+p and +p+ loads in 9mm

[Duane Thomas]

I'm not sure how old 9mm Luger is, probably about 1930 or so

1902.

[twodownzero]

So you think that shooting 9mm major loads at SAAMI COAL would be "safe" in ANY modern 9mm, in consequence?

I think you're sadly mistaken. People HAVE blown guns up at the old power factor, that's precisely why USPSA banned 9mm Major. When they did decide to allow it, they lowered the power factor because at 165 power factor 9mm is questionable, and at 175-180, it's downright dangerous without careful handloading practices and "loading long."

The difference between safe loading practices and haphazard hacks blur significantly when an inexperienced handloader disregards book max and deviates off to uncharted waters. The only evidence you have that this is "safe" is that you haven't blown your gun up yet or heard too many stories of the same. Additionally, I think we all know that engineering factors exist, especially when you're talking about 40,000 PSI inches from your face and even less distance from your fingers. That does NOT make it a responsible practice to test just how big that coefficient might be by loading cartridges for which that firearm was not designed.

A proof load proves one thing: that the gun can withstand a somewhat substantial overpressure ONE TIME. It does not indicate that a steady diet of overpressure handloads are suitable OR safe when fed to a gun in the long term.

Driving a truck at twice its capacity might be done "safely" and without accident for years. That doesn't make it wise to disregard the ratings and operate that piece of equipment beyond its intended capacity. Safety factors exist because the dynamic world is different than the theoretical, static one. But that does not mean that we should try to find out how far beyond specification a piece of equipment will operate without injuring ourselves or others.

As responsible adults, we can recognize that our guns will protect us from overpressure loads and withstand loads well beyond their designed limits. It does not therefore follow that testing the limits is responsible or safe.

Every gun that blows up wasn't, of necessity, fed a double charge. Some loads are more prone to it than others, but pressure does not always increase linearly with charge weight and anyone who pushes beyond book max must do so carefully and slowly.

We simply don't have the data that ammunition manufacturers have and chasing proof pressure with our handloads is certainly a fool's game. If you want to recommend it, that's on you.

[G-ManBart]

So you think that shooting 9mm major loads at SAAMI COAL would be "safe" in ANY modern 9mm, in consequence?

I think you're sadly mistaken. People HAVE blown guns up at the old power factor, that's precisely why USPSA banned 9mm Major. When they did decide to allow it, they lowered the power factor because at 165 power factor 9mm is questionable, and at 175-180, it's downright dangerous without careful handloading practices and "loading long."

Your sequence of events is wrong. Also, people shooting 9 Major simply went to 9x21, loaded to the same OAL as they were using with 9x19, kept shooting 180+PF loads and guns weren't blowing up. They turned the 9x21 into a 9x19 by using the same amount of available case capacity, so the pressure was the same. Guns weren't blowing up.

Correct me if I'm wrong, but you weren't shooting USPSA back then, were you? You actually, personally, KNOW about a gun blowing up because of an overpressure 9 Major round?...not just "heard about it"?

Loading long doesn't change the pressure required to reach a given velocity. OAL simply changes the amount of powder that will be required to get to that given pressure level. So, load it long, short, medium, the pressure to drive bullet X, to velocity Y, will be the same.

The only evidence you have that this is "safe" is that you haven't blown your gun up yet or heard too many stories of the same. Additionally, I think we all know that engineering factors exist, especially when you're talking about 40,000 PSI inches from your face and even less distance from your fingers. That does NOT make it a responsible practice to test just how big that coefficient might be by loading cartridges for which that firearm was not designed.

Actually I have more than that. Hmmm....maybe some of those engineering factors even. There are a lot of guns built in both 9x19 and .357 Sig running around out there. They're made from the same basic parts, same construction of barrels and the only difference is how large the chamber is cut. One would think that they should both handle the same amount or pressure. In fact, the 9x19 gun should handle a little more because the chamber thickness is greater. C.I.P. lists a max pressure of 44,236psi for .357 Sig and a proof load for that would be 57,506psi. Using SAAMI numbers they would be 40,000psi and 52,000psi. A 9x19 Glock, or 1911 or anything else is going to be just as strong as that same gun in .357 Sig so running 40,000psi in the 9x19 isn't suddenly going to make those guns explode...not even close.

