357 mag revolvers
- Thread starter dhom
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ligonierbill
New member
I can share some approximate numbers from my 4" GP-100. I get best velocity (about 1,300) with 158 XTP using AA#9. Best std, too. H110 and 300-MP are just a little slower, not enough to bother, but the std is higher, especially with 300-MP. I am away from my data just now. I will note that 300-MP is the only powder to match commercial 125 loads. Don't load those much, but I wanted to see if I could. I don't know what another 2" of bbl length will do for you, but I agree that chasing a few more fps often turns out to be a waste of time.
For reasons known only to them, Hodgdon's site data was tested with a 10" barrel. Quite likely to give higher velocities.
However, lots of factory jacketed 158's will go higher than 1350 fps. Ballistics by the Inch shows Federal Hydra Shok 158 at 1458 FPS out of a 6" barrel.
However, lots of factory jacketed 158's will go higher than 1350 fps. Ballistics by the Inch shows Federal Hydra Shok 158 at 1458 FPS out of a 6" barrel.
Lyman manual shows a MAX load of 14.9 grains of AA#9 at 1357 using a barrel length of four inches. I think the extra 2 inches in your barrel will deliver the velocity you want. Of course if you were to use a rifle you could go with a heavier bullet and exceed the velocity you want. If you wanted to you could use a 140 bullet for your hunt as it is more than adequate and I have used with great success on some does. I shot one with my 686 and Colt python with 6" barrels one at about 70 yards and the other at 83 yards. Good luck on your quest.
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I reload all my ammo. I have exceeded the new SAAMI pressure limits with very good accuracy in the past [70's-80's] but, was in the standards for that time. I was just trying to keep with the newer pressures limits and get the same type of performance. I was hoping it can be done because the bullet performance on whitetails with the Hornady 158 HP worked extremely well for me at the velocity I have listed. The 357 mag's are a very popular round and I know a lot of experimenting is done with it. There are newer powders that I have never tried, but I want real world results. I was just hoping for some direction.
Accidents are accidents, and staying within current SAAMI pressure specs doesn't affect accidents happening. While staying within current SAAMI specs does avoid turning guns into scrap, it also avoids the full potential of your firearm.
And you didn't turn your gun into scrap??? Did the Pressure Police come and ticket you for loading ammo above current SAAMI specs???...The dragons did not eat you???....
Amazing!
(yes, that is deliberate sarcasm)I've read a lot of people on the web who give me the impression that they believe exceeding SAAMI pressure specs by even a tiny amount instantly brings doom and disaster. I don't believe this to be true.
All our guns survive proof firing without turning into grenades or even breaking or cracking. Proof loads are considerably higher pressure than SAAMI working load limits.
Its not a perfect analogy, but in some ways, SAAMI pressure limits are like the yellow speed limit signs on curves. They give you speed limit for taking that curve that everything on the road can do safely. Yellow signs are a warning, a suggested safe speed. Not the law. The suggested limit might be 25, and in certain vehicles, you definitely don't want to go faster than that on that curve. But with other vehicles, the actual safety boundary is different. The sign says 25, but my truck, with me driving, can stay on the road, and in my lane at 35. In my car, I can do it at 50. With a high end sports car, I might be able to do it at 80, or I might not, that's something I'd have to work up to, carefully. Kind of like max load development.
No, you shouldn't exceed SAAMI specs, if you are a manufacturer, because you are making a product that has to be safe for "everything on the road".
Handloaders are loading for themselves. Their individual results are only for themselves. They can push the envelope, and the only risk is to themselves. Some do go too far.
People pushing the "established limits" are why we have a .357 Magnum, .44 Magnum, & .454 Casull.
Stay within SAAMI pressure limits and be safe!!! it's a smart thing to do. (or so we're told)
OR don't, and all the risk on your head be it.
I grew up reloading in an era where the pressure numbers were just abstract data for the home reloader. What mattered to us wasn't the number of psi, cup, lup, attached to a certain load, what mattered was how the load performed in OUR gun. Pressure signs were our standard. Primer appearance, case head expansion, sticky extraction, etc. Those were what mattered, not the "book number" of psi.
