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Discussion Starter #1
The velocity stated in the Federal page of Federal Hi-Shock (9BPLE)+P+ 9mm 115 gr. jhp is 1300 fps, why is slower than the Cor Bon (SD09115) 9mm +P 115gr. jhp 1350 fps and much slower than the Double Tap GD 9mm +P 115 gr. jhp at 1415fps?? Shouldn't the higher +p+ pressure drive a same weight bullet faster?
 

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Ok... let's start with defining "+P".

SAAMI defines the operating pressures in which a load should operate. For example, 9mm standard pressure has a 35,000psi ceiling if I remember correctly. So if one had a load which operated at 35,500psi, it would have to be designated "+P".

Some companies have found ways to get +P+ (no SAAMI spec, just anything above the "+P" ceiling) out of +P loads. I believe Cor
 

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Hello. It has to do with pressure and what powder is being used. These loads were developed in different times and use different non-cannister blends of powder. As new powders and blends became available, we see different loads that can be more efficient in obtaining bullet velocity at lower pressure.

Perhaps an easier way to visualize this is to look a reloading manual. You will see powder charges for different loads and the approximate velocity expected for that charge, but not all of the powders will go all the way to the highest bullet velocities. Some will show a maximum charge well before maximum possible velocity is reached due to pressure. Where they max out might well be considerably below the maximum possible velocity with another powder.

If a load is being specifically made for a law enforcement agency, there will be certain parameters set and often requiring certain accuracy expectations from a given make/model handgun. I may very well be remembering incorrected but I think the Federal 115-gr. JHP +P+ load mentioned was originally intended for the Illinois State Police and the Model 39. The load probably met the requirements for use in that pistol.

Best.
 

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Further evidence that +P doesn't necessarily mean higher velocity in a given gun:

I measured velocity in my Kahr P-9 using several 115 gr bullets. Interestingly I found that CCI Blazer FMJ 115 gr (the aluminum case stuff) and Speer TMJ Lawman 115 gr had higher speeds (and lower standard deviations!) than Corbon 115 gr DPX. Speer GDHP 115gr was almost identical in velocity, just a tad lower, again with a lower standard deviation.

The P-9 has a shorter barrel, I think it is 3 or 3.5 inches. I thought that the barrel may be too short to give Corbon's increased pressure enough time to push the bullet up to higher speeds. However, when I fired the same four ammo brands out of my Hi Power, with the 4.5 (approx) inch barrel, I found pretty much the same thing, except that now the Speer GDHP 115 gr was definitely faster than the Corbon. This time Corbon showed a tad more consistency than the Lawman round, but was behind the other two. (The Speer GDHP showed the best consistency in both handguns).

Of course, I didn't run large amounts of ammo broaden my statistical base - I usually shoot 10 rounds and then find the average velocity and standard deviation -- but the the fact that the same pattern held true with both my pistols leads me to believe that whatever Corbon's increased pressure does for the DPX round, increased velocity isn't it.

So this really doesn't answer your question -- "Why is this so?"-- maybe it just reinforces your confusion! Sorry!

elb
 
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Discussion Starter #5
It doesn't make sense to me that ammo manufacturers use a powder that increase the pressure to +p or +p+ levels only to be slower than a standard round....
 

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Howdy ididdp5,

Again this may not directly answer your question, but I thought I would throw it into the mix.

Something I will often see stressed in reloading manuals, reminded me of this comment. Ammo companies are sort of trying to walk a fine line with their products. Not only are they making the rounds to be fired in the newest and perhaps the strongest weapons out there. They are also making a round that can be fired from an older weapon, that perhaps has just been acquired by the current owner. The new owner has not backgroud into how well the weapon has been cared for, but he wants to shoot his new acquisition and expects factory ammo to work properly for him.

This is just my personal opinion with no "evidence" to base it on either. Just more of a thought. I question if some manufacturers simply call a round +p or +p+ simply to stay up with the competition at times too. During some recent testing with a new chronograph, like ELB noted, shooting 357 Sig loads in both a P226 and P229, the Gold Dots out performed the Cor-Bons, which was not what I was expecting.

