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+p +p+

Discussion in 'Reloading' started by kd8x, Jul 23, 2012.

  1. kd8x


    Dec 24, 2011
    Noob question here...Reading new Lyman manual and it has powder loading levels minimums and maximums....I understand all that....So what about loading +P or +P+ handgun loads. Lyman manual doesn't tell me anything about that...Little education here is well appreciated....:whistling:
  2. janice6

    janice6 Silver Member

    Apr 4, 2006
    I understand there is no specifications for a "Plus, or Plus P Plus, load. Therefore, no one would legally suggest a load.

    But I am not a re-loader, just a reader.

  3. Angry Fist

    Angry Fist Dehumanizer® Lifetime Member

    Dec 30, 2009
    Hellbilly Hill
    What's a proof load come in as?
  4. dkf


    Aug 6, 2010
    SAAMI does not recognize +P+ ammo. Some cartridges have no SAAMI specified +P. The ammo companies have made up some of their own +P or +P+ designations that SAAMI never recognized. Basically both mean a hot load with fairly high pressures. Some pressures exceed the specified max but do not exceed the proof pressure.

    Some reading
    Last edited: Jul 23, 2012
  5. fredj338


    Dec 22, 2004
    For liabilty reasons, no one is going to print over pressure loads & if you find them on the internet, be very, very careful about using such data. Powders burn at non linear rates once they reach max & what you may assume is just slightly over, could pressure spike & cause a KB. So best to leave the +P or +P+ loading to the very experienced reloaders that have some equip & the knowledge to interpret the data & pressure signs.
    Last edited: Jul 23, 2012
  6. TX Archer

    TX Archer

    Jun 4, 2011
    Austin, TX
    My comment is coming from someone who is coming up on a year of reloading so I'm far from a veteran. I've learned a lot from the folks here, on other boards, and from reading my manuals. Among the most important things I've learned is where not to venture. You stated that you're a "noob" so I'd take Fred's advice and stay away from there.

    If you're trying to simulate your defensive ammo for practice purposes, there are loads that will approximate the feel while still staying within published data.
  7. michael e

    michael e

    Nov 20, 2010
    I know I have a book listing 38+P but think that is the only one that is listed in any of my data. Not sure what book it is in since I have 5-6 books and a few more print outs from powder companys.
  8. WeeWilly


    Nov 12, 2011
    There are some recognized SAAMI +P loads, for instance 9mm,.38spl, .38Super, .45ACP. I think +P is confined to 10% over maximum SAAMI pressure for the standard caliber. I don't think SAAMI recognizes +P+, so it is a manufacturer designation for something greater than 10% over basic SAAMI maximum pressures.

    As Fred explained, stay within published load guidenlines, work up to published maximums using safe loading techniques and you are assured a fun and safe hobby.
  9. WiskyT

    WiskyT Malcontent

    Jun 12, 2002
    North Carolina
    This. It is generally not hard to duplicate factory ammo velocity, including +P ammo, with standard pressure loads from legitimate data sources.
  10. bush pilot

    bush pilot

    Jan 29, 2004
    ++++++P loads? Where's Clark? Someone should head over to The High Road and tell him he's needed over here.
  11. c01

    c01 Crazy Eye

    Feb 18, 2010
    True. Lol!
  12. fredj338


    Dec 22, 2004
    The problem is w/o pressure gear, you are guessing. The max book load can be right @ SAAMI max pressure & going as little as 0.2gr over w/ some powders can result in a pressure spike (ie, Clays). It's why no responsible outfit posts +P load data for anything but 38sp or hvy 45colt loads for Ruger's. Those cases are really large compared to 9mm or 40, so pressures will increase diff there.
    Last edited: Jul 24, 2012
  13. WeeWilly


    Nov 12, 2011
    For the calibers where a +P designation is recognized, like 38spl, 38Super, 9mm, 45ACP, all that needs to be done is for someone with pressure testing capability is for them to develop the load.

    For instance, Hodgdon publishes load data for 38spl +P and 38 Super +P, because they developed loads that they know don't develop more than what SAAMI says is +P (roughly 10%+).

    I am not advocating anyone develop their own +P load by adding powder over max for the standard caliber, as you say, that would be shooting in the dark, not knowing where on the knee of the pressure curve you were...
  14. fredj338


    Dec 22, 2004
    Sure, company's could certainly work up & publish +P data, but the liability is huge. There is always some guy that knows better & figures he can go just a bit over listed data & be safe & bang, KB. As we knowm few in our soicety take responsibilty for their own actions so someone is getting sued.
    As noted, you can get +P like vel out of most calibers by using book data &/or slower powders & do it safely. With a chorno & good understanding of pressure signs, you can get there, but why? Really, for the sake of 50fps extra vel, why? You can easily get to within 30fps of any +P or +P+ load manuf today w/ book data. You will not know the diff in your shooting.
    Last edited: Jul 24, 2012
  15. shotgunred

    shotgunred local trouble maker

    Mar 1, 2008
    Washington (the state)
    If you need a +p or ++p load you should simply switch calibers to a more suitable one.

