.357 loads that are easy on a 19-3 and 66-1

[txtad]

Howdy!

I have a 19-3 and a 66-1 that I would like to shoot quite a bit. I know these guns aren't up to a steady diet of full power loads, especially if they have lighter bullets. I do like these guns and want to shoot them quite a bit with a load that is more than .38 +P but less than a full power .357 Magnum.

I thought this would be easy, just down-load to about 25K to 28K psi, but then I learned that the Treasury Load, 110 gr .38 Special +P+ at "only" 23,000 psi has been known to be hard on K frame guns. I know that the light bullets are much, if not all the problem with these guns, but I was still very surprised to learn that they're a problem even at that pressure level.

I am looking for suggestions as to what .357 Magnum -P loads to work up for these guns. I'm thinking there is no reason to shoot anything besides lead or plated 158gr bullets, but I'm not sure if I'm better to use starting loads of slow powders like W296/H110, something in between like 2400, or faster powers like 244 or Unique. Are starting loads good enough, or do these guns just need .38 Special level loads?

I'll be using .357 cases only. I have plenty of .38 Special revolvers if I want to shoot a .38 in a .38 case.

Thanks!

 

[OKFC05]

Well, lets start with W296/H110: don't experiment with it. It's best for a narrow range of hot loads in .357, and odd results have been reported with reduced loads.
Any of a baker's dozen of medium powders, including HP 38, are suitable for loading .38 +P and "mid-range .357" loads that are good for routine use in K frame .357 revolvers in good condition. One of my favorites is 7.5gr HP38 under 125grHP in a Model 65 for carry. I have shot a truckload of .38 +p 158gr in Model 66s for action pistol competition.

There are two separate issues with ammunition for old K frames
1. They are not made for a steady diet of max power .357, for which a 586/686 is better to avoid shooting loose.
2. The flat on the bottom of the forcing cone can crack from impact with max SPEED light bullets. Light bullets are not an issue with any .38 or reduced speed .357.

 

[Protocall_Design]

I prefer to stay away from ball powders for anything other than target loads. The ball powders at higher pressures tend to act as a sandblaster and erode the forcing cone with longitudinal grooves, similar to water erosion on a hillside.

The W296/H110 powder is ball, plus a bad idea to download as mentioned by OKFC05. I would try H4227 for that "more than target, less than magnum" use. I have had really good performance with that one over many years. Green Dot or Blue Dot are other ones that would fit well.

Polymer coated bullets have worked well in my guns, as well as cast and lubed and jacketed. Copper plated, not good.

 

[rockquarry]

A favorite .357 Magnum load I've used for many years is a mild one but quite accurate and is suitable for any revolver in sound condition. It's a milder load than many, but suitable for anything one would use a .357 Magnum revolver for:

Hensley & Gibbs #51 design, the original .357 Magnum bullet, 158 grain cast SWC, approximately wheelweight alloy or a little softer and sized to .358", 12 grain #2400 powder and a CCI-500 or CCI-550 primer, about 1100-1150 fps from a 6" Python.

14 grs. 296/H110 will do the same with good accuracy, but with horrendous muzzle flash and blast. I avoid this powder but some are captivated with the noise and flame.

Primers other than CCI may be fine and if you have them on hand try them. With the recommended charge of #2400, there is no reason to reduce the charge when switching primers as the load is not maximum.

The bullet...if you don't cast and don't have this bullet, try a variety of 158 grain cast SWCs. Stick with the one that is most accurate and doesn't lead the bore. There is no advantage to using a jacketed bullet over a cast bullet that fits. Read about cast bullet "fit" elsewhere.

This information is only useful if you intend to shoot 25 yard groups over a solid benchrest using good technique so that you can find the most accurate load for your gun. Don't waste your time shooting up close as you'll gain nothing in terms of useful information. Shoot lots of groups and your effort will pay off.

 

[rockquarry]

I second what Protocall design mentioned about 4227 powders, either one. Certainly worth trying. I'll stick with #2400, only because I've had far more experience with it.

Plated bullets...he's probably right on that one, too. I've only used them once, but that was enough to tell I needn't try them again. If best accuracy is unimportant, they are probably fine.