I really am not sure there is such a creature as the "magic bullet" out there, as if I had found it I would sure be singing its praises to the masses. I take the position if I place the round where it belongs, the average JHP bullet will do what is intended of it. Some may well do it better than others to be sure.

When I am testing different bullets for a new handgun, I simply stick with a few perferred loads, and see which tend to be the most accurate in my pistol and function with total reliability. In a well designed round, I doubt seriously if the bad guy is going to be able to tell the round was moving 50-100 fps faster or slower when it hits the proper area.

Based on that I simply do not spend a lot of time worrying about +P or +P+ designations on headstamps. I want a round that is both accurate and reliable in my pistol. That is what is more important to me.

Again, while it does not really answer your original question, I hope it at least gives you more information to consider in making your ammo choices too. Good luck in your search.

twoguns
 
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Discussion Starter #7
"I question if some manufacturers simply call a round +p or +p+ simply to stay up with the competition at times too."
thanks twoguns! It now starts to make sense to me... :)
 
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Discussion Starter #8
Posted on the late (and lamented) www.fnhipower.com forum:

"In any given gunfight, there are a multiplicity of factors that dictate its outcome --- the "stopping power" of the load in your personal defense handgun only being a very small one. As fascinating as I find Marshall and Sanow's statistics, whether your handgun load rates 91% vs. 96% one-shot-stops (quoting the best loads for 9mm and .40 S&W on the above-referenced website) is very unlikely to influence whether you come out the winner or loser.

. . . . . the danger, for us personal defense-types (the vast majority on this forum), is that we can become fixated with the subject at the expense of much more important issues such as basic marksmanship, gunhandling, tactics, mindset, and the use of deadly force according to the laws of your state."


I am not provoking an argument between Marshall and Sanow's street-shooting statistics vs. shooting gelatin and other media vs. probing cadavers on a marble slab vs. etc. vs. etc. This issue has been "beat to death" on this and other forums and everybody has their own opinions, but just to point out that it's easy to become fixated with very, very minor "shades of gray" between different types and brands of ammo when we should be focusing on other areas of street survival.

. . . . . .my $0.02 ;)


P.S. I know discussing ammo and its alleged performance is fun and it's not going to stop, nor should it.
 

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as your moderator I'm not supposed to "butt in" unless rules have been violated. No rules have been broken on this thread so far and the discussion is eye opening. So I'll butt in by saying it seems, from the discussion, +p+ at present has two purposes...one is to provide certain LEO organizations with special ammo they need in their work....and the other reason as a marketing method to sell ammo. Many uniformed people out there don't consider "placement" and practice as the important facts of self defense and think a magic bullet, such as +p+ is going to "blow away" the villian, like in a Hollywood movie. Probably more folks like that than us so the market for +p+ is there.
As already pointed out there is no SAAMI data for +p+ and some loads rated that way could even be dangerous in a very old handgun . So just my opinion, +p is good enough, find ammo that functions 100% in your handgun, with good accuracy, practice with it until you feel confident.

If you find some +p+ that you like even better, fine, that's your choice.

Cheers,
og
 

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Mr. OG,

Well said sir, +1. If you don't mind I will take your suggestion and expand on it a bit.

My agency at one point was issuing the 9mm Gold Dot in standard, +P (both 124gr), and +P+ (115 gr) loadings. In short order we came to discover the +P+ load was damaging the roller blocks in our MP5 sub guns. At that point we did away with the +P+ option as a duty round.

I consider the MP5 a fairly robust weapon, especially when compared to many pistols available. So if it will quickly begin to damage an MP5, what will it do to many pistols if fired consistenly in them? We had a certain percentage of the office at that point who were saying hand me the +P+ for my pistol, I want the hottest round possible. Personally I feel no need to find out in one of my pistols.

I have to agree with both you and nevadaalan too, that far too many LEOs and John Q's spend too much time looking for the mythical "magic bullet" and not enough time practicing with their weapon using a round they can consistently shoot well with zero malfunctions.

While I like both the standard and +P Gold Dot 9mm loads, I personally don't see a great deal of difference between the two in terms of downrange performance. In my opinion, if either is placed where they belong, the odds favor the bad guy will not be able to tell the difference in velocity between the two rounds. So if someone feels they handle a standard velocity load better than they do a +P load, in terms of quicker recovery and tighter groups, that is the round I would suggest they use and practice with.

