9mm +P+ Ammo

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bearmn56

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Which Gen3 pistols can handle this ammo? Seems to be more and more of this higher pressure ''self defense'' ammo out there from the major manufacturers and specialty loaders like Underwood. Bill, Montana Territory
 
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My thoughts are why subject the firearm to the increased wear & tear of over-pressure ammo when testing shows that the terminal ballistic performance of these loads is rather lacking when compared with the standard pressure heavier bullet loads.

See here and note the degree of bullet expansion and depth of penetration particularly of the Winchester 147gr RA9T and the Federal HST 150gr loading in comparison to the rest.
https://www.luckygunner.com/labs/self-defense-ammo-ballistic-tests/#9mm


Cheers
Bill
 
This was recently discussed in the ammo forum at +p 9mm .

Since there is no spec for +P+ no gun manufacturer will say it is OK. It would be like signing an open check. Even if the current crop of +P+ ammo is fine in M&Ps there is no way for S&W to know if some boutique ammo maker might make even hotter loads labeled +P+ in the future.

I would stay away from +P+ loads. While increased wear is a risk most people will not shoot enough for that to be a problem. The bigger risk is that a gun designed for regular and +P pressure specs might not be as reliable when fed ammo that exceeds those pressure limits.
 
BMCM said:
My thoughts are why subject the firearm to the increased wear & tear of over-pressure ammo when testing shows that the terminal ballistic performance of these loads is rather lacking when compared with the standard pressure heavier bullet loads.

See here and note the degree of bullet expansion and depth of penetration particularly of the Winchester 147gr RA9T and the Federal HST 150gr loading in comparison to the rest.
https://www.luckygunner.com/labs/self-defense-ammo-ballistic-tests/#9mm


Cheers
Bill
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But ... But ... I don't expect to ever be attacked by ballistic gel!!!!!:eek:

OP: I've got a small stash of Federal 115gr. +P+ I shoot on occasion, but it does seem that there's a lot of wear-and-tear reported, for not all that much gain when defending oneself against ravening cubes of jello....:p

It's probably not horrible for the gun - but why bother? :D
 
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The W-W 115 JHP +P+ was 40,000 cup. When we were issued the 5904 one of our range guys decided to document every round fired thru his 5904 to see how long it would last. When he retired he had a documented 80,000 rds thru his stock 5904. Only thing he had done was replace springs and replaced the barrel at about 50,000 after accuracy started dropping off because the rifling was so worn. Not saying every 5904 will run that long on +P+ but at least 1 did that was documented number of rds.
If you can afford to shoot 80,000 of +P+ then the price of a 5904 is not a factor.
 
I think the Illinois State Police ran tons of +P+ 9x19 through their 39-2 and 439 pistols without problems. The S&W pistols are very well built and will withstand such ammo. With modern hollow point bullets, +P+ pressures are no longer required for reliable expansion. In fact, with modern bullets +P gets only slightly better expansion, but at the expense of decreased penetration.
 
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Thanks to BMCM on the link to the Lucky Gunner 9mm & 40s&w ammo tests. I looked the info over carefully and took some notes. Now it's time to go to the local sporting goods stores and see what is actually available. I have always been a fan of heavier per caliber bullets. However, I purchased 500 40 caliber 165gr HAP bullets on Gunbroker. Have been working up some loads using Longshot. With published loads I have been getting some good velocities. These bullets have a reputation for good expansion. Have loaded lots of plinker 9mm.....but with commercial plinking ammo available at around 15 cents a round, I just don't bother. My carry 9mm ammo will undoubtedly be commercial stuff....strongly influenced by the Lucky Gunner tests. Bill, Montana Territory
 
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If you look at the generic S & W semi-automatic pistol manual of the era, it states + P (because there is a standard measurement for this) is OK but will accelerate wear, and + P + is not recommended. This type of information makes sense from a mechanical, legal and warranty standpoint...not to say you can't use it, but the upside from + P seems minimal. Good luck in your ammo selection.
 
BigBoy99 said:
Why not go the .38 Super caliber? That is 9mm with a longer case?
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Because it doesn't fit in 9mmP firearms? :p

Maybe something could be cobbled together, at great expense, using a 45XX frame and slide, but I think you'd have to be having a custom barrel made. Probably magazines, too.