As for coated bullets, I've never tried them or had a reason to try them so far. Cast and conventionally lubed bullets have been fine, but you may find you like coated bullets as well or better for your situation.

 

[H Richard]

My recommendation is never load anything lighter than a 140 Grain bullet. There are plenty of loads available in these ranges and you don't get the top strap cutting and sandblast forcing cones. I would look for loads in the 38 Special Plus P range, with slower burning powders. Unique is an old standby, but best only if each load is loaded separately, not on an automated loading press. The flake powder doesn't flow through the drop tube accurately.

 

[Hair Trigger]

Howdy!

I have a 19-3 and a 66-1 that I would like to shoot quite a bit. I know these guns aren't up to a steady diet of full power loads, especially if they have lighter bullets. I do like these guns and want to shoot them quite a bit with a load that is more than .38 +P but less than a full power .357 Magnum.

I thought this would be easy, just down-load to about 25K to 28K psi, but then I learned that the Treasury Load, 110 gr .38 Special +P+ at "only" 23,000 psi has been known to be hard on K frame guns. I know that the light bullets are much, if not all the problem with these guns, but I was still very surprised to learn that they're a problem even at that pressure level.

I am looking for suggestions as to what .357 Magnum -P loads to work up for these guns. I'm thinking there is no reason to shoot anything besides lead or plated 158gr bullets, but I'm not sure if I'm better to use starting loads of slow powders like W296/H110, something in between like 2400, or faster powers like 244 or Unique. Are starting loads good enough, or do these guns just need .38 Special level loads?

I'll be using .357 cases only. I have plenty of .38 Special revolvers if I want to shoot a .38 in a .38 case.

Thanks!

I assume you have a good reloading manual? I use Hornady data almost exclusively for all my reloading, and I do very little experimentation using powders not mentioned for a particular caliber and bullet weight in the data charts. If you stay near the light end of the data charts for a particular powder you'll be fine. A hot .38 Spl+P load is generally about 900 fps, a light .357 Magnum load is around 1100fps, when using a 158 grain bullet. I don't have my manual handy at the moment, I have 4 .357M's I load for, including a M19-3 4" and a M66-1 2-1/2" and my loads for these two stay in the 1100 fps range (measured by whatever barrel length is used on the test gun). Hotter loads I reserve for the two 6" N frame .357M's I shoot. I stick with 158 grain JHP's on all my loads, it simplifies my bullet inventory and ordering in quantity usually gets a bit of a discount.

In the past, I've put many full power magnum loads through two other K frame .357M's I used to own (6" M19-2, 4" M66) and many of them were 125 grain JHP's. I never had any issues. Prevailing wisdom is to stay away from lightweight bullets, less than 140 grain, when using full power loads in a K frame magnum. Doing that, and loading on the light end of the powder range should extend the life of your K frames

 

[pantannojack]

I've been using 158g lead GC bullet in 357 mag cases, dropped from Lee mold. Sized .357 and now I got a .358 die. I was using some red lube required a heater or a aluminium bell with 60w light bulb aimed at the press.
Either with or without GC. It matters not with 6.5g-6.7g 4756. In my 586, I have had no leading even up to 13g 2400, or 14.5g 4227. Mag or std primer similar results. After experimenting with the 2400 and 4227, I have reverted back to 6.5g 4756, or 6g Unique for entertainment loads. I got poor accy with the hotter loads. on the phone Hodgdon cut me off at 10g HS-7 even though some older books book show much more. It's discontinued anyway. Tech said something about comparing copper crusher method vs electro piezo for seeing pressure. In my 19-2 I will stick with 6.5g 4756, 6g Unique std primer. Or shoot 38 spcl cases with 4.2g 231. I don't proof read much as anyone might see.

 

[dobegrant]

My fun .357 load is 5.0 hrs of Titegroup and a 158 gr swc

 

[Narragansett]

I do not reload much anymore, but when I did, I used nothing but 2400 powder and cast lead SWC or copper jacketed of the 158 gr. variety in magnum loads. I have experimented with lighter bullets, but pretty much settled on the caliber design weight bullet. I would be mindful of the light bullets in the K frame with the flatted barrel portion as seen at the forcing cone. My reason for using 2400 was that a double charge spills over the case mouth. Just an added safety feature for me.