I am not trying to endorse Speer Gold Dots as the perfect carry round. Although it is often what is loaded in my pistols - that is after a great deal of testing in that pistol with that round. The same downrange performance in my opinion will largely be offered by any of the major brands of ammo in either their standard or +P loads.

As a 3.5 decade LEO, I do have a great deal of respect for my profession and those willing to serve in that capacity. But to be honest, in recent years I have noticed a trend where co-workers turn down practice ammo offered to them during quarterly quals as they "don't have time to practice". There are far too many folks I work with who simply shoot 4 times a year when required to demonstrate a passing score. While some do well, some also manage to barely shoot the minimum score. Personally, I do not want those minimal score folks standing beside me in a situation that has suddenly gone south.

The sad truth is that many civilian shooters clearly practice more often than at least some LEOs do. That fact will always be a mystery to me too. But good for the civilians anyway. I think the public perception is that all LEOs are very gun savvy too, which simply is not the case. I was recently drinking coffee during a first meeting of a manager in a large police department in my state.

They had recently replaced their duty weapons with a 40 S&W Glock. While he sat on the committee that made this selection, he was not able to tell me the model number of the pistol holstered on his side. When I attempted to question the rationale behind selecting the Glock over other brands, he stated that was easy. In their contact with other departments, they had been told that the Glocks seemed to work the most reliably when not cleaned frequently. That was both an eye-opening and depressing conversation for me.

Any weapon to me is a tool, and will do its part to protect me, if I do my part to properly maintain it. I had agreed to drive my shooting buddy up north to obtain a loaner vehicle while his state vehicle was being repaired. John could see I was not impressed with where this conversation was headed, and wisely announced it was time for us to get moving. Instead of heading north for his loaner, we spent the next hour in the local Sportsmans Warehouse, mostly handling various firearms they had on display.

I have nothing but total respect for my co-horts in crime, but it is conversations like this one that leave me more than a bit bewildered, asking myself where my profession is headed too.

But I do totally agree with your comment that folks should choose a round they can shoot well, and shoot it often. While I think it is great our site is able to share valuable information on weapons, ammo and tactics, I think it is also important to remind folks too. A round that functions perfectly in my pistol model x and shoots tight groups - may not function or group well for them in their model x too. That is where the importance of practice with your intended carry round is clear. There is only one way to see if it will function and group accurately, and that is to shoot it.

Just my thoughts for what they are worth.

twoguns
 
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as your moderator I'm not supposed to "butt in&quot
Gee whiz. When I was a moderator on www.fnhipower.com I never hesistated to "butt in" if I thought I had something significant to contribute.
(And for me, that was pretty frequently. ;))


I think that there's a natural tendency to become obsessed with ammo performance and stopping power because, although really not very important, it is a variable in a gunfight that we have complete control over: We can choose the ammo that we feel is the most effective.
 
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One other thought, that has not come up, is that some ammo makers use "test" barrels to obtain their fired results while others use real guns. In some cases, that will produce very real differences in the result. As for me, I carry gold dots, 115gr, loaded to +P+ in my Hi-Power but use reloads for practice. I put about 50 rounds a month of the +P+ ammo through the Hi-Power and about 500 rounds of reloads. I have not seen any signs of excessive wear on the gun.
 

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You've all guessed my pun about butting in. Yes, I enjoy butting in on an interesting thread like this where the discussions are cool and considerate. Keep up the good attitudes on this forum.

However, something wrong with my Websters Dictionary, I can't find Josh's word, " facitious".
What does that mean, Josh? Or what dictionary is it in? You've got to remember that oldgranpa is not smart like a Gieco caveman.


og....who sometimes makes a butt of himself by butting in ::)

Oh, p.s., SAAMI pressures are at the top of this forum in a sticky.
 

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Hello OG,

The connotation of the word is somewhat along the lines of the expression "tongue in cheek".

You certainly hit the nail on the head about there not being data via SAMMI about +p+ ammunition. I suspect that it is an invention for LEA's that require their officers to use .38 special ammunition instead of .357 Magnum ammunition back in the wheelgun days of law enforcement.

Them were the good ole days for sure!