Likely not worth the expense for the smallish improvement in ballistics.
 
Muss Muggins said:
Lots of people gonna show up soon and tell you there's no such thing as +p+ ammo. It'll be fine to shoot . . .

(ducks and covers . . . )
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Relax, there are lots of +P+ loadings, and most are safe to shoot in well-made modern arms. What is missing is a universally recognized pressure standard for +P+, so the ammo manufacturer sets their own standards, and you need to know what that is to make an informed choice.

Some GIs got their hands on some obscure +P+ made for submachine guns and blew the slides off early M9 Berettas, right into the shooters face. There is no guarantee that any given +P+ will be safe in your gun, so it is a case-by-case risk.
 
Update...took my notes on 9mm ammo from the Lucky Gunner tests to some local sporting goods stores....none of the better 9mm SD rounds to be had...they just don't carry them. Hmmmmm....so, I searched on Gunbroker for some components. Spectre supply had 147gr 9mm HST bullets for sale for about 10 cents delivered, in lots of 500. Got some coming. Also, found 500 fully processed, ready to load, FC 9mm nickel casings for 8 cents delivered. Hogdgon's reloading data center says I can get about 1000fps using Longshot and this bullet from a 4" barrel. This is with STANDARD pressure. Load development is in my future! Bill, Montana Territory
 
Uh, guys.............+P+ ammunition originated in the dim, dark days before reliable expanding bullet designs. The only way they had back then to make the current bullets expand was to drive them faster. They also didn't have the powders that are widely available tody.

The currently available products by major manufacturers at lesser pressures will work fine for your purposes. They're the one's who win law enforcement ammo bids. Remember where you put the bullet is much more important than diameter, velocity, pressure or trendiest design/ad campaign. Speaking of which, the HAP bullet is NOT designed for expansion, at least according to my latest Hornaday catalog.

FWIW, 9 x 19 mm+P is pretty much the same as European 9mm/9mm NATO.

There are any number of online ammo sources for those whose LGS doesn't stock certain items. Ammunition to Go, Ammoman, Midway, Streicher Police Supply, etc.
 
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It looks like that one can achieve factory ballistics without any exotic +p+ handloads. Hodgdon's posts some very nice data in their loading data center. I just bought 500 147gr 9mm HST bullets at about 11c each and 500 FC nickel brass for about 8c. With standard published loads, I should be able to get at least 1000fps with the 147 HST in a 4" barrel (and only a little less in a 3.5" barrel). This should allow me to duplicate factory 9mm HST ammo.....at about 25c per round (instead of some 70c). Lots of cheaper practice and no extra wear and tear on my 909, and 3914 Ladysmith (and other unmentionable 9mms as well:) ). Bill, Montana Territory.
 
FYI....I posted a thread on the Reloading board about reloading the 9mm 147gr HST bullets. Good results and no difficulty making factory ballistics. Bill Montana Territory
 
Mike said:
If. More horsepower is wanted, why not just buy a bigger gun.
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This. If you want more power, then just take your M&P9 to your LGS and trade it for an M&P40 or M&P45. The M&P40 they may even be willing to throw in some ammo for to sweeten the deal (depending on the popularity of .40 S&W in your area) since 9mm is more popular these days.

Honestly, all running +P+ ammo through your M&P9 is going to do is wear it out a lot faster, with equal or greater recoil than a .40cal.

+P ammo in general is basically just the futile attempt to make a cartridge into something it's not. If you start to think that +P let alone +P+ ammo is necessary, then you might as well just stop right there and begin seeking a more powerful cartridge.
 
Mike said:
If. More horsepower is wanted, why not just buy a bigger gun.
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While revisiting this thread, I remembered reading years ago in Cooper on Handguns, mention of the Super 9. Col. Cooper built his on a Colt Lightweight Commander (not surprisingly.) He used trimmed .223 cases, almost identical in dimensions to the 9x19. He had a barrel made and said he had to modify the extractor to catch the rim in a satisfactory manner without any further modifications. The picture provided showed a 1911 with a barrel extending beyond the front of the slide. Without specifics, he noted velocities in the .357 range. He didn't talk about specific powders, either. I suppose with the modern powders available, some pretty warm handloads could be cooked up.
A web search turned up some additional info and a cool mag cover pic.
 

