What is "moderate" 357 ammo?

[farandfine]

Hello Everybody, I've read quite often that it's best to avoid hot 357 magnum ammo in K frame revolvers. And, in terms of the model 19s forcing cones, it's best to shoot moderate 357...if, you're going to shoot 357 magnum ammo at all. But few people seem to specify just what "moderate" means in terms of this round? Are 158 grain 357 rounds that go 1150 fps moderate? Are those that go 1200 fps still moderate? How about 1250?

Hopefully my curiosity and confusion are understandable. And if any of you can spare the time and effort to help me out here, I'd really appreciate it.

Cheers,
John

 

[EarlB]

The main issue with K frames are the 125gr loads, I wouldn't shoot those. If you use regular factory 158 grain loads you should be fine. Personally I wouldn't use any of the hot loads from Underwood, Buffallo Bore, Corbon, etc...

 

[mod29]

If you don't reload, use factory .38 Specials for target shooting. Any of those factory loads will be fine in your gun.
For the occasions that you want to shoot magnum loads, use factory 158-gr ammo. It's supposed to be easier on the forcing cone than the 125-gr.

If you're a reloader, I would suggest light magnum loads (low to mid-range) using magnum brass and 158-gr bullets for general shooting.

 

[muddocktor]

I'll also say to stay away from any 357 Mag rounds lighter than a 140 grain bullet with your model 19 too. As for more moderately loaded 357 factory ammo, I've found that the PMC Bronze ammo with 158 JSP grain bullets to be on the more moderate side. The Fiocchi 158 grain stuff is definitely loaded hotter than the PMC Bronze. And if you reload, you can tailor your ammo to whatever you want, even loading down to 38 Special levels.

 

[stansdds]

The Model 19 was designed when most shooting was with 38 Special ammo and the use of magnum ammo was just for familiarization and actual duty or hunting use. Also, 38 Special and 357 Magnum ammo of that time period did not generally feature bullets lighter than 140 grains. 110 and 125 grain 357 Magnum ammo was introduced in the 1970's and although it proved to be effective against two-legged predators, it also proved to be hard on the forcing cone of the Model 19 and 66, specifically, the portion of the cone that was milled away for crane clearance.

I have shot 110 and 125 grain magnum ammo in my 19-3 and it did not take long for me to see erosion at the edge of the forcing cone. These days, I do not put those lightweight magnum loads in my 19-3. It is far more comfortable shooting cast lead 148 and 158 grain loads that are in the 38 Special to 38 Special +P velocity range. If I want to shoot magnum ammo through it, it would be 135 grain reduced velocity magnum loads or 158 grain magnum loads and I would keep that to a minimum.

 

[slickracer]

158 cast bullet powered by 6.0 to 6.5 grains of Unique is a nice load.

 

[OFT II]

If you handload the old 38/44 load with a 158 grain lead slug over 2400 powder works great. It's my favorite K frame load. Just be sure to keep it away from any 38s except for the 38/44.

 

[oddshooter]

Hey OP,

I liked the way you asked the two questions.
It showed me you already knew the answer.
You asked in terms of velocity, for a moderate loaded 19, using 158gr.

I handload more of the 158gr than any other. Nothing below 148gr.
I shoot my many 357 mags from 750fps up to about 1450fps.
Math tells me that 1100fps is in the middle or moderate. That's right where you suggested and my favorite.
That isn't a light load and it isn't a hot load. Leading should not occur and the recoil is there, but not punishing.

I love variety so I handload for the entire range available.

On that weak 19 issue, I don't think I will ever get to the 20,000 rounds of hot ammo that might make that real. My reading tells me that it's the extra POWDER that is required for light for caliber bullets that causes the erosion, not the bullet. Don't shoot light bullets and you can still keep them hot.

Prescut

 

[Mistered]

I loaded up some .357 with 8 grains of Unique and two lots of 50 each with 125 gr. plated FP and 50 of 125 gr of 'old' Hornady JHP bullets. Data shows 9.6 grains of Unique with the 125 grain bullet at 1343 FPS but I have backed that off to 8 grains as 9.6 seem seems a bit 'stout'. 8 grains nearly fills the case and i am thinking these should be OK for 'moderate' shooting with my M-66 but primarily I am looking for a mid-range .357 load for my Henry BBB for general shooting and maybe some varmint hunting.

 

[Vulcan Bob]

I feed my K frame magnums 158gr LSWC at 1,050 fps. Yeah, I'm being a bit cautious here but they don't make em (old style) any more. For full house .357 Mag's I just go to my L and N frame revolvers.

 

[Texas Star]

Remington's brass jacketed 125 grain load at about 1250 FPS, is deemed "medium", as is the 135 grain Speer Short Barrel round.

 

[Benchrest1]

The Slickracer load works for me.

 

[BLUEDOT37]

But few people seem to specify just what "moderate" means in terms of this round?

Brian Pearce had a (4) page article in Handloader #248 (Aug-2007) about using milder loads in M19/M66s to avoid the premature loosening from a steady diet of magnum loads.

In short, he suggested limiting handloads to <30K psi, & preferrably in the mid 20K range.

.