Now, common wisdom today is that pressure signs are "unreliable" indicators of pressure. They are, and they aren't. They aren't reliable indicators of a specific pressure NUMBER, as too many factors are involved.
But they are reliable indicators that pressure has reached an undesirable level in your gun with those load components.
And that undesirable pressure level may be above or BELOW SAAMI specs, depending on the factors in your gun with your ammo components and loading. Below isn't common but it can happen.
Under the right conditions someone might run off that 25mph curve at 20. Someone else rides it like they were on rails at 50. It all depends on a host of factors unique to each individual vehicle and driver.
ALL handloading data is guidelines, not immutable natural laws. Every one of us is using a different gun, and different components, put together in different ways. Similar results are common, but any of us can be at either end of the bell curve, so that's why we say start low and work up CAREFULLY!
Also, don't get hung up on a specific velocity reading. Individual guns DO vary. Just because someone else's gun got XXXXfps with load A doesn't mean yours will. It might, but it also might be higher, or lower. I've seen 100fps difference between 3 different 6" .357s, shooting the same ammo. That much difference isn't common, but its not a freak occurrence, either.
In the future I will try some AA#9 and 300MP. Thanks for the replies. Somewhere back in the 70's I was shooting a local plate match with a Colt Trooper 6". It was steel plates 6" X 10" at 100 yds. offhand. A friend of mine was shooting on line next to me. I can't remember the reason but he ran short of ammo and asked me for some. In those days I wasn't well schooled on revolver strength and handed him some of my reloads. These consisted of 15 gr H2400, CCI mag primer, and a 160gr Keith semiwadcutter. His S&W model 19 did not hold up to the first shot. Luckily no injury to my friend. HAPPY HOLIDAYS TO ALL!!!!!!
buck460XVR
New member
....and like those yellow cautions signs folks need to realize, even tho they are just a suggestion, they are being suggested for a reason. There are yellow caution signs for pedestrian and deer crossing areas too. Ignoring any of them because one thinks they are not important is......well, asking for trouble. I found in Missouri, if the yellow caution sign says 45........you better slow down to 45, even with a motorcycle.
.357 was tamed down for multiple reasons. To extend the life of firearms, new and better pressure testing and the inventing of multiple larger and more powerful handgun calibers. There wasn;t always a .44 or .454. Folks used to push the envelope more because they has to because .357 was the biggest there was. That ain't so anymore.
armednfree
New member
You might want to up that to 180 grains. The 180 grain .357 XTP works well on deer. It stays together and punches through. Bullet weight is more important than velocity in a handgun, since energy levels are so low the hydrostatic shock effect is negligible. Better yet a WFN 180 grain cast gas check.
Chasing velocities is a path to firearm destruction; but . . .
. . . you mentioned that ^ so I'll spare the lecture. You have safety in mind.
Using Alliant 2400, I've wound up 158 XTP's to 1300 f/s (exactly, not rounding) through my 4" Smith 686. My chrono notes state difficult extraction and flattened primers; and to not go further. Standard Deviation soared to over 40. So I "set" the recipe with a less firearm punishing charge weight that delivered 1236 f/s with a 20.36 SD. That 1236 f/s though my 4" would likely translate to about 1300 f/s through your 6-incher. And your hefty Ruger could shoot these all day.
I used a lot of W296 in the past, and likely loaded them up to more velocity, but never chronographed them. Recoil, report, and muzzle flash were all tremendous. Back then, I was into that sort of thing. Nowdays, I feel loading such ammo to be unrefined and superfluous. Just my opinion. My current 2400 loading is plenty boomy enough.
Yeah, I tested Fed's Hydra Shok 158's through my Smith 686 8-3/8" bbl and got 1278 f/s. That was July '13. Maybe something has changed since then. And I also know they're using test bbl's; and I'm using a revolver.
Putting some wive's tales and questions to rest
The SAAMI pressure standard for 357 Magnum has never changed. The measuring system has. The original SAAMi specification calls for the average pressure of 10 rounds not to exceed 45,000 CUP. That standard remains in effect today and may be found in the SAAMI standard. However, when a load that gives that pressure is placed in a conformal transducer gun, the reading from the transducer is 35,000 psi. The difference in the two numbers is due to differences in how the measuring systems behave and are not a real difference in the sense that the loads don't produce any different velocity from the two types of test barrel. I got this in a phone conversation with former SAAMI Technical Director Ken Green about a dozen years ago. The difference in CUP and psi are always set by sharing reference ammunition loads in the two types of apparatus. Samples of the reference ammunition are sent to a number of participating SAAMI member facilities and tested, and the average copper crusher result and the average piezoelectric transducer result are used to provide a correction factor that sets the standard pressure.