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To all. I DO have several 40 S&W pistols, including some S&W 3rd gens. I have a 4040PD, a 4006 and a 4013. The 4040PD is a sweetheart and is the same size as my 3914 Ladysmith. The 4040PD is a real powerhouse...especially with Corbon's Pow R ball ammo. Just searching for a good reliable SD load for the 9mms. Bill Montana Territory
 
Dirty Harry Callahan said:
Honestly, all running +P+ ammo through your M&P9 is going to do is wear it out a lot faster, with equal or greater recoil than a .40cal.
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Aren't the 40 and 9mm M&Ps pretty much the same gun? I am not even sure if the 40 has a stronger recoil spring. If the 40 model has about the same recoil as a 9mm +P+ I would expect it to wear at about the same rate. The +P ammo is only 10% higher pressure and I do not think that is going to hurt anything on an occasional basis.

In general I strongly agree with buying a bigger gun if you want more power. But I do use +P (not +P+) GoldDots in my 9mm carry gun. Some brands of 9mm FMJ practice ammo seem to be loaded to -P power levels. Hopefully that does not carry over into carry ammo but buying +P increases the odds I have ammo that is loaded up to, but not over, the limit for 9mm. I don't want ammo that tries to turn the 9mm into a .357 Sig but I also don't want ammo that is loaded down to .380.

ETA: Even the weakest 9mm is stronger than 380 and even the hottest +P+ load Underwood sells is less than a .357 Sig. I got a bit carried away. But while 9mm +P seems really hot compared to say Winchester White box the gap between NATO spec and +P is not nearly as large. The NATO spec is not +P, it is just loaded to the SAAMI limit. For some reason while ammo makers will make weak practice FMJ ammo for 9mm, 10mm and 45 even practice 40 S&W seems pretty hot.
 
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I have tried some of Corbon's Pow R Ball in 9mm. This ammo is loaded HOT!! I have tried loading some of the fired nickel cases and found that there were some expanded primer pockets. Also, some show chamber imprinting on the fired case and leave a distinct ring at the base after the cases are resized. Chrony results show that the 100gr (I think that is the bullet weight...I threw away the empty boxes) traveling at 1340fps average in the Ladysmith's barrel length. Shoots OK but I now throw away the cases after firing. Since I only carry this ammo and don't regularly shoot it, I am not particularly worried. Never had a FTF or FTE. Bill Montana Territory
 
FWIW, I've used a fair amount of Winchester and Federal 9mm +P+, and a smaller quantity of Remington +P+, is a variety of semi-autos, including 3rd. Gen. S&Ws, and revolvers without issue. I can't advise others what is safe or not in their firearms, but just share my own experience with +P+.

I saw Col. Cooper's Super 9 in the armory at Gunsite years ago. Along about '85, I did some Super 9 experimental loading myself, using .223 cases trimmed to .900" in a 5" .38 Super barrel that headspaced on the case mouth. The Colonel's gun had a 6" or so barrel, so I never equaled the published ballistics achieved with his gun. I did get to 1625 FPS with a 115 grain JHP before deciding not to push my luck my luck further. I used Win. 571 powder, and Federal rifle primers, and didn't run into any issues, but 115 @ 1625, in a 5" barrel, satisfied my curiosity about what might be safely achieved with the Super 9. I suspect the Super 9 generated pressures much higher than 9mm +P+, probably similar to factory 9X23 Winchester pressures.

BTW, Reference 9mm +P+, where much concern is expressed anytime it is mentioned, CorBon 9mm +P routinely achieves chronographed velocities as high or higher than major U.S. manufacturer 9MM +P+ in my guns. For instance, in a Dan Wesson 9MM with 5" barrel, Federal 9mm 115 grain +P+ averaged 1336 FPS; CorBon 115 grain +P averaged 1440 FPS. In a Ruger 3" revolver, the Federal +P+ averaged 1313 FPS, the CorBon +P averaged 1419 FPS. The CorBon tested was not that produced under CorBon's new ownership, so I don't know how current CorBon ballistics compared with the older CorBon ammo. Anyway, I wonder if +P+, even though there is no established standard, is loaded to pressures significantly higher, or any higher at all in some cases, than than +P ?
 