 

[steelslaver]

On the forcing cone erosion issue.
If a load will erode the throat of a model 19 it will do the same thing with a L or N frame 357. The round fires under the same pressures in any chamber, the hot gasses are the same coming out of the brass and cylinder throat and make the same jump across the B/C gap and into the throat. All the blued models use same steel in barrel. So same effect on forcing cone itself. A model 19 does have less steel in this area and will fail from cone erosion thinning way before the rest. But, forcing cone erosion is good for none of them. A 19 that is eroded may crack before the L or N, but prior to cracking could have barrel removed, shoulder cut back enough for a turn or 2 and the cone recut just like and L or N with excess erosion, but who wants to do that or pay to have it done?

Stay away from loads that cause throat erosion be it in K, L or N frame.

 

[Peak53]

Since you specifically asked about a "moderate" load for 158 g. bullets ... I use 1200-1250 fps as the top end for lead in that category. If you start getting into 1300-1450 fps, that is more like "screamer!" That said, I shoot a lot in the 900-1000 fps range just for fun. I am less experienced with handloading jacketed 158's, so won't comment on that.

 

[iPac]

On the forcing cone erosion issue.
If a load will erode the throat of a model 19 it will do the same thing with a L or N frame 357. The round fires under the same pressures in any chamber, the hot gasses are the same coming out of the brass and cylinder throat and make the same jump across the B/C gap and into the throat. All the blued models use same steel in barrel. So same effect on forcing cone itself. A model 19 does have less steel in this area and will fail from cone erosion thinning way before the rest. But, forcing cone erosion is good for none of them. A 19 that is eroded may crack before the L or N, but prior to cracking could have barrel removed, shoulder cut back enough for a turn or 2 and the cone recut just like and L or N with excess erosion, but who wants to do that or pay to have it done?

Stay away from loads that cause throat erosion be it in K, L or N frame.

Good point.

It's helpful to know the real cause of forcing cone erosion, and that isn't the size/weight of the bullet.

125gr. loads don't erode/crack the forcing cones because it's using a 125gr. bullet, it has to do with the powder/heat. All forcing cone erosion is due to heat and pressure, but mainly heat.

To make a forcing cone last as long as possible, NEVER constantly fire rounds allowing heat to build up and carburize the metal cone. With my guns, I practice at a slow pace making sure no heat can build up.

This is why the lighter bullets cause erosion more rapidly. The lighter bullet exits quicker before all powder is burned which then hits the forcing cone. Shoot many rounds without a cool down and you carburize your cone. Eventually it will crack, especially with the K frame bottom cut-out. Hot-rodded loads just increase this.

I'm sure there's more to it, but that's the main gist of it.

 

[Mistered]

Someone correct me if I am wrong but wasn't a large part of the cracking K frames in the era of of the Super Vel ammo being used in them? I believe I read somewhere once this stuff was insanely hot - like 1600 + FPS with the 110 grain bullets.

 

[steelslaver]

While slowing down the rate of fire will slow down the erosion it will not stop it or evenslow it down that much, unless your comparing i to firing a whole bunch of rounds one right after the other until the barrel is hot enough to actually burn your hand. Although say 350 f is hot to you to steel that's absolutely nothing. The blasting of hot burning powder occurs very rapidly. Little of the heat from this is actually transferred to the forcing cone and heat built up is slow. But, all of the sandblast effect is every round no matter how slow the rate of fire.
22-250s, 220 swifts and under bore cases are some of the worst guns for this. You fire light super fast bullets using slower powders and itwon't take long to get the rifling just ahead of the throat frosted looking. Its not the bullet or the velocity or even the rate of fire. If it was velocity the muzzle area would go first as thats where the bullet is going the fastest.

Slowing down the rate of fire does help save a barrel but it won't slow down the blast effect of hot buring powder striking the bore, forcing cone or whatever. Try making a cylinder out of art board and firing your revolver in it repeatedly. Rapid fire slow fire I bet it will eat away that art board at the same rate and the art board will be a lot warmer after6 rapid shots compared to say 6 in 10 minutes.

Face it to get max velocity from light bullets it takes a bunch of powder on the slow end of a cartridges usable powder range. More burning powder striking the base of the bullet, the rifling and forcing cone is going to take a toll, every time no mater how fast the rate of fire.

 

[farandfine]

Thank you!

I've been away for a bit and just returned to see the later comments on this thread. Thank you to all who contributed their expertise. It's helped me better understand what all is involved.

Cheers,
John

 

[Nevada Ed]

I rate the S&W K frame as a HEAVY 38 frame and a light 357 Magnum frame
due to how it was made.

When I was young and wet behind the ears in reloading for revolvers
I thought "Hot Loads" were fun to shoot and nothing better than
a light 110 or 125gr bullet to get those sizzling fps!!


Sure I loaded a few boxes of the big 158gr. bullets but they were
for hunting or Metal Pigs.

I did know that they took a LOT MORE powder in a single load and
that there was a heavy dose of flame and noise with these super loads
but hay, it was fun, right?

Not to mention that the lighter 110 and 125gr JSP/JHP bullets left
the case and traveled, unsupported after the cylinder, to the forcing cone.
Unlike the larger 158gr bullets that were at or very close to the
barrel when it cleared the case, with a slower speed, less powder
and all in all, a better thing for shooter and revolver.

It only took me three to four years of those hot 110 & 125gr bullets
for me to finally "KILL" my lovely M19 6".

I learned that a 140gr XTP is a lot better for a K frame, for a practice session, than the full blown lighter bullets.

Good shooting.