[dhagerty40]

Thanks for the info. Would you mind putting this load into Quickload and tell me what you get?

350 Legend - 18" barrel, 1:16 twist rate.

Bullet: 147gr FMJ flat point
Diameter: .355
case: Starline
Primer - Remington 7 1/2 small rifle magnum.
Powder: Winchester 572 - 10 grains
COL: 2.000"

If you can, do the same load but with 11 grains of Hodgdon Longshot to compare to 572

Thanks

Have to ask, who makes the bullet? I could not find winchester 572 but I am waiting on an update for quickload. I am about 2 years out and should have the update by monday..

 

[Timmis2]

Have to ask, who makes the bullet? I could not find winchester 572 but I am waiting on an update for quickload. I am about 2 years out and should have the update by monday..

I have 147gr flat point FMJ's by RMR (Rocky Mountain Reloading). QuickLoad won't likely have that brand in their list, but they aren't very different than other brand 147gr flat point FMJ's other than the fact that people have reported that they don't have jacket/core separation at velocities above pistol velocity

 

[dhagerty40]

I have 147gr flat point FMJ's by RMR (Rocky Mountain Reloading). QuickLoad won't likely have that brand in their list, but they aren't very different than other brand 147gr flat point FMJ's other than the fact that people have reported that they don't have jacket/core separation at velocities above pistol velocity

The only bullet I could find that closely match was the Hornady 147gr FMJ RN, so I used that. A bunch of the newer winchester powders are missing, but the update has a bunch of new powders and bullets, so might be included with that. This is with Hodgon Longshot..
it gives you info for if you try different powder charges, what will be predicted:

 

[tommeboy]

Your data shows titegroup not longshot

 

[Timmis2]

The only bullet I could find that closely match was the Hornady 147gr FMJ RN, so I used that. A bunch of the newer winchester powders are missing, but the update has a bunch of new powders and bullets, so might be included with that. This is with Hodgon Longshot..
it gives you info for if you try different powder charges, what will be predicted:

Thanks! I sent you a DM

 

[Timmis2]

When the 350l first came out we used 357max load data. So yes you can use it for the 350l. Might not work for your ar15 but it will for a bolt gun. Stay away from lilgun. It is way too temperamental for the 350l. What looks like a safe load will blow the primers out 2 hours from when you just shot them. And make sure to use a mag primer with any ball powder.

do you recommend a magnum primer with 350 Legend loads using reduced powder charges such as Titegroup with 30% case fill for subsonic loads? Or magnum primers for 350 Legend "normal" loads with powders like Enforcer, Lil gun, and IMR 4227?

 

[dhagerty40]

Your data shows titegroup not longshot

oops. guess i should have gotten more sleep!

 

[dhagerty40]

ok, here is with longshot. i also included the load data from Hodgon separately.

 

[tommeboy]

do you recommend a magnum primer with 350 Legend loads using reduced powder charges such as Titegroup with 30% case fill for subsonic loads? Or magnum primers for 350 Legend "normal" loads with powders like Enforcer, Lil gun, and IMR 4227?

Mag in anything with full power. Reduced loads regular sr are fine. Some of my cast bullet loads for the bolt were with sp primers just because. SP are good to around 38K. CCI sr are only good to 45K so be mindful of which primers you use for what. The mag primers are not only for the extra flame temp. The thicker cup works better if you have a bolt that will blank the primers. The 41 primers help with the unreliable ignition of this cartridge. It sucks that it falls in an area that not one powder is right for it. But with a bolt gun you can make things work that an AR15 will not.