If I were going to play with light bullet high speed loads, I would use an N frame M28. I agree with the previous statement about not feeding K frames a steady diet of max loads. They do not have the mechanical integrity of an N frame

 

[alwslate]

For mild economical .357 loads use faster powders with plain 158 gr cast SCWs. Four good loads chronographed from my 4" model 27-2.
5.6 grs Titegroup velocity = 1056 fps
5.3 grs of Bullseye velocity = 1012 fps
5.7 grs Bullseye velocity = 1057 fps
5.8 grs W231 velocity = 1060 fps.
Consistency is way better than loads with slow "magnum" powders like 296/H110 with less than half the powder. 14.0 grs of 296 chronographed at 1059 fps with a ridiculous 135 fps extreme spread. ESs of the loads with the three faster powders were less than 20 fps.
The loads listed were in Winchester .357 brass and used WSPM primers.

 

[rockquarry]

I do not reload much anymore, but when I did, I used nothing but 2400 powder and cast lead SWC or copper jacketed of the 158 gr. variety in magnum loads. I have experimented with lighter bullets, but pretty much settled on the caliber design weight bullet. I would be mindful of the light bullets in the K frame with the flatted barrel portion as seen at the forcing cone. My reason for using 2400 was that a double charge spills over the case mouth. Just an added safety feature for me.

If I were going to play with light bullet high speed loads, I would use an N frame M28. I agree with the previous statement about not feeding K frames a steady diet of max loads. They do not have the mechanical integrity of an N frame

Other than slightly reduced recoil, I can't imagine what advantage there would be in using bullets lighter than the weight for which this cartridge designed, 158 grains. Incredible accuracy of a lighter bullet might offset the use of a 158 grain bullet, but that's probably unlikely.

 

[cowboy4evr]

I have loaded for the K-frame 357 Smiths for eons . I have " always " used a 158 gr cast bullet -- or heavier . I have loaded them from " mild --wild " . My everday load for years was a 158 cast bullet using 7.0 grs of Unique . Due to a previous administration Unique became impossible to find . I switched to Winchester Super Field , think of it as a slow burning Unique . My everday load and the one used most often is 7.5 grs of WSF using a 158 gr cast bullet and a std small pistol primer . I don't have a chronograph but suspicion it runs about 1100 fps out a 4" barrel . That load is easy on the gun and easy on the shooter and WSF is easier to find than Unique . I have found , using H110 / W296 ( same ) that 16 grs just touches the base of the cast bullet giving superb accuracy and when I tipped the muzzle up to unload spent cases they literally fell out of the cylinder . I always use a magnum primer with H110 . That is not a max charge according to Hodgdon's but my favorite for sure in the 357 when I want more and yes I was shooting these in my model 19 4" barrel . I have no doubt I will wear out before the gun does using either of the above loads . Good luck , Regards Paul

 

[Retired W4]

Not a reloader but I have put countless 125 gr JHP factory 357 rounds through my 2 1/2" 66-1 since I bought it new in 1978. Quite a few 110 JHPs as well. No throat erosion or cracking of any kind. I did shim it for some end shake some time ago.

I always heard the lighter, high velocity bullets were bad for it but I'm not seeing it on mine. Function and accuracy are as good as it gets, and I have shot it a LOT in 45 years. Your experience my be different but I say run what you want in it.

 

[stansdds]

The 357 Magnum cartridge case is incredibly versatile. You can load cast or even swaged lead bullets with Bullseye and duplicate 38 Special. For such loads I usually add 0.2 grains to the 38 Special data as the larger Magnum case results in lower operating pressures. For K-frames, I'd stay away from the slow burning ball powders H-110 and W-296 as they are the ones that will erode the forcing cone the fastest. Unique works well in the Magnum case when you want velocity to exceed what you can get with 38 Special +P, but want to stay well below full power Magnum levels.

 

[Nevada Ed]

If I have to use a .357 Magnum case for high volume range time & loads
I opt. for the 158 gr lead bullets for 25 out to 100 yard work.

For out to 25 yards I use light loads that are under 1,000fps with the fast powders, to keep prices down.
Most medium burning powders will offer loads in the 1,120fps area for those
50 to 100 yard targets, if needed, in my 6" barrels.

