+P Ammo reloads

JettaRed · Apr 15, 2014

Some load charts show a starting weight for powder and a max. Is the max equal to +P or is +P more than the max weight?

Edit: To be clear (and as some have guessed) I am trying to avoid excessive loads. I just want to make sure the if I am at the max load (and not more) that I have a margin of safety if my pistol is rated for +P.

Traveler · Apr 15, 2014

You have to be very careful with +P. Some powders don't get to +P without dangerous spiking. Look for loads specifically stated as +P. Use +P brass as well.

Example:

http://www.alliantpowder.com/reloaders/recipedetail.aspx?gtypeid=1&weight=125&shellid=27&bulletid=28

BlackBart · Apr 15, 2014

Another reason to use something unbreakable like a Blackhawk or Redhawk.

JettaRed · Apr 15, 2014

So, for example, Alliant Powder states that the max load of Bullseye for 124 gr Speer GDHP 9mm is 4.4 gr. The intro page says to start with 10% less (which equals 3.96 gr). It doesn't give case pressures, but does say not to exceed max.

Not that you know, but does that mean 3.96 gr (4.0 gr) is normal load and 4.4 gr would be +P?

coopermania · Apr 15, 2014

BlackBart said:
Another reason to use something unbreakable like a Blackhawk or Redhawk.

Blackhawks are not unbreakable, Trust me I know, Happened in the early eightys.

Ever see the Blownup Blackhawk 44 in a few of the RCBS Readloading Manuals ??? It was mine.
A short charge of 2400. Blew the cylinder in half, Frame broke under the rear sight. Frame split where barrel screws in. It is in a case in a friends gun store in Anderson Indiana.
Ammo was loaded on a semi progressive Dillon 450.

coopermania · Apr 15, 2014

JettaRed said:
Some load charts show a starting weight for powder and a max. Is the max equal to +P or is +P more than the max weight?

You gotta be careful when working at the upper levels of saami pressure rating.
Learn the signs of excessive pressure and pay attenion too them.

Work up your loads carefully and slowly. Work with powders from the middle of your charts.
With using the fastest and the slowest burning powder crazy pressures can happen fast.
Even more so with small case size ammunition.
Using fast burning powders adding a half of a grain to a small case pressures can go through the roof.
Just the reverse with slow burning powder, To little powder and pressures can go through the roof.
Some factory loaded ammo uses blended powders and you will never get the same results at home.

You gotta crawl before you can walk.

BlackBart · Apr 15, 2014

coopermania said:
Blackhawks are not unbreakable, Trust me I know, Happened in the early eightys.

Ever see the Blownup Blackhawk 44 in a few of the RCBS Readloading Manuals ??? It was mine.
A short charge of 2400. Blew the cylinder in half, Frame broke under the rear sight. Frame split where barrel screws in. It is in a case in a friends gun store in Anderson Indiana.
Ammo was loaded on a semi progressive Dillon 450.

Nope, never seen it. People are unaware a short charge can build pressure as bad as an overload. Is there a link to the pic anywhere now that you have me curious?

coopermania · Apr 15, 2014

I will look around and see if I can find one. If not in the next few weeks Iwill stop in and see my friend. And take a pic. People have been telling me to send it back to Ruger again. I sent it back iwhen it happened because I thought it was Rugers fault. I sent it back with 2 rounds still in the cylinder, The pin was bent and I could not spin the cylinder. They instantly told me no warranty because of a overcharge. I wrote them back and said pull the bullets and see for yourself. It was supposed to be a compressed load of 2400 and a cast keith bullet. After the bullets were pulled they offered me a new pistol for 121.00 and I turned it down. For a few years I thought is was Rugers fault, It was the first shot of the day. Years later I picked up P O Ackleys Vol 1 & Vol 2 and read and learned a lot. It was a short charge of slow burning powder. And I ended up with rifle pressures in a revolver. I have been told that Ruger handles blowups different now days.. I don't know. I get you a pic as soon as I can. With the Dillon 450 it has a manual primer and powder measure. I must not have pushed the measure handle all the way in on one round in a box of fifty. And that round was. The first round I fired from that box.. what are the odds of that.LOL

Silverlode · Apr 15, 2014

Not sure if anyone actually answered your question. No, +P is not max load. It is in excess of that and will produce pressures greater than max saami.

coopermania · Apr 15, 2014

BlackBart said:
Nope, never seen it. People are unaware a short charge can build pressure as bad as an overload. Is there a link to the pic anywhere now that you have me curious?

I will look for a pic but I would not have a link.. this happened around 1981- 82

Uncle Duke · Apr 15, 2014

JettaRed said:
So, for example, Alliant Powder states that the max load of Bullseye for 124 gr Speer GDHP 9mm is 4.4 gr. The intro page says to start with 10% less (which equals 3.96 gr). It doesn't give case pressures, but does say not to exceed max.

Not that you know, but does that mean 3.96 gr (4.0 gr) is normal load and 4.4 gr would be +P?

Speer #14 indicates a starting load of 3.9 grains of Bullseye for the 124 grain GDHP, with 4.4 grains being the do not exceed maximum charge. Start at 3.9 grains and work up VERY carefully from there.

