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'd say, unless expressly stated otherwise, follow SAAMI pressure guidelines.
All aspects of manufacture cost money, and all firearms are products made to be sold for a profit. No manufacturer is going to put significantly more into the materials (steels and other metals) and processing (preparing the materials and general workmanship) than they think they can recoup. And they're competing in a world marketplace.
They are going to make a profit or go out of business; and we've seen plenty of firearms manufacturers either plain go under or end up outsourcing to someplace other than the US of A (including some longtime legendary American companies who no longer make anything here, not mentioning any names). So we can't make the assumption there is a huge safety margin built into the guns we buy, because of the economics of the situation.
I'm sure some of the folks here will pile on with exceptions and yea buts but that's my $0.02 worth, FWIW.
Google SAAMI and look up your cartridge.
Yes, SAMMI specs will be the safe maximum for ANY gun in that caliber.
Brian Pearce in Handloader magazine will run articles that are worth reading. He has written articles on loads for example .44 Redhawk, single action revolvers with different cylinder wall thickness, etc. I’m sure researching the history of his articles would be a good source.
Brian Pearce stated in one of his articles that he had a new .44 Special bored out to .44 magnum and he had been shooting it without any signs of stress. He also said he has worked with labs that pressure test but he can’t publish the data.
The problem there is that Brian Pearce is barely more qualified than you or I to say X gun can handle X pressure. We can extrapolate that similar cartridges in the same gun should be able to handle the same pressure, but that is it.Originally Posted by Silver Jack Hammer
The OP asked specifically about the old Ruger vs S&W debate. There are two parts to that, the actual safety factor, as well as durability. As far as safety, as I said, the SAMMI pressure spec is safe in any gun ever made in that caliber. Now I'm willing to admit that a Ruger Redhawk 44 magnum is likely going to handle more pressure than say, as S&W model 69 44 magnum L frame. But I never worked as an engineer for any firearm company. So how much stronger is the Redhawk, nobody can really know for sure. The redhawk and super redhawk share the same cylinders. Since the super redhawk is offered in 454 casull does that mean the 44 magnum version can handle 60,000 psi? Not exactly. I'm fairly sure the material the cylinders are made of in the higher pressure round is different than the 44 magnum.
Now another wrench in those gears is that while SAMMI is the american standard, much of the world follows the european standard of CIP. Taking that same 44 magnum, the SAMMI standards are 36,000 PSI or 40,000 CUP. The CIP standard is 41,000 PSI. An even bigger discrepancy exists in 357 magnum. In that case, the SAMMI standard is 35,000 PSI or 44,000 CUP, while the CIP standard is 43,500 PSI.
Then we come to load data. Most new load data is to the SAMMI specifications in PSI using the new pressure testing methods. While it has been considered no correlation from CUP to PSI, there is some as proven in the following link. https://www.shootingsoftware.com/ftp/psicuparticle2.pdf
You will find that for the most part, old load data is pretty dang close to the new data. The old timers knew what they were doing. Sometimes, especially in said 44 and 357 magnums, they could be much stronger in the old data. There are multiple factors for this, including new testing methods, as well as weaker guns.
So with safety in mind, is the old data dangerous? I do not consider it dangerous, not in the guns of the time or current guns just as beefy. I would not shoot those loads in a J frame or the model 69. The other factor is durability. This we can say with more ease, as there is nothing at stake except wear and tear. I have said it before that the S&W model 29 is barely adequate for the 44 magnum. By that I mean it will not handle thousands or tens of thousands of rounds of full snort ammo. That can mean different things to different people. But they are perfectly safe. While the Ruger Redhawk can take those same loads and live a long life. There will always be a few examples on both sides to say the contrary, but the Redhawk is more durable than the model 29, as shown by those who fired tens of thousands of rounds a year at steel silhouettes. You mention the K frame in 357 magnum. That gun is quite safe, but can suffer durability problems. That was its intended purpose. It was meant to take the strong rounds, but not to be campaigned on a target shooting binge. A more reasonable diet of a few hundred rounds a year of even extremely strong ammo should cause no harm to the gun for a long, long time. In the case of the J frame, there is no way that it is as strong or durable as the larger guns like the N frame or GP100.
Does that muddy the waters enough?
Last edited by megasupermagnum; 04-30-2020 at 01:17 PM.
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.