Chris
 

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S&W built a .38 Special for the CHP that was +P+ rated and designated the Model 68.

One other consideration is that although there are no SAAMI specs for +P+, the ammo was originally produced for large agencies who could specify pressures and other characteristics, as well as control its use and distribution.

Regards,

Pat
 

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thanks to Chris and pff for your comments. I really does seem that +p+ was an invention for sales to agencies that buy ammo in large lots. Otherwise, us civilians would probably not support it, just my opinion, and the left overs ended up in gun shops.
For that reason, and another one...the mythical "one-shot-stop" (OSS)... I won't waste my money on +p+ ammo, again, my opinion.

An excellent article by Stephen...
http://www.hipowersandhandguns.com/Have%20No%20Faith.htm
shows again the false hope of a guaranteed OSS from a handgun.
If I really want such a OSS, then I'll use a highpower rifle. Or some might choose a shotgun with buckshot, etc. When I consider the results from some of my wetpack tests, the "distruption" produced by a handgun bullet just can't compare with a rifle round.
Here is an old picture showing typical distruption with a rifle round, I think this was with just a simple 30/30....
http://i3.photobucket.com/albums/y63/oldgranpa/Reloaded30-30wetpack.jpg
(picture too big to post directly)
about the closest thing to this I've seen with a handgun is with a good 230grain .45acp JHP round. I'm sure .50caliber would be close, but few carry a 50 that I know of.
So again, those are just my opinions. Use +p+ if you want to but better be really good with your "placement" if you want a OSS ::)

Finally, thanks Chris for the definition of Josh's word. I still can't find it in any dictionary I have or even in my wife's "Franklin" digital contraption. The closest word I can find that might be appropriate is "fatuous" meaning stupid, or silly, which seems to fit me better


og
 

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that is the correct spelling, Pat, thanks. (I was hoping Josh would admit his spelling mistake when I remarked his word wasn't in the dictionary.) Anyway, fun with words on this thread too!!

Also, just remember something else about SAAMI v.s. +p, etc. and that is velocity doesn't always mean higher chamber pressure. Higher chamber pressure will increase velocity for the same ammo in the same handgun but, and this is a big but, just because a round has high velocity doesn't necessarily mean it's +p+ or even just +p. An example is the CorBon DPX round which is not rated as +p but has higher velocity than many +p rounds in the same caliber. This is due to the light weight copper bullet in DPX. Another example I can think of is the RBCD round which has a light weight lead bullet backed by a plastic wad (sort of a reverse Pow'rBall that CorBon makes). The RBCD has extra high velocity, much like a miniature shotgun shell with the plastic wad pushing the bullet out the barrel.

So at the risk of violating my own rules and starting a little caliber war, I'll just leave it at that.
The whole subject is so complicated we'd need a factory ammo expert to explain it all to us.

Cheers, and as Stephen writes...practice, practice, practice.

og....I'm done now!
 

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+1 on to OG's wish of having a factory ammo expert spill his guts...er explain the interrelationships of pressure, velocity, and gun function bullet design.

Clearly there are energy floors and ceilings that a round has to stay within to make sure the majority of semi-auto pistols operate reliably. There must also be a similar envelope that a rounds energy/velocity must stay within to ensure reliable expansion of a hollowpoint within a given medium. I would be very interested in what those envelopes are for given bullets. I am sure that is "secret stuff" for ammo companies.

To the extent that I can do a paper/internet "analysis" I have decided Speer's GDHPs, in both standard and +P configuration, for my 9mm and .40 Hi Powers are desirable, as well as the Winchester Ranger T 127 +P+. The GDHPs and the Rangers seem to have good "street results," and they function reliably in my Hi Powers. I believe there is at least one company that takes GDHPs and loads them to higher velocities, and I have always wondered if this really improves the terminal performance, or if there is a point where you can push the bullet so fast that you lose reliable expansion - maybe it comes apart, or doesn't expand properly or something. ??

I recently got a good deal, I think, on the 9mm 127 +p+ Winchester Ranger Ts and bought 500 of them. I plan to function check this batch, and check the velocities, and may even wetpack them just for fun. I will be interested to see if the +p+ actually results in higher velocity out of my guns or not.

T'was an interesting discussion.

elb
 
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