Revolver Pressure ratings

[Outpost75]

What bothers me more than anything is them trying to cheat in guns that don't meet standard to arm our front line guys with. No excuse for that contemptible behavior. Sad Sad Sad

Amen.

[missionary5155]

Well if we could role the clock back to 1978 and through 1984 we would find hundreds of shooters using S&W 357 mag and 44 ag and a few 41 mag realizing that after 500-1000 rounds of practice and match rounds their S&W revolvers were falling apart. Parts broke. Parts wore out fast.
Not writing that some DW & Ruger revolvers did not suffer issues... but most DW and Rugers had few if any issues and were the top accuracy winners week after week.
I still shoot our 1978 DW 357 Mag revolver with loads that would tear a 357 S&W apart. I still shoot our 1982 DW 41 mag with loads that I would never shoot in our two Model 57's. And our Rugers are still chugging right along.

[fatelk]

With the S&Ws, is it the wear and tear from magnum loads that tears them up, or just normal wear and tear from frequents firing?

For example, what kind of longevity could I expect from my model 66 with 85% magnum loads, or a Model 10-5 with 125gr/800fps loads? Would you expect them to last significantly longer with moderate loads?

[35remington]

Can’t speak for the 66 but with standard pressure 38 loads the 10-5 is long lived.

It has yet to be disproven that the milder the loads the longer a gun lasts.

[megasupermagnum]

With the S&Ws, is it the wear and tear from magnum loads that tears them up, or just normal wear and tear from frequents firing?

For example, what kind of longevity could I expect from my model 66 with 85% magnum loads, or a Model 10-5 with 125gr/800fps loads? Would you expect them to last significantly longer with moderate loads?

Again, I never worked as an engineer, and never did any longevity tests.

I think it may be worthwhile to look at how they are failing. Everyone knows about the forcing cone cracking. It has also been said that velocity is the killer, especially those hot 125 grain loads. A heavier bullet should theoretically reduce the damage. The other ways I've seen them wear out involve cylinder endshake, and timing problems, as well as forcing cone wear, but that is a lesser matter in my opinion. Outpost would be better to answer in this regard. I do not consider flame cutting a problem myself. I have never heard of a gun that the flame cutting cause some kind of a problem beyond cosmetic. The cutting only gets so deep and that's that. Now the endshake has been called frame stretching. I don't believe that based on experiencing it on my own gun. Since I did not measure my cylinder when new, I can't say for certain, but what I believe happens is either the star in the rear of the cylinder, or the front of the cylinder that sets against the yoke gets peened over time. When I bought my model 57-1, it had .006" of endshake. S&W's are not tolerant of endshake at all, mine wouldn't even open the cylinder unless pushed to the rear. The fix is easy, you add endshake shims inside the cylinder against the yoke to hold the cylinder to the rear. In my case I added .005" to leave .001" endshake for function. Fixing the endshake is easy, but over time this is also opening up your barrel to cylinder gap. Mine is currently at .009", which is nearing the limit of what most people consider acceptable, but no real problems because of it. The fix if the BC gap gets too large is to set the barrel back. This is means a trip to the factory or gunsmith. The other problem I have never experienced myself is timing. As has been said, the fix is a longer hand to turn the cylinder. I believe I've heard of the cylinder notches or bolt becoming worn, but it can't be too common. One problem with the N frame 44 magnum is that under recoil the bolt can release the cylinder, and allow it to rotate. It is not dangerous per-se, but extremely annoying. This is another reason why I say the N frame limit is really only 41 magnum. There is a stronger bolt spring, but it did not fully cure the problem for me. The N frame was designed for the 357 magnum, and works fantastically with that caliber.

The very best thing, if you like S&W's and want to shoot a large number of strong, old school 357 magnums is to get the model 27, although the L frame is supposed to have been designed to fix the K frame durability issues as well.

[Outpost75]

Problem is that the S&W yoke barrel is soft, usually will not even register on the Rockwell "C" scale, but typically 80-90 Rb in the best case, so once the gun develops measureable end-shake, the longitudinal cylinder movement hammers the gun to death. Yoke barrel can only stretched twice before typical gun develops cylinder gap over pass 0.008"/hold .009" at which point the barrel must be set back a thread and refitted. I have inspected new S&W in the box which came from the factory with cylinder gaps larger than would have been allowed to ship at Ruger in the 1980s. By the time a gun with as little as 0.002" end shake is shot a few hundred more rounds you will also need to have a max.-width hand and cylinder stop fitted. By the second factory rebuild once you shoot it loose again you have exhausted the available oversized parts and you have prodced a $600 paper weight.