My involvement is limited to reloading for guns manufactured to dimensions over 100 years old with modern steels. You may say you and I don’t know anything about metallurgy, and you be right but I have been told modern steels are stronger than older steels and I believe it. When we discuss older data, I reload for cartridges developed during the black powder era.
Some load data of old is considerably in excess of SAAMI specs today as said spec did not exist at the time and the pressure measuring equipment they used was somewhat less than accurate.
Older guns are also made of softer steels. In many cases, such as 38 Special, there is no valid reason to consider anything other than recently published data, and some risk in using old data especially when paired with older guns. The durability issue arises here, and not just for aluminum J frames.
It is common for S&W K frame barrels to fail through cracking at the 6 o'clock position over the barrel flat, where the section is thinner due to the clearance cut for the cylinder gas ring.
In 1984 the USBP received 707 S&W revolvers that their weapons specialist at FLETC had major problems with and the INS Director of Training was informed that the revolvers could not be issued due to multiple major category defects.
The initial contract was a canned S&W document of simple description written specifically to disqualify the other two revolver manufacturers. There was no performance requirement and no requirement for acceptance testing. The INS Director requested assistance from DOJ and the US Army Materiel Command to provide a performance spec. which was then provided by the Army. Five "hard fitters" arrived from S&W, along with Dennis Lee S&W Fed Sales Rep and L Kwisnak who was in charge of QA for S&W. They worked on the pile of guns for a week and 34 guns had to be returned to the factory as beyond repair NIB.
The S&W reps requested an "exit interview" with USBP personnel and the Government's Contracting Representative. Attending were a BP Colonel, Major, Captain and their weapons specialist and the Engineering Test Director detailed to FLETC from the Aberdeen Proving Ground.
S&W made their presentation. The BP gunsmith informed them the next contract would require a performance spec firing 10,000 rounds of 357 Magnum ammunition with no failures. Kwisnak of S&W spoke up and said no revolver now produced in the industry could meet such.
The Director then asked "how long a S&W would hold up?" Kwisnak of S&W clearly did not want to answer the question and finally said "3000 rounds." The BP Command Officers were all visibly shaken. The Director then asked what the failure mode was on the S&Ws. Kwisnak clearly did not want to answer and finally admitted, "the barrels crack". The BP Command Officers were NOT amused.
Finally Dennis Lee of S&W asked if there were further questions. The Government's contracting representative from Aberdeen Proving Ground asked Kwisnak what he meant by "crack?" and asked specifically "was there loss of dispersion, loss of velocity or catastrophic failure," (the latter being what had been observed in the failed guns tested at Aberdeen Proving Ground).
Dennis Lee immediately said without answering the question they were late for their flight and the S&W folks all left quickly. The INS Director reviewed the "Confirmation of Information Understood" memo prepared by attendees and addressed to Kwisnak. The BP Command Officers had all come directly to him and reported what they heard and that they were NOT happy. The memo to S&W was in the PO before the S&W folks got to their flight in Jacksonville, being sent registered return receipt. The receipt came back and no response was ever received from Kwisnak.
The next USBP contract contained a 10,000 round endurance requirement based on DR1187, the Federal Revolver Specification for .38 Special written by the US Army during the Vietnam war period for revolvers intended for combat aircrews, security police and CID investigators, with changes to remove any references to Defense Contract Administration requirements and reflected that the ammo would be commercial 357 Magnum. Otherwise, it had the same mechanical/performance requirements as the existing Army .38 Special revolver spec. in use since the 1960s.
Low initial bid was S&W and testing commenced. At the end of the first evening both test samples submitted were "out of time" at 500 rounds. The BP weapons specialist installed a "oversize hand" and the next evening they shot another 500 rounds and the guns were out of time again, rebuilt again and they both took .099" hands to bring them into time. The third night another 500 rounds were fired and they were out of time again and the BP notified S&W they had failed.
Ruger's Government Sale Rep Steve Vogel called me at Newport, NH and informed me that the USBP had referred him to contact specific named engineers at Ruger. As QA Manager I consulted the named engineers, referred the answers to their questions and Steve called back the following morning providing the address of where test weapons were to be sent and that is how Ruger got invited to the competition.
The USBP had purchased 40,000 rounds of .357 Mag 158 Gr. JHP and all ammo was from one ammo lot per the spec. Ruger had sent two Service Sixes with 4" barrels and both guns met the spec and the Border Patrol bought a large number of Rugers.