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Lets talk pressure. Years ago, before ballistic software, the Powley Computer slide rule was the available tool. One of the rules of thumb published with it was the axiom: For every 10% increase in pressure, there was only a 5% gain in velocity. So, lets look at Underwood +P+ 147gr 9mm ammo. Standard max pressure for the 9mm is 35,000psi. Plus P (+P) max pressure is 38,500psi....a 10% increase. Standard 147gr loads produce about 1000fps in a 4-5" barrel. +P loads produce about 1050fps in the same barrel length. This follows the axiom of a 10% increase in pressure producing only a 5% increase in velocity. In one Youtube video on the Underwood +P+ 147gr loading, the velocity was about 1150 fps. This represents a 11.5% increase over the "standard pressure" 147gr loadings. In order to produce an 11.5% increase in velocity the pressure would have to be twice that or about a 23% increase in pressure over standard. So, 35,000psi X 23%=8050psi INCREASE. 35,000psi + 8050psi= 43,050psi calculated operating pressure. These figures may not be precisely accurate, but it does give one some idea of the magnitude of the pressures generated to give those inflated velocities. I don't know what pressures PROOF loads generate, but they might not be a great deal higher than these calculated pressures. Bill Montana Territory
 
+P+ is generally considered to mean the pressure exceeds that of accepted industry specs for +P, but that's all it means. There's no official "upper" industry limit, so there's no way to know by how much the pressure exceeds the commonly used industry standards. Buyer/user beware.

Back in the early days of my S&W armorer training we were told to use whatever issued ammunition was provided by our agency ... with the presumption being that any +P and +P+ 9mm ammo used was going to be produced by one of the major American ammo makers who provided contract ammo to LE/Gov agencies, and who had a vested interest in not blowing up the common major maker pistols used in LE.

Back then it was also common for LE buying higher pressure ammo to sign a waiver accepting responsibility for using the higher pressure ammo, meaning any increased wear & tear, etc.

It's also a really good idea to consider any warnings or prohibitions offered by a gun maker when it comes to the ammo the gun company considers appropriate or inappropriate for use in their gun. ;)

We were also told that the use of such +P+ 9mm ammo could not only accelerate normal wear & tear, but to watch for deformation caused by the higher recoil forces propagating throughout the pistol.

One example which we were specifically told to be alert to seeing was the possible deformation of the 3rd gen pistol slide stop lever assemblies. We were told that the increased recoil forces might result in the eventual outward or inward change of the angle of the slide stop lever in relation to the assembly's frame pin. In other words, the original 90-degree angle of lever-to-pin might increase or decrease, potentially causing different functioning problems at some point.

Back in those days we were taught how to use a vise and lead babbitt bar to "adjust" (judiciously whack) the angle and restore it, if necessary. Later on the instructors just told armorers to replace a tweaked slide stop assembly with a new one. The inference seemed to be that the factory may have decided that some armorers might lack the skill and experience to properly "adjust" an assembly, which is understandable when you remember that only being a factory trained armorer is NOT the same thing as being trained as a gunsmith. It was also a lot faster to replace an assembly than to spend bench time trying to "adjust" one, and the assemblies were inexpensive (sometimes free) and plentiful back in those days. Why waste bench time that might be useful for some other need, right?

Since the factory can't know what +P+ ammo is going to be used, it's easier (liability-wise) to just say that it's not approved for use.

Now, in my last Glock recert class, we were told that when the factory test-fires each new Glock, they use 2 standard pressure rounds and 1 proof round, and the definition of "proof round" meant 130% of standard pressure.

After the Shield 9 had been released for a while, I was told by a couple of different factory folks that while the use of +P was acceptable for use in the Shield 9 (albeit that it would accelerate wear and tear), the use of +P+ ammo was NOT approved.

In my last Glock class a Glock employee said that the G43 could be used with +P+ ... but then later on I heard from someone else in the field that they'd recently been told by Glock that the use of +P+ in the G43 wasn't recommended, and the reason seemed to be that it could cause increased slide velocities that might lend itself to feeding/functioning issues.

Now, I was issued 147gr standard pressure, 124gr +P and 127gr +P+ duty ammo at various times throughout my career when I carried S&W pistols. I used that ammo in all of my S&W and Glock pistols, and still do. I also replace recoil (and other) springs at shorter intervals and inspect for any signs of increased wear and tear of parts and assemblies.