N-frames don't have this problem.

If you want to shoot a continuous diet of full-charge .357s buy a Model 27 or 28.

[fatelk]

Thanks guys. Now that I think about it, I remember that I put an endshake bearing in my model 66 when I bought it used about 10 years ago. It's a '72 vintage gun. I haven't shot it a whole lot since I've had it, and it's still nice and tight. I doubt I've shot more than a couple hundred rounds of full magnum loads through it; it gets mostly .38s. I've shot the 586 a fair amount more (had it a lot longer) and it's still tight, no noticeable endshake.

I love threads like this, very informative. I appreciate you guys sharing your invaluable experience. Thank you!

[fatelk]

For curiosity, I just checked cylinder gap on several of my Smiths.
The 66 (with an endshake bushing) is at .008".
The 586 is coincidentally also at .008". I don't remember ever putting an endshake bearing in it, but I may have at some point.
My 629-1 is at .006". I've shot a lot of hot magnums through it, no idea how many, probably high hundreds.
I measured a 29-3 and a 29-8 that are both like new, shot very little, and they're both at .007".
My most-favorite old Model 29-2 that I've had for over 30 years, measures .010". I must have put a bearing in it at some point, don't remember. I have no idea how many rounds I've fired through it, gotta be over a thousand.

I'm getting to where I don't care for the hard kicking magnums so much anymore. Two or three cylinders full of .44 magnum and I'm rather done for the day, so they aren't likely to be terribly abused much in the near future, at least until my boys get a little older, and hit the macho-look-at-me stage. If we ever get into shooting a lot of those, I'll have to buy a Ruger, and learn to like it!

It's funny how boys of a certain age seem to enjoy pain. I took a couple nephews shooting a few years back. They went through about 60 rounds of heavy loaded 45-70 rounds in an H&R single shot, then were laughing and comparing bruised shoulders.

[35 Whelen]

Brian Pearce works with labs where chamber pressures are tested and guns are tested, I never have. So Brian Pearce is more qualified than me. Brian Pearce has been involved in the development of cylinders which resulted is greater strength, and I have never been involved in any such project.

If you read all of Brian Pearce's writings, it pretty apparent he's more than just a cowboy with a computer bunch of guns. I've seen him mention in his columns and articles Rockwell hardness of specific revolver cylinders, loads that were tested by H.P. White labs, etc. He has definitely picked up where Elmer Keith left off.

35W

[Wheelguns 1961]

I don’t trust his load data. He publishes stuff that is way over book max.

[Silver Jack Hammer]

Wheelguns 1961, Can you give an example of Brian Pearce recommending load data way over max? I’m comparing his published data to current loading manuals and manufacturers published load data and I’m not finding it.

[35remington]

Sometimes he is a little over but I have not seen way over when it is considered in relation to known firearm limits. For example Alliant stops at 6.0 grains in the 38 using Power Pistol with a 158 grain bullet at Plus P. Some of his data went to 6.3, a difference that could be ascribed to different cases and specific bullet used.

Some of his Plus P listings I would not shoot much of in an aluminum J frame even if it says Plus P on the barrel.

[megasupermagnum]

I don’t trust his load data. He publishes stuff that is way over book max.

Stop looking in the Hornady manual. I finally had to give mine away.

[Outpost75]

DEA and FBI would not let agents carry any Airweight revolver, even off duty. In DEA testing done at Quantico K-frame Model 12-3s could not survive one trip over their modified tactical revolver course firing 110-grain +P+ Q4070 loads without failing.

Attachment 261389Attachment 261390Attachment 261391

I have two Model 12s and love them, but do not carry +P in them. Only wadcutters or Speer 135-grain Gold Dot loaded to standard pressure with 4.0-4.1 grains of Bullseye.

Attachment 261392Attachment 261393

[Larry Gibson]

Is there a source somewhere to look up "max" pressures for revolvers?

I tend never to push pressure limits, just curious as the data seems to be hard to find.

Rugers and Contenders will take more than average, obviously

But S&W N frames, K frames, and other revolvers?