Steve Vogel requested copies of the FLETC test report both under FOIA and directly from USBP and later had a large number of copies run which Ruger sent out all over the world. Aberdeen Proving Ground soon afterward distributed copies to the Defense Criminal Investigative Service, Naval Sea Systems Command, Department of State Security and Rock Island Arsenal.
A follow-on test was conducted for a plain-clothes, round-butt model with 3" barrel. INS investigators bought 500. The Brits also bought a large number as well.
About the time I left the company the Firearms Branch at FLETC had obtained one of the then-new GP100s and last I heard it had 15,000 rounds on it and was doing fine.
I heard later that S&W submitted its L frame, which passed and Ruger did as well so both were qualified and CBP bought low bid. Subsequently the L frame was found to exhibit a "design flaw" which necessitated a nationwide recall on the L frame to replace the striker nose with a smaller one and install a new recoil shield to correspond with smaller diameter striker nose. But in 20,000 rounds we shot up at Ruger testing our competitor's product we did not experience the reverse primer flow problem that led to the recall.
William C. (Bill) Davis of Tioga Engineering was contracted by S&W to determine what caused the reverse primer flow and determined what it was and thus the recall. As Bill explained to me, the hammer pivot pin was mis-located and even when the revolver met indent requirements it would not hold the pressure of full-charge .357 long enough for the pressures to relax. Thus the primer material flowed into the striker opening and locked the guns up where they had to be beat open. About that time there was also an issue with the proofing and the government's QAR was sent to S&W to witness the repeat proof series after some guns were examined at Picatinny Arsenal and confirmed by the BATF laboratory by electron microprobe analysis of the powder residues, that the guns were not proof fired with six proof cartridges, one per each charge hole per the spec., but only one proof load and five regular service rounds.
In reproofing at S&W 1200 proof loads were fired in 200 guns and had 34 failures to fire. Per MILSPEC only one misfire per million is allowed. The misfired rounds were sent to Picatinny Arsenal and their analysis was the failure to fire resulted from excessive off center striker indents. The report obtained through FOIA indicated that was determined that firing pin off center hits in excess of .020" could lead to misfires. It is not uncommon to see off center striker indents in S&Ws weapons upwards of .030" offset.
In the time I was QA Manager for the Newport facility I never saw a Ruger off that much.
Last edited by Outpost75; 04-30-2020 at 05:57 PM.
The ENEMY is listening.
HE wants to know what YOU know.
Keep it to yourself.
That was informative Outpost75 thanks for posting it.
It is sad to hear but informative. Do you think it is any better now? And what manufacturer do you think produces the best quality ?
I had no idea Brian had such an engineering background. He never mentioned it in any handloader article I've read. That's good to know.
And the can of worms is opened...
Yup I have no illusions I buy very few revolvers that I am satisfied with stock S$W or Ruger but am usually able to fix or get fixed to suit me. I have had better luck with autos but have had some issues with them to.
My hands-on experience in that sort of testing ended in 1988.
I can't and won't comment on current product quality.
Suffice to say that an old gun that "works" is worth more than a new one which doesn't.
The ENEMY is listening.
HE wants to know what YOU know.
Keep it to yourself.
No wonder the older guns sell for higher prices.
Thank you from me as well, Outpost. That was very interesting. I had no idea that S&W had had that many problems.
I understand now why some of you guys cautioned me against a steady diet of magnum loads of any kind in my old Model 66, in my recent thread about working up a good .357 Magnum load. I will heed that advice. I wish Ruger would make a revolver with a feel and trigger more like a S&W. I've really tried to like Ruger revolvers, but I always find myself coming back to S&W.
Thank you Outpost. That is pretty much the steel critter shooters leaned early on in the revolver class. Rugers and Dan Wessons were the revolvers to beat.
"Come unto Me, all you who labor and are heavy burdened, and I will give you rest." Matthew 11:28
Male Guanaco out in dry lakebed at 10,800 feet south of Arequipa.
I've got an unmodified GP100 that will put many S&W triggers to shame. I can't imagine why either one couldn't become amazing with the right gunsmith. As for the durability of S&W, as I understand the K frame 357 magnum was basically intended for carry, mostly by police officers. It was a hotrod if you will. Now I am not S&W lover, I'm a Ruger guy all the way, but I have not heard of any durability problems with the N frame. I've seen no evidence a model 27 won't live at least as long as a Ruger GP100.
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
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
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