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Discussion Starter #1
Hey guys. On this Forum someone said that you can't use

+P+ loads in your M&P. I'm starting to load for the 9MM

full size. How do I know whether I'm loading a +P load

or a safe in the S&W load? I'm currently using 5 grains

of Bullseye with a 115 grain Speer jacketed H.P.



Thanks,

Zeke
 

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Buy a good reloading manual and read it like you know you should read the Bible! Stay within the printed parameters to be safe.
 

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Discussion Starter #3
Thanks Coltman,



I think I have the first re-loading manual

ever written and lots of them in between. I am probably

suffering from advanced senility but, I just don't remember

seeing anything that says a load is a +P+. In fact I don't

even know the difference between +P and +P+. I have been

at this game for a long time yet, I sure as hell don't know

everything.



Zeke
 

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If I recall correctly....



There are SAAMI specs for +P loads, but there are no established specicications for +P+. Since there are no definitive guidelines per SAAMI, most if not all manufactures won't warrant their products for +P+.



It makes sense when you think about it; if there are no specs then there's only common sense to keep someone from making a 50% overpressure round and labeling it as +P+. It would do a quick and dirty extreme makeover on the firearm and whoever was holding it though.
 

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I am pretty sure that Fallschirmjäger is correct his explanation of +p and +p+ loads. That is how I remember it as well.
 

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Your first problem is that you shouldn't be trying to load hot ammo with Bullseye, it's a recipe for disaster. Bullseye is a very fast powder intended for light loads, mostly for target use, and since it is such a fast powder it doesn't take much to accidentally come up with a load that could possibly destroy the pistol and cause personal injury.



Alliant is the manufacturer of your powder, and they don't recommend Bullseye for a load with a 115 gr JHP, they recommend you start at about 4.6 gr of American Select and a max charge of 5.2 gr of American Select with that bullet, ALWAYS start low and work up! NEVER exceed the maximum loads listed.



http://www.alliantpowder.com/reloaders/Rec...mp;bulletid=358



My personal 9mm load is 4.6 gr of WW231 behind a 115 gr JHP, out of my Beretta Model 92 it averages 1090 fps, which isn't bad.



Another good load that I have used is 5.2 gr of Unique behind a 115 gr JHP, it runs 1154 fps out of my Beretta.



Both of those loads are out of mixed brass and using Federal small pistol primers.
 

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Ok, here's the magic.



Go to google and searche for SAAMI max pressure for whatever cartridge you are interested in loading for.



This page is decent and has a lot of them in PSI.



http://www.lasc.us/SAAMIMaxPressure.htm



Then check the manufacturer load data for the powder you are using in the cartridge you are laoding. They will list a pressure for their max load. Verify this pressure is in PSI. If not revisit google and CUP into the search terms as that is the other unit of measure for cartridge pressure.



9mm luger is 35,000 psi

+P is 38,500 psi.



Often to load +P you need +P brass, which has a thicker web to the cartridge, and thus different internal pressure curves, and different reloading data. Fortunately for 9mm, this is not the case.



Then you should hit up forums and ask around about how the powder behaves with temperature changes, or invest in some internal ballistics software which can make a decent guess at such as well as pressure curves with increasing charge. Some powders spike badly past a certain point.



Then you get a decent powder drop and a reliable scale, and a chrono in addition to the other basics for reloading.



Then you start with a reduced charge and work up very slowly and inspect fired cases keeping a very close eye pressure signs.



As far as bullseye being appropriate? It has load data for 115gr FMJ but not hollow point. It doesn't mean you can't use it for a JHP, as two JHP bullet profiles are likely not the same anyway. However, That fact is one of the reason most load data doesn't go to the ragged edge on pressure. Most powder drops will thow a charge off by .1 grain often enough you ahve to pad for that, and some bullts take up more case space than others, so they have to allow for that too. That's why whenever I get some different bullets in for reloading, I keep track of their dimensions for fufture reference.



Bullseye's max load for a 115gr FMJ is only 31,000 PSI, I suspect that means it gets non-linear at higher pressures and should be used with cuation. Fast powders ina small cartidge tend to be unforgiving.



Working up your own high pressure loads is NOT for people who aren't very experienced at reloading and who have a gun they don't mind blowing up.
 

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Discussion Starter #8
Thanks for the input guys. I got the 5 grains of Bullseye

straight out of the reloading manual. I didn't invent it.

Sounds like from the input I'm getting from you guys

you don't like it and think I should switch powders. I

have no problem with that. I have been re-loading for

many years, but have had no experience with the 9MM.



Zeke
 

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What exactly would a round with a 124 JHP with 8 grains of accurate 5 behind it be at for a psi....I have been looking for a table to calculate things like this, any links.
 

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koumiss45 said:
What exactly would a round with a 124 JHP with 8 grains of accurate 5 behind it be at for a psi....I have been looking for a table to calculate things like this, any links.


Let me just say this... there is NO reliable way to calculate pressure within a chamber. Why? Because, none are the same. It is a completely unique calculation based on the gun. So only go with what you know... it can be very dangerous to just do a calculation and hope you're right. Also, because of the way gas works, the peak pressure is almost 100% subjective and follows no given path. Example: the equation for gas in IDEAL condition, is PV=nRT... p = pressure, v = volume, n = moles of gas, r = ideal gas constant, and t = temperature. Only one problem: the volume of the gun changes with time, and the gas is produced at an unknown rate... so the v, n, and t are unkwown because it can be @ any point in the bullets progression.



Hope that clears some of it up for ya...
 

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ZB338 said:
Thanks for the input guys. I got the 5 grains of Bullseye

straight out of the reloading manual. I didn't invent it.

Sounds like from the input I'm getting from you guys

you don't like it and think I should switch powders. I

have no problem with that. I have been re-loading for

many years, but have had no experience with the 9MM.



Zeke


Bullseye is a perfectly good powder. I just don't know that I'd use it in 9mm. alliant only provides one load for it, 5.0 grains, and it has some headroom for max pressure, but doesn't list if it is a max load or starter load. SOme places list 5.0 grains as both the max and starter load. Which is not the case for say 124gr 9mm.



Given how fast it is, and lack of information, I wouldn't use it for anything other than relatively light loads.
 
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