    I suggest you you would be much better off looking at the 357 sig instead of trying to see if you can a little more out of your 9mm before you blow up your gun.
  16. ss30378


    Mar 14, 2012
    Companys have published some higher pressures for rounds that are commonly loaded above factory specs. Ones like the 45 colt and 45-70 have various levels listed for the guns that can handle them. For 9mm (im assuming the round you're asking about) there are 4 levels of pressure standard saami, +p, +p+, and the many 9mm major loads are in the 50k psi range which use rifle primers to help contain the pressure. Equalling factory loads is easy with most powders, also take into consideration that the ammo companies will choose the propellant they use based on cost effectiveness. They have a set max pressure (SAAMI or CIP) and a velocity they want to achieve and will test which powder will get them there with the fewest grains. A powder that will save them a half a grain will add up to a nice $ savings when they make millions of rounds each year. Using some of the more costly powders or the ones that use a bit more like the vihtavuori powders or my favorite Power Pistol can net you higher velocities without raising pressures. For the +p, +p+, and 9mm major loads you wont find them listed in any manual but data is out there, and the guns that shoot them arent stock (in 9mm major anyway) and they start low are very carefully worked up. My 17l can actually make major with barely tapping into +p pressures. Barrel length can help and every gun is different so if you want to push the envelope be careful. Another issue i ran into when getting over the 1500 fps range is bullets dont hold up. So in most cases the extra speed not only isnt worth it, its counter productive.
  17. fredj338


    Dec 22, 2004
    You assume a lot. Most ammo manuf use non canister powders blended for their specific needs. So the fewest grains thing is a bit bogus. They can blend a powder anyway they like. Take apart a Hornady light magnum rifle round, it's packed with slow burning powder to 101% density. FYI, you think your loads are withins SAAMI spec pressures, but unless you are using pressure equip, you are only guessing. Just because you brass or gun doesn't come apart doesn't mean the load is within acceptable pressures. How many loads do yo uget out of your 9mm major loads before the primer pocket stretches? A load that is within spec rpessures will go 10 reloads + before stretching a primer pocket in good brass. If the pocket shows stretching after 1-2 relaods, you are way over even +P pressures.
  18. ss30378


    Mar 14, 2012
    For the light magnums the fed high energy or corbon, bba or doubletap ect.. style loads that youre referring to I agree they are selling velocity to the consumer so they will get powders the avg Joe wont be able to get to get impressive numbers at reasonable pressures. Hornady sells the superperformance now so thats available to the avg person. But those pedal to the metal rounds cost a dollar a piece on up. For the avg plinking rounds, many have been pulled apart to find stardard grade canister powders. Then the cost savings gets applied and they will go for the more for less attitude. The big companies can have anything mixed for them and do when its needed. Standard walmart grade ammo isnt this type of ammo that needs special blends to get wild performance. Its all about cost. We use propellants everyday at work for rockets. We have at our disposal anything we want and the technology to test it in every way shape and form in both simulations and and reality. When it all comes down to it its what can we use to get it dont that costs the least. Thats the only way to get the directors approval. Its business 101. And my "major" brass has 5-6 reloads so far on it and still looks good.
    Last edited: Jul 26, 2012
  19. VN350X10


    Apr 13, 2001
    McHenry, IL
    I usually lose my 9Major brass before it gets loose primer pockets, but in testing I've loaded some cases 15 times & primers are still tight.
    As was said, a longer barrel helps a lot with these loads.

    back to the basic original question, a +P load in a RECOGNISED CALIBER that lists one, is about a 10% above normal pressure load.
    the "+P+" designation is NOT supported by SAAMI.
    These loads came about originally for the Treasury Dept., they were a VELOCITY SPEC loading for 2" snubbies. The brass wasn't even marked .38 Spl on the headstamp, it had the designation "F C xx", the x's being date of mfgr. like a military load. It was a special loading by Federal for LE use only, prior to the introduction of snubbies in .357 mag. So it's by far NOT a new thing.
    The only ammo I've seen marked with a "+P+" on the headstamp is some IL State Police 9mm in my collection, but this was only sold on LE contracts, never avaliable to the public thru legitimate retail outlets. I have examples in my collection of Fed, Rem & Speer, all of which sold ammo to the IL State Police. The range that I used to work at was used by several LE agencies, so I managed to get samples.

    FWIW....I get my 9Major velocities below published max loadings of Vhit. 3N38 powder, from Vhit.'s load data. But I use 147 gr bullets to do so. With a 17L length barrel with an added comp, I'm at almost 7" of barrel length, which works for me, as I tend to shoot smoother with a longer pistol. Like a longer barrel forcing a trap shooter to follow thru.

    Final advice....DON'T try to come up with your own version of a +P+ load, you WILL break something, possibly yourself !

    load safe !

    uncle albert
    Last edited: Jul 29, 2012