A proof load proves one thing: that the gun can withstand a somewhat substantial overpressure ONE TIME. It does not indicate that a steady diet of overpressure handloads are suitable OR safe when fed to a gun in the long term.

Actually, a proof test involves two shots, not one. Then they take the gun and examine it by various methods, magnafluxing, sectioning etc to make sure that those two shots didn't cause metal fatigue, or other problems. Most manufacturers conduct destructive testing to insure they have a safe margin above and beyond things like proof loads.

Driving a truck at twice its capacity might be done "safely" and without accident for years. That doesn't make it wise to disregard the ratings and operate that piece of equipment beyond its intended capacity. Safety factors exist because the dynamic world is different than the theoretical, static one. But that does not mean that we should try to find out how far beyond specification a piece of equipment will operate without injuring ourselves or others.

As responsible adults, we can recognize that our guns will protect us from overpressure loads and withstand loads well beyond their designed limits. It does not therefore follow that testing the limits is responsible or safe.

Every gun that blows up wasn't, of necessity, fed a double charge. Some loads are more prone to it than others, but pressure does not always increase linearly with charge weight and anyone who pushes beyond book max must do so carefully and slowly.

We're not talking about trucks.

You keep talking about guns blowing up. When guns "blow up" it is almost always something like a Glock KB, which is not caused by overpressure rounds, but that's another story for another time. I've seen a couple of case walls let go, with no real damage. Actual metal failing is extremely rare, and I have yet to see that happening with something like an Open gun running Major loads (of any kind). I have seen one that blew out the primer, create a lot of smoke and noise, but that gun finished the match with all it's parts intact. I saw it a year later and it was still running fine.

Nobody said to completely disregard book loads and just wildly do something stupid, but you started out essentially saying +P+ was super dangerous and shouldn't be attempted, etc, etc. I'm just saying that's not necessarily true. It can be done, and done safely. Lots of folks are doing it, and have been doing it for years, without problems. R,

We simply don't have the data that ammunition manufacturers have and chasing proof pressure with our handloads is certainly a fool's game. If you want to recommend it, that's on you.

[Morgan]

Loading long doesn't change the pressure required to reach a given velocity. OAL simply changes the amount of powder that will be required to get to that given pressure level. So, load it long, short, medium, the pressure to drive bullet X, to velocity Y, will be the same.

Not exactly true. Loading longer reduces the PEAK pressure, or spike, which is the main reason cases (and guns) fail. Try loading Clays short in .40, reducing the powder charge to get the same velocity as a long-loaded .40. Guess which cases will blow (and guess how I know).

[Nik Habicht]

I think you're sadly mistaken. People HAVE blown guns up at the old power factor, that's precisely why USPSA banned 9mm Major. When they did decide to allow it, they lowered the power factor because at 165 power factor 9mm is questionable, and at 175-180, it's downright dangerous without careful handloading practices and "loading long."

USPSA never banned the 9mm from making major. It did, for a few years, require a cartridge OAL of 1.250 to make major with the 9mm. Then the power factor got dropped from 175 to 165 to make major, and a few years after that event, the board was persuaded that 9mm could safely be loaded to major at normal 9mm OALs by carefully considering loading and chrono data and the availability of factory produced 9mm that would make power factor.

It wasn't easy to convince the board -- they wanted to see a lot of evidence....

[Mr. Chitlin]

Police departments are not issuing +P+ as such a standard does not exist.

I have a couple of boxes of Federal Hydra-Shok 9mm +P+ marked Law Enforcement Only sitting on my shelf. Our local PD issued them until they went to 40 SW.