I have been studying and researching pressure testing for many years. Also in the last 14 years+ I have pressure tested thousands of rounds of both rifle, pistol and the numerous revolver cartridges. I am unaware of any such "source" for max pressures for revolvers, especially for particular individual make and model revolvers. The manufacturers usually will recommend whether or not to use higher than standard pressure loads in any particular model.

The last post of Outpost75's is a good example. If I recall correctly the M12 Airweight revolver was not even recommended for +P use let alone +P+ 38 SPL ammunition. That 110 gr load was pretty potent as I recall. Would love to pressure test some sometime but haven't seen any in years. Many seem to think all factory and max loads in manuals are at SAAMI MAP for any cartridge.....just isn't always so...… But unless one can pressure test the best advice with reloading cast or jacketed bullets is to adhere to the data in current manuals (where ever possible) and to work up the load as per the instructions in most manuals. The problem is, with most revolver cartridges, over pressure signs usually do not appear until a load is considerably over the recommended MAP for the cartridge.

So how are you, the reloader, supposed to know? You don't.....that's why you should stick to manual data and use a chronograph. It takes pressure to get velocity all other things being equal. If your reloads are appreciably faster than similar loads in manuals then pressure may be greater than you think.....or want for a particular revolver.

As an example; some 26 years back I obtained a Ruger Security Six with a 6" barrel and had on hand a quantity of Hornady 125 gr XTPs. A purview of manuals showed one using Blue Dot and givng very good velocity. I worked up to that load with out any signs of "excess" pressure. The WSP primers were not excessively flat and the cases pretty much fell out of the chambers with little effort from the ejector. Velocity was 1690 fps (Oehler m35P) and accuracy was excellent. I shot perhaps 400+ of those loads finding them deadly on jackrabbits, rock chucks and coyotes. Never any indication of pressure problems. I had about 35 rounds in a box of 50 of that load left when I began pressure testing so decided one day to pressure test that load. Wow....out of the 7.94" Contender Barrel they ran 1940 fps at 42,200 psi! Again accuracy was excellent and no sign of "excessive" pressure. However, while the 42,200 psi was ok in the Contender I thought it being a bit above the SAAMI MAP for 35,000 psi for the 357 Magnum was asking a bit to much of the Ruger Security Six. Was it too much pressure for the Ruger? I can't say as the Ruger appears no worse for it....but I don't shoot that load anymore. I also saw the max load with Blue Dot under 125 JHPs was several gr less in the next version of that manual. That later manual with a milder load (that max load is at the SAAMI MAP) came out after they began using piezo-transducers to measure psi.

[Outpost75]

Larry,

The 110-grain +P+ load is still available in the Winchester Law Enforcement catalog:

Winchester 38 Special +P+ (110) JHP
Symbol: RA38110HP+ – Winchester Ranger Jacketed Hollow Point
Shellcase: 38 Special +P+ nickel plated brass shellcase
Bullet: 110 grain (7.1 gram) Jacketed Hollow Point, Brass jacket, lead core
Diameter 0.357 inch (9.07 mm)
Powder: Clean burning, low flash
Primer: Winchester non-corrosive primer – boxer type
Accuracy: Product Mean of 2.5 inch (6.4 cm) Extreme Spread, 5 shot targets at 50 yards (45.7 m) from a 7.71 inch (19.6 cm) SAAMI test barrel
Velocity: 990 ft/sec (302 m/s) nominal at 15 ft (4.6 m) Fired in a S&W Model 15 revolver with 2 inch (5.1 cm) barrel
Energy: 239 ft-lb (324 joules)
Pressure: 23,500 psi max. average (1,621 bars)
Waterproofing: Lacquer applied to primer annulus and Black Lucas applied to mouth of case

[megasupermagnum]

I have been studying and researching pressure testing for many years. Also in the last 14 years+ I have pressure tested thousands of rounds of both rifle, pistol and the numerous revolver cartridges. I am unaware of any such "source" for max pressures for revolvers, especially for particular individual make and model revolvers. The manufacturers usually will recommend whether or not to use higher than standard pressure loads in any particular model.