So, why did load manual charge listings go down? Their authors started measuring pressure, probably out of liability concerns. Old manuals have loads worked up by pressure signs in a production firearm whose dimensions and reactions to pressure could be rather different from those your particular production gun would produce with the same load, using the same components. Today the maximum listed load pressures (at least) are measured during or after load development. The lower charges are often not measured but estimated, as with pressures listed by Speer for loads below maximum. Exceptions would be Hodgdon and Lyman who generally have pressure measurements for both starting and maximum loads. You do still find a few manual loads with a note stating they were developed by watching pressure signs in production guns because the manual authors didn't have a pressure gun for them or because there is no current SAAMI standard for them.
Most manual authors don't use the SAAMI pressure system the way ammunition manufacturers do. If you have looked through loads from Hodgdon or Lyman, you will have noticed the maximum loads given for different powders with the same bullet in the same cartridge have pressures that are different from one another and that are below the SAAMI pressure for the cartridge. To understand why, you first have to understand some basics of the SAAMI pressure measuring system. The following is applicable whether you are using the older copper crusher of the conformal piezoelectric transducer:
The commonly referred to SAAMI pressure limit is called the Maximum Average Pressure (MAP). It is the maximum value a ten-shot average peak pressure can have for freshly made loads (they have different limits for aged loads or additional samples taken of the fresh load). In a load whose ten-round sample produced the MAP, exactly, SAAMI expects to see the individual cartridge pressures scattered around that average, some above and some below MAP. They have a limit for the spread called the Maximum Extreme Variation (MEV). In the theoretical extreme, the highest individual cartridge peak pressure contributing to the peak pressure average could be as much as 18.3% over MAP, though its occurrence is extremely improbable.
However, the SAAMI allowance for variation above and below the average is based on the assumption its standard deviation will not exceed 4% of MAP for centerfire rifle or 5% of MAP for centerfire pistol and revolver ammunition. Additionally, SAAMI has standard velocity ranges for standard bullet weights fired in their standard test barrel lengths. So, a manufacturer will fire ten reference loads in his pressure and velocity test gun to get a correction scaling factor for its output. He will then work up a load to the SAAMI velocity range while watching that the pressure reading does not exceed the MAP. He will then fire ten rounds of the developed load to confirm the average peak pressure it produces does not exceed the MAP nor does it exceed the 4% or 5% SD (whichever is applicable to the cartridge he is making) and that the velocity remains in range after any adjustments to the load that may have proved necessary. The resulting data applies only to the lot of powder used for the load development.
Load manual authors know that different lots of powder will have variation in burn rate. If they used the SAAMI system the way an ammunition manufacturer does, someone who buys a faster lot of a powder than they developed the load with and who has a tight chamber or barrel, could well average over the SAAMI MAP, even though the manual author's test load did not. Additionally, handloaders often want to use powders they have on hand. As a result, a manual may list many powders for a particular combination of cartridge and bullet that are not the best choices for it, but that are convenient for the shooter. These sub-optimal choices often produce more than 4% or 5% standard deviation, which means wider variation so the load manual author may bring down the charge weight for that reason, too.
The way Hodgdon says they allow for powder burn rate and other causes of pressure variation and wide SD is they adjust the load so the highest pressure round out of the ten shot average is at the MAP, and not the average round, as an ammunition manufacturer would do it. This means all their loads, including the ones whose SD is within the appropriate SAAMI limit, are loaded to a MAP that is below the SAAMI MAP. That's what you see in the listings. A plus for the handloader, though, is that by looking for the powders with the highest listed peak pressures, you find the ones that produce the most consistent pressures and velocities. This is part of the reason you see manufactured loads with higher velocities than load manuals claim to produce.