One of our members here used to work for ISP, who used the pioneer major maker 115gr +P+ loads for many years as a duty load in S&W aluminum-framed pistols.

Now, personally, I've come to avoid using anything labeled +P+ that isn't made by one of the major American ammo companies who have invested a lot of years of R&D and have acquired a lot of successful experience in the production of +P+ duty ammo for LE/Gov agency users.

I tend to consider the +P+ designation for 9mm (and .38SPL) ammo as meaning something akin to "Here Be Dragons" in the margins of old world maps. You know it's higher pressure than +P, but you don't know by how much ...
 
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Fastbolt, What a great post. I just ordered new recoil springs for my 909 and 3914 Ladysmith from Wolff. I ordered them 2lbs over stock. Also, I worked up a handload using the Hornady HST 147gr 9mm bullets using the nickel FC cases. I put all this in a post over in reloading. Bill Montana Territory
 
bearmn56 said:
Fastbolt, What a great post. I just ordered new recoil springs for my 909 and 3914 Ladysmith from Wolff. I ordered them 2lbs over stock. Also, I worked up a handload using the Hornady HST 147gr 9mm bullets using the nickel FC cases. I put all this in a post over in reloading. Bill Montana Territory
Click to expand...

Thanks.

Something to consider about the use of heaver-than-factory rating recoil springs.

Aside from the variable tension recoil springs, heavier rated recoil springs can mean the slide/barrel is being slammed forward harder than with a standard rated spring. In the S&W 3rd gen guns, especially with aluminum frames, that means the barrel is going back forward against the slide stop lever pin and hitting it harder than it may be with the standard strength spring.

That "shock" is going to be not only transmitted to the frame hole for the lever assembly's pin in the aluminum frame, but it's going to be transmitted to the rest of the slide stop lever assembly. I suspect that this may have been involved in how recoil & cycling force (shock) could cause the slide stop lever body to potentially deform and acquire an inner or outer "bend" when the hotter loads were used.

I can't know how much harder a heavier-then-stock recoil spring might slam a slide and barrel forward back into battery, but if it's "enough" harder to help ensure a fouled pistol continue to go into battery, it's probably lending some added force to the process. If the bottom lug of the 3rd gen barrel is going forward and hitting the slide stop lever assembly frame pin harder, might it risk transmitting enough extra force to increase the wear and tear on the frame's pin hole and/or the slide stop (via force transmitted from the impact against the pin)?

Balancing recoil spring ratings is something engineers devote time and attention to doing. Slide velocity is an important influence when it comes to "feeding timing", and it can even have an influence in ejection timing.

I once had an interesting conversation with a manager at the Ruger Prescott plant about how heavier recoil springs used in the P90's could reach a point where they were more likely to cause brass being ejected to the shooter's face, due to the slower "timing" of the slide's rearward travel and how the extractor had more time to hang onto the case rim as the ejector was kicking it outward. Our conversation had been prompted by me having some questions about errant ejection issues with some 200gr .45ACP +P loads of that time.

At that time they'd recently bumped up the recoil spring in their P90 by a pound or two (it's been so long I don't remember), and he was going to send me a couple. He said their engineers had decided to increase the recoil spring rating because of some customers reportedly trying to "magnumize" (his words) their P90's, but he also offered to send me a P91 recoil spring (their early production .40 in the metal P-series line) to try.

He warned me that the stout spring used in the P91 was so heavy that it might aggravate the errant ejection and cause even more brass to come back at my face due to the slower cycling and longer "dwell time" of the extractor holding onto the case rim. Boy, was he right. ;)

Now, I've always used slightly heavier recoil springs in my 5" Gov and 4 1/4" Commander 1911's. I even experimented with heavier recoil springs in my S&W 3rd gen guns, but I've long since returned to using stock rated recoil springs in my own 3rd gen's.

Not anyone's "expert" in this regard, nor am I a licensed gunsmith. I'm just a LE instructor who has seen some range and bench time, and who has listened carefully to a lot of people from some of the different gun companies over the years for which I attended some assorted armorer classes.

Balancing recoil spring rates is something, in my opinion, to be approached cautiously. It can affect things in the operation and functioning of pistols. (And in some potentially different ways, depending on whether we're talking hammer or striker guns, too.)

Best regards. :) Nice hearing from you.
 
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