The last post of Outpost75's is a good example. If I recall correctly the M12 Airweight revolver was not even recommended for +P use let alone +P+ 38 SPL ammunition. That 110 gr load was pretty potent as I recall. Would love to pressure test some sometime but haven't seen any in years. Many seem to think all factory and max loads in manuals are at SAAMI MAP for any cartridge.....just isn't always so...… But unless one can pressure test the best advice with reloading cast or jacketed bullets is to adhere to the data in current manuals (where ever possible) and to work up the load as per the instructions in most manuals. The problem is, with most revolver cartridges, over pressure signs usually do not appear until a load is considerably over the recommended MAP for the cartridge.

So how are you, the reloader, supposed to know? You don't.....that's why you should stick to manual data and use a chronograph. It takes pressure to get velocity all other things being equal. If your reloads are appreciably faster than similar loads in manuals then pressure may be greater than you think.....or want for a particular revolver.

As an example; some 26 years back I obtained a Ruger Security Six with a 6" barrel and had on hand a quantity of Hornady 125 gr XTPs. A purview of manuals showed one using Blue Dot and givng very good velocity. I worked up to that load with out any signs of "excess" pressure. The WSP primers were not excessively flat and the cases pretty much fell out of the chambers with little effort from the ejector. Velocity was 1690 fps (Oehler m35P) and accuracy was excellent. I shot perhaps 400+ of those loads finding them deadly on jackrabbits, rock chucks and coyotes. Never any indication of pressure problems. I had about 35 rounds in a box of 50 of that load left when I began pressure testing so decided one day to pressure test that load. Wow....out of the 7.94" Contender Barrel they ran 1940 fps at 42,200 psi! Again accuracy was excellent and no sign of "excessive" pressure. However, while the 42,200 psi was ok in the Contender I thought it being a bit above the SAAMI MAP for 35,000 psi for the 357 Magnum was asking a bit to much of the Ruger Security Six. Was it too much pressure for the Ruger? I can't say as the Ruger appears no worse for it....but I don't shoot that load anymore. I also saw the max load with Blue Dot under 125 JHPs was several gr less in the next version of that manual. That later manual with a milder load (that max load is at the SAAMI MAP) came out after they began using piezo-transducers to measure psi.

That is a good example of the discrepancy. You would know better than me, but I'm willing to bet many of those older loads ran in the 40,000 to 45,000 psi range at max loads. These are the loads I like (not the 125 grain specifically), and accuracy can be phenomenal. There is no doubt there is more wear an tear on the gun, but I've seen no evidence that they are unsafe in the guns of the time. That's the price of a hotrod.

[Wheelguns 1961]

In an article for the 41magnum, he states that his go to load is 19.0gns of 2400 with a 220gn bullet. My lyman cast bullet handbook gives 16.2gns of 2400 with the same.

This is in response to silver jack hammer. I must have forgotten to hit the reply with quote button. This is brian pearce load data.

[downzero]

If 990 fps out of a 2" barrel is hot with a 110 grain bullet, you all would hate to see the chrono results from me firing 158 grain SWCs over the chrono last weekend. If I recall correctly, a book load of +P CFE Pistol put them 880 FPS. How is that +P+? Not that there is a standard for such a thing anyway.

[Outpost75]

Winchester spec. for 158-grain lead +P "FBI Load"

Winchester 38 Special +P (158) Semi-WC HP

Symbol: X38SPD – Winchester Super-X Handgun
Shellcase: 38 Special +P nickel plated brass shellcase with cap lacquer
Bullet: 158 grain Semi Wad Cutter HP
Powder Type: Clean burning
Primer: Winchester non-corrosive primer, boxer type
Accuracy: Product Mean of 4.0 inches Extreme Spread 5 shot targets at 50 yards from a SAAMI test barrel
Velocity: 1050 ft/sec nominal at 15 ft fired in a 7.71 inch SAAMI (solid) test barrel
(NOT revolver)
Energy: 386 ft-lb nominal at 15ft fired in a 7.71 inch standard SAAMI (solid) test barrel
Pressure: 20,000 psi maximum average
Waterproofing: Lacquer applied to primer annulus

Typical revolver velocities, as fired in new revolvers gaged at Mean Assembly Tolerance:

___________________________S&W Mod.10, 2”__S&W Mod.10 4”__S&W Mod.28 6”

-------------------------------------- 0.005”cyl.gap____0.005”cyl.gap___0.005”cyl.gap

Winchester X38SPD 158-gr. +P___831 fps, 10 Sd___909 fps, 16 Sd__952 fps, 11 Sd