As 44AMP said, pressure signs do not give you pressure numbers. They tell you how the particular components were affected by firing them in your gun. Case brass and primer cups are not calibrated to provide pressure measurements as the tarage tables do for copper crusher slugs. Components alloy and hardness vary by manufacturer. Moreover, Denton Bramwell demonstrated two different cases from the same original ammunition lot require a 2:1 difference in pressure to produce a certain amount of casehead expansion. So, even with pressure signs in your gun with your components, what happens to a case or primer is only certain to tell you what pressure that particular case is sensitive to, and you may have to fire a number of rounds and use an average to be sure of what you are seeing.
To T. O'Heir's question, SAAMI has several different length test barrels for some cartridges. One for revolvers, one for single-shot pistols, and, in the case of 44 Magnum, another for rifles. The .357 Magnum has a 4-inch revolver-type test barrel with 0.008" chamber/barrel gap to simulate revolver barrel/cylinder gap. Its length is measured from the gap forward, like a revolver barrel is measured. There is also a 10" barrel to simulate a single-shot silhouette pistol barrel and whose length is measured from the breech end like a rifle barrel is (see page 157 of the SAAMI standard, with a 10" barrel length as the bottom dimension, but 4" for red numbers for the revolver gap version). A same-length revolver barrel would be 8.402" long, so when you look for velocity difference you should only allow for 2.402" difference in length, and also that the 10" barrel has no barrel/cylinder gap bleeding pressure down. I can only guess that Hodgdon chose the 10" length because they happened to own the test barrel in that length and didn't have the revolver version.
The SAAMI pressure standard for 357 Magnum has never changed. The measuring system has. The original SAAMi specification calls for the average pressure of 10 rounds not to exceed 45,000 CUP. That standard remains in effect today and may be found in the SAAMI standard. However, when a load that gives that pressure is placed in a conformal transducer gun, the reading from the transducer is 35,000 psi. The difference in the two numbers is due to differences in how the measuring systems behave and are not a real difference in the sense that the loads don't produce any different velocity from the two types of test barrel. I got this in a phone conversation with former SAAMI Technical Director Ken Green about a dozen years ago. The difference in CUP and psi are always set by sharing reference ammunition loads in the two types of apparatus. Samples of the reference ammunition are sent to a number of participating SAAMI member facilities and tested, and the average copper crusher result and the average piezoelectric transducer result are used to provide a correction factor that sets the standard pressure.
So, why did load manual charge listings go down? Their authors started measuring pressure, probably out of liability concerns. Old manuals have loads worked up by pressure signs in a production firearm whose dimensions and reactions to pressure could be rather different from those your particular production gun would produce with the same load, using the same components. Today the maximum listed load pressures (at least) are measured during or after load development. The lower charges are often not measured but estimated, as with pressures listed by Speer for loads below maximum. Exceptions would be Hodgdon and Lyman who generally have pressure measurements for both starting and maximum loads. You do still find a few manual loads with a note stating they were developed by watching pressure signs in production guns because the manual authors didn't have a pressure gun for them or because there is no current SAAMI standard for them.
Most manual authors don't use the SAAMI pressure system the way ammunition manufacturers do. If you have looked through loads from Hodgdon or Lyman, you will have noticed the maximum loads given for different powders with the same bullet in the same cartridge have pressures that are different from one another and that are below the SAAMI pressure for the cartridge. To understand why, you first have to understand some basics of the SAAMI pressure measuring system. The following is applicable whether you are using the older copper crusher of the conformal piezoelectric transducer:
The commonly referred to SAAMI pressure limit is called the Maximum Average Pressure (MAP). It is the maximum value a ten-shot average peak pressure can have for freshly made loads (they have different limits for aged loads or additional samples taken of the fresh load). In a load whose ten-round sample produced the MAP, exactly, SAAMI expects to see the individual cartridge pressures scattered around that average, some above and some below MAP. They have a limit for the spread called the Maximum Extreme Variation (MEV). In the theoretical extreme, the highest individual cartridge peak pressure contributing to the peak pressure average could be as much as 18.3% over MAP, though its occurrence is extremely improbable.