A full loaded 158 gr lead bullet at 1250-1320fps, will reach 200 yards, but a scope sure helps out if you want to hit something.

Have fun.

 

[M29since14]

For mild economical .357 loads use faster powders with plain 158 gr cast SCWs. Four good loads chronographed from my 4" model 27-2.
5.6 grs Titegroup velocity = 1056 fps
5.3 grs of Bullseye velocity = 1012 fps
5.7 grs Bullseye velocity = 1057 fps
5.8 grs W231 velocity = 1060 fps.
Consistency is way better than loads with slow "magnum" powders like 296/H110 with less than half the powder. 14.0 grs of 296 chronographed at 1059 fps with a ridiculous 135 fps extreme spread. ESs of the loads with the three faster powders were less than 20 fps.
The loads listed were in Winchester .357 brass and used WSPM primers.

Good advice, I think! My approach is very similar, except I’ve never seen a benefit to magnum primers in the .357 loads I’ve tried with them. I use 160 gr. LSWCs or the Lee Cowboy design and something very close to the above listed charge of 231 for about 1000 FPS in my 4-inch Model 66. Seems like it should be pretty easy on the gun. When I shoot 100 yards or farther, I change to 13 grains of 2400. My .357s get way more of the 1000 FPS load than anything else - more than all the others combined.

 

[Brian Parrish]

Forcing Cone

I have understood two things about these guns.
#1 Small bullets. The 125 Federal hollow point became almost mythical for a period of time. It was singled out as the magic "manstopper" in the days of Marshall and Sanow (1992). However, that bullet is too short to seal the tube, the nose is not all the way in before the base clears the gap and allows hot gases to surround the nose in the forcing cone and enter the barrel in front of it. This is where the damaging pressure occurs. The 158 grain bullet is plenty long enough that this is not a problem. Many shooters report many years of no problem with thousands of these rounds.

#2 Leading. When going to practice with a revolver it is very common to shoot a lot of lead practice rounds and finish up with a few copper-jacketed defense rounds. But if the forcing cone is badly leaded the copper-jacketed bullet hits the now more narrow opening and causes the forcing cone to split. How much leading? you will ask and that I don't know. Some have suggested starting with the defense loads and then switching to lead rounds. Clean the pistol and inspect leading at the forcing cone. This should be routine maintenance anyway. I am sure this scenario is even more critical if shooting 125 grain rounds and even worse 110 grain rounds.

Please correct me anyone, I am not the expert.

 

[BC38]

There are as many answers as there are reloaders answering the question.

I tend to follow just a few "rules of thumb".
1) use bullets in the 148gr-160gr weight range - plated, powder-coated, or lubed hard cast, depending on your personal preference and what you have available
2) load on the low end (90% of max) of published data for the powder you're using

Make adjustments as necessary to get the best accuracy from YOUR gun(s).
YMMV.

 

[alwslate]

Good advice, I think! My approach is very similar, except I’ve never seen a benefit to magnum primers in the .357 loads I’ve tried with them. I use 160 gr. LSWCs or the Lee Cowboy design and something very close to the above listed charge of 231 for about 1000 FPS in my 4-inch Model 66. Seems like it should be pretty easy on the gun. When I shoot 100 yards or farther, I change to 13 grains of 2400. My .357s get way more of the 1000 FPS load than anything else - more than all the others combined.

I have made many comparison tests with std vs mag primers by chronographing velocities of various loads in the .357 with loads of around 1,000 fps to 1,400 fps. With loads around 1,000 fps velocity is increased by 5-10 fps and ES is always decreased with mag primers. Using heavier loads with 2400 velocity is increased by as much as 100 fps or more with mag primers and ES is greatly reduced. Example, 13.0 grs 2400, std primer, velocity = 1135 fps. !2.0 grs, a full grain less powder, WSPMP, velocity = 1225 fps with a greatly reduced ES. There just isn't any downside to using mag primers with all .357 loads that I can see. Same price, maybe more available and most loading manuals have always used mag primers in deference to the tall for diameter .357 case. People seem to think mag primers are dangerous in some way but original Hercules and Alliant .357 loads used the Federal 200 primer with all powders. It was listed by Federal as a SR and SPM primer both until recently. So to me the question isn't why use mag primers but why not?