My original thought when I saw the title of your post was that you were referring to 38 Special. There is of course factory made 9mm Luger +P ammunition as well. As mentioned by Coopermania, some factory loads are achieved with powder blends that are unavailable to hand loaders. In 9mm Luger you are dealing with a cartridge that, especially when compared to 38 Special, is loaded to much higher pressure to begin with. Be Especially careful to follow and continually monitor seating depth specs with 9mm, and especially as you approach maximum loads. Very small differences in seating depth can dramatically effect pressures in this cartridge in particular.

730dc · Apr 15, 2014

max load is not a +p load in less it is stated as it is . only place i have seen published +P data is on ramshot powders online data ... never seen it anywhere else but im relatively new to reloading.

damifinowfish · Apr 15, 2014

Why do you want +P 9mm reloads?

Personally I think your playing with fire reloading +P 9mm

Biggfoot44 · Apr 16, 2014

The Data that Jetta refers to , the *Max* load is maximum to remaon within SAAMI Std pressures.

*General Background*

There are a handfull of established standards for "Plus P" loads. These include (off the top of head ) 9mm , .38Spl , .45acp , and .257 Roberts . Unoffical , but widely recognized industry standards exist for loaded ammo for .38Spl +P+ , and 9mm+P+ . Most suppliers of loading data will have a section of " Ruger and T/C ONLY" for .45Colt , and Marlin level ( formerly known as '86Winchester level) loads for .45-70 .

Meanwhile at the origional subject of this thread , I'm not sure if Jetta is trying to find +P loads , or avoid them.

Inherently 9mm is not a very forgiving ctg to load. It is a high pressure ctg , with a small powder capacity. Small changes in charge weight , seating depth , or even differenced in case capacity and neck thickness between different brands and lots of cases can make a big difference in pressure.

Also if you search out the small amount of pressure tested 9mm +P data , you will see that it often involves different powders than std vel , not simply increased charges.

Handloaders may well not be able to duplicate factory loads in 9mm +P and +P+ , because OEM Mfgs have access to custom blended powders , not available to handloaders.

In short , if you have to ask about loading +P 9mm , you probably shouldn't go there. For moderate ammounts of hot loaded 9mm ammo for SD or hunting , just buy a cpl boxes.

byf43 · Apr 16, 2014

BlackBart said:
Another reason to use something unbreakable like a Blackhawk or Redhawk.

Guaranteed...... Ruger Blackhawk WILL come apart.

There was a guy at my sportsman's club, that brought his Blackhawk (in .357) to a meeting, and it was in peices.

He was using Unique, and didn't pay attention to loading data.

Cylinder was in multiple pieces.
Topstrap was broken off the frame.
He was using some Speer 160 gr. half-jacket softpoints.

Blackhawks are strong, but, they aren't indestructible.
With enough stupidity, anything will come apart.

alucard0822 · Apr 16, 2014

As others have said, +p is a different, higher pressure SAAMI specification. When reloading, the load data was most likely developed in a test barrel under ideal conditions, you reduce by 10% and work up in order to account for variables, tighter barrel, more friction in that particular bullet, temperature, exact case volume, minor differences for that lot of powder, or the available volume for your brand of brass, even variables in the primer. You might duplicate the data grain for grain, find the max load is accurate, no pressure signs, and velocity matches, or is a bit under the test data, that is an ideal circumstance that doesn't always happen.

You can often find, especially in small volume/high pressure calibers you may be at the published velocity with a reduced load, you can infer you are probably at the published pressure too, so even going to max may actually exceed the data. There are many that hotrod cartidges using their best guess without load data to go by, I don't, but I will work up plenty of +p loads, and some that are recognized with established load data, but are above SAMMI spec, like 9mm major, full power magnum revolver rounds, 38 super, 10mm(especially long OAL revolver loads) 45 super 45colt, and 460 Rowland. It can be it's own fun to develop and shoot a hot load that is safe in a certain model, or modified handguns, long as you have the experience and data to keep you safe and out of trouble. Never forget reloading is like a math test, where a wrong answer can blow off your hand.

JettaRed · Apr 16, 2014

To be clear (and as some have guessed) I am trying to avoid excessive loads. I just want to make sure the if I am at the max load (and not more) that I have a margin of safety if my pistol is rated for +P.

Sent from my iPhone using Tapatalk

coopermania · Apr 16, 2014

Excessive pressure loads generally start with hard extraction depending on firearm being used and primers that are starting to flatten out. The next level of pressure will be flat primers or blown out primers and the headstamp on the brass will start flowing.
Generally when you see primers that start to flatten out ( the curves around the primers edges flatten out towards the sides of the primer pocket ) you have reached your pressure limit with that powder.

Magnumite · Apr 19, 2014

And don't forget the primer gas leaks which leave burn holes on the breech face. While this could be caused by a loose primer pocket or excessive headspace, it is also a sign of excessive pressure in high pressure cartridges.

As others have indicated some powders are not forgiving when getting into higher pressure. Blue Dot is one of those powders. Wonderful in its working pressure range. But it gets hairy if you push it too much. There are better powders for that type of loading.

+P Ammo reloads

The #1 community for Gun Owners of the Northeast

Member Benefits:

Ultimate Member

Lighten up Francis

Banned

Ultimate Member

Banned

Banned

Banned

Banned

Ultimate Member

Banned

Ultimate Member

Active Member

Ultimate Member

Ultimate Member

SCSC Life/NRA Patron Life

For great Justice

Ultimate Member

Banned

Ultimate Member

Users who are viewing this thread

Log in

Forum statistics