However, the SAAMI allowance for variation above and below the average is based on the assumption its standard deviation will not exceed 4% of MAP for centerfire rifle or 5% of MAP for centerfire pistol and revolver ammunition. Additionally, SAAMI has standard velocity ranges for standard bullet weights fired in their standard test barrel lengths. So, a manufacturer will fire ten reference loads in his pressure and velocity test gun to get a correction scaling factor for its output. He will then work up a load to the SAAMI velocity range while watching that the pressure reading does not exceed the MAP. He will then fire ten rounds of the developed load to confirm the average peak pressure it produces does not exceed the MAP nor does it exceed the 4% or 5% SD (whichever is applicable to the cartridge he is making) and that the velocity remains in range after any adjustments to the load that may have proved necessary. The resulting data applies only to the lot of powder used for the load development.
Load manual authors know that different lots of powder will have variation in burn rate. If they used the SAAMI system the way an ammunition manufacturer does, someone who buys a faster lot of a powder than they developed the load with and who has a tight chamber or barrel, could well average over the SAAMI MAP, even though the manual author's test load did not. Additionally, handloaders often want to use powders they have on hand. As a result, a manual may list many powders for a particular combination of cartridge and bullet that are not the best choices for it, but that are convenient for the shooter. These sub-optimal choices often produce more than 4% or 5% standard deviation, which means wider variation so the load manual author may bring down the charge weight for that reason, too.
The way Hodgdon says they allow for powder burn rate and other causes of pressure variation and wide SD is they adjust the load so the highest pressure round out of the ten shot average is at the MAP, and not the average round, as an ammunition manufacturer would do it. This means all their loads, including the ones whose SD is within the appropriate SAAMI limit, are loaded to a MAP that is below the SAAMI MAP. That's what you see in the listings. A plus for the handloader, though, is that by looking for the powders with the highest listed peak pressures, you find the ones that produce the most consistent pressures and velocities. This is part of the reason you see manufactured loads with higher velocities than load manuals claim to produce.
As 44AMP said, pressure signs do not give you pressure numbers. They tell you how the particular components were affected by firing them in your gun. Case brass and primer cups are not calibrated to provide pressure measurements as the tarage tables do for copper crusher slugs. Components alloy and hardness vary by manufacturer. Moreover, Denton Bramwell demonstrated two different cases from the same original ammunition lot require a 2:1 difference in pressure to produce a certain amount of casehead expansion. So, even with pressure signs in your gun with your components, what happens to a case or primer is only certain to tell you what pressure that particular case is sensitive to, and you may have to fire a number of rounds and use an average to be sure of what you are seeing.
To T. O'Heir's question, SAAMI has several different length test barrels for some cartridges. One for revolvers, one for single-shot pistols, and, in the case of 44 Magnum, another for rifles. The .357 Magnum has a 4-inch revolver-type test barrel with 0.008" chamber/barrel gap to simulate revolver barrel/cylinder gap. Its length is measured from the gap forward, like a revolver barrel is measured. There is also a 10" barrel to simulate a single-shot silhouette pistol barrel and whose length is measured from the breech end like a rifle barrel is (see page 157 of the SAAMI standard, with a 10" barrel length as the bottom dimension, but 4" for red numbers for the revolver gap version). A same-length revolver barrel would be 8.402" long, so when you look for velocity difference you should only allow for 2.402" difference in length, and also that the 10" barrel has no barrel/cylinder gap bleeding pressure down. I can only guess that Hodgdon chose the 10" length because they happened to own the test barrel in that length and didn't have the revolver version.
MuzzleBlast
New member
My guess is attornaphobia.
I wouldn't even put that ammo in my gun.
In my head - right or wrong - I have a "mental ceiling" for velocities of various ammo weights-calibers. And with 357 Magnum, I consider 1250 f/s (4" bbl) as the ceiling for 158 grain ammo. Anything more than that will raise an eyebrow with me. Now I know variables abound. I'm sure gobs of really slow propellant (W296, 4227, 300-MP, N-110, etc.) will clear 1250, but it would be awfully boomy ammo. Nothing I would care to shoot.
For 125's I consider the ceiling to be about 1400 (Federal 130gn Hydra Shok's hit 1430 in my 4" 686; but nothing I've loaded has hit 1400). So that Buffalo Bore stuff just seems ludacris to me.