[Duane Thomas]

USPSA never banned the 9mm from making major. It did, for a few years, require a cartridge OAL of 1.250 to make major with the 9mm. Then the power factor got dropped from 175 to 165 to make major, and a few years after that event, the board was persuaded that 9mm could safely be loaded to major at normal 9mm OALs by carefully considering loading and chrono data and the availability of factory produced 9mm that would make power factor.

It wasn't easy to convince the board -- they wanted to see a lot of evidence....

The "9mm Major/9mm +P+ is flat unsafe to fire" argument is old and tired, that's for sure. I thought we settled this years ago, but I guess some people didn't get the memo.

[twodownzero]

USPSA never banned the 9mm from making major. It did, for a few years, require a cartridge OAL of 1.250 to make major with the 9mm. Then the power factor got dropped from 175 to 165 to make major, and a few years after that event, the board was persuaded that 9mm could safely be loaded to major at normal 9mm OALs by carefully considering loading and chrono data and the availability of factory produced 9mm that would make power factor.

It wasn't easy to convince the board -- they wanted to see a lot of evidence....

The "9mm Major/9mm +P+ is flat unsafe to fire" argument is old and tired, that's for sure. I thought we settled this years ago, but I guess some people didn't get the memo.

I hope you're not directing that at me (I'm not saying you are).

I don't think that carefully loaded +P+ or 9mm Major is unsafe to fire. I do think that recklessly loaded 9mm ammo beyond SAAMI specs is a recipe for disaster. If you want hot loads, asking in the beginner's forum probably isn't the best place to start.

[Duane Thomas]

True. That's not what I've gotten from your previous posts - but true.

[smokshwn]

I think you're sadly mistaken. People HAVE blown guns up at the old power factor, that's precisely why USPSA banned 9mm Major. When they did decide to allow it, they lowered the power factor because at 165 power factor 9mm is questionable, and at 175-180, it's downright dangerous without careful handloading practices and "loading long."

In order to make sure I make PF when chronoed and as a factor of the guns behavior I run my 9mm loads at around 175-180 powerfactor with a COAL of 1.15. After pretty close to 50k rounds I would say they are far away from being questionable and to suggest that they are "downright dangerous" is way off base.

Regardless of the cartridge or the load, sloppy handloading is dangerous that goes without saying. Using it as a qualifier makes no sense. As to loading long, pressure is pressure regardless how "long" I load.

You may not be comfortable loading 9mm to the above listed criteria, but please let that be a factor in your statements rather than infering that those of us who do are somehow dangerous, careless, etc.

[Duane Thomas]

One thing that always seems to get overlooked in discussions like this is that the 9mm Parabellum casing has attributes that make it actually one of our safest cartridges to hotrod. For thing the small interior capacity means you CAN'T double charge the casing; powder will actually overflow the casing if you do that, making it very obvious the double charge happened, and if it does you literally couldn't seat a bullet anyway. Also there's a reason the original and current European specs for this cartridge are able to run at +P+ pressures: the 9mmP is an ungodly strong little casing, with a very thick web. I'm not saying it's impossible to blow a 9mmP casing, but man, you'd have to work really hard at it.

[twodownzero]

As to loading long, pressure is pressure regardless how "long" I load.

I'm glad we've established "pressure is pressure." Tautology will get you nowhere in an analytic discussion.

Pressure, more correctly, is Force / Area. So, you can get more "pressure" by increasing "force" or decreasing "area." Guess what that means if you create the same pressure in a smaller area (shorter COAL)? Yep, you guessed it...more "force" is being applied.

Telling newbs how to hot rod their 9mms is certainly not the intent of the beginner's forum. If someone has the skill to safely load a gun to 180 pf in 9mm Luger, they certainly aren't asking here and doing so without working up.

Edited February 6, 2010 by twodownzero

[Nik Habicht]

I am going to go ahead and use this as a good place to call a time out on this thread.....

We've beat similar topics around a couple of times, IIRC. We always get about the same opinions and divided points of view.

I am going to close it for a day or two, just because the opinions are getting a bit heated. Somebody remind me to re-open it if there is something new to add.

TIME OUT.