+p or +p+ 9mm load data

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black_hog_down

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CAUTION: The following thread may include loading data beyond or not covered by currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.


I would like to work up a hot 9mm load for a 9mm AR15.
How do I find load data for this? Does it exist?
I think I should be able to load an AR pretty hot.
Anybody have any experience loading +p or +p+ 9mm?
The answer to why is hunting hogs in a place that allows pistol ammo only.
 
Western powders has 9mm +P data. Alliant might have some, check their website.

+P+ is off the scale so no official data.

Most ARs are blowback, so it remains to be seen how hot they can be loaded.
 
SAAMI does not recognize a +P+ standard for any cartridge. When loading above published +P charges, you are in uncharted waters and do so at your own risk.

And keep in mind that firing rounds generating more pressure than the chamber/cylinder is designed to handle can cause damage that is cumulative so that everything seems to go right for the first round and maybe even the fiftieth, but at round 250 you get a catastrophic failure. Be very careful.
 
I feel the real answer to your issue isn't more power but a better designed bullet. One that is better suited for your intended application.

If I was hunting with a 9mm I would definitely try a cast bullet with a decent meplat on the end. Perhaps one designed like the lee 125 gr rnfp. I know this bullet is designed for a 38/357 but it is widely known to work outstandingly in a simi-auto 9mm as well, you just have to size it to .356.

An acquaintance that hunts the neighboring property took a doe last season with his 9mm high point using that exact bullet. I was hunting close to him ( though neither of us knew it at the time) so I offered to help with the drag. The bullet made a complete pass through leaving a generous blood trail. I watched as he field dressed the deer and was quite impressed by the wound channel that was created by this little bullet. According to him the shot was taken at about 70 yards and the deer was down within 50.

I would find it hard to believe that any available HP would do a better job regardless of how dangerous you load a 9mm.
 
I mentioned that +P+ loads may be above SAAMI limits, only because I'm aware of one commercial +P+ load that actually runs lower pressure than their +P offering in .38 Special.

Black Hog Down,

If you are going to play with high pressures much, you may want to think about pressure measuring. This instrument works fairly well for me.
 
Been poking around with this same idea, in an AR and all. Haven't had any luck finding a good load. That said for what you want to do with it I think Riverratt gives the best advice, tge right bullet will make or break this equation. And as fast a one could put several rounds into a hog with an AR it sounds like a great platform to use.
 
SAAMI specs:

9mm up to 35,000

9mm +p up to 38,500

No such thing as SAAMI +p+ so your looking at numbers from 38,501 all the way to kaboom.

I have made som pretty "hot" 9mm loads in the for of 9mm major loads for gun games but I don't run them in my 9mm carbines. That said with the longer barrels, you can get decent results with "normal" loads.

When I was younger I used to work up 357 loads near 41 magnum levels, now that I am older I'd rather down load a 44 magnum to 41 mag levels. Everything lasts longer if your not pushing the limits.

That said the largest animal I have killed with a 9mm carbine is a coyote. I have lots better uppers for hogs.
 
Chainsaw. said:
Been poking around with this same idea, in an AR and all. Haven't had any luck finding a good load. That said for what you want to do with it I think Riverratt gives the best advice, tge right bullet will make or break this equation. And as fast a one could put several rounds into a hog with an AR it sounds like a great platform to use.
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I have starting doing research on 9mm "major" loads. Looks like there is plenty of load data for this and I will start low and work up to max levels.
Am I wrong to think that an AR platform with a heavy buffer is perfect for hot loads? I have seen some posts about the bolt catch breaking after many rounds of +p but not much else.
 
Well I think of "Uzi only" loads. Given the bulk of the chamber on a 9mm AR Id have a hard time believing it couldn't hold up.
The bolt catch is an issue namely due to how much mass it takes to slow a bolt and BIG buffer, mine doesnt catch on the last round so....meh.
 
Am I wrong to think that an AR platform with a heavy buffer is perfect for hot loads?
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What's "heavy" to you?

As I said above I don't run 9mm major loads in mine, standard 9mm bolt carrier and buffer.
 
When I was younger I used to work up 357 loads near 41 magnum levels, now that I am older I'd rather down load a 44 magnum to 41 mag levels. Everything lasts longer if your not pushing the limits.
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^^ I could have written that. ^^

Just this week I completed a workup for 124gn 9mm, using Power Pistol. I got up to 1245 f/s (5" bbl) while staying within published data. I settled on the charge weight that delivered 1210 f/s, and seemed like plenty of punch to me. And those are only for defense level. The "range ammo" version is with 0.4 grains less; because I don't like tearing up my guns.

Point is, 9mm can be a pretty good performer within published data, IMO.
 
That 1300fps looks like a good target. Gonna try to start at official Max and slowly work my way up to 1300 using a chronograph.
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That's not how it works, you are asking for trouble IMO.

You want "off the charts" ammo and don't want to put in the time investment into it either.

"Max" is short for Maximum, that's where load books tell you to stop not start.

If you just want 1300 fps, go get a box of Hornady #35500 bullets and load them with 5.4gn of AA#2 @1.080" OAL, you should get over 1300 fps from a 9" barrel and still be well under the max charge of 6.1 grains.
 
+P+ has no SAAMI standard, but you can buy commercial loads with that label. In the end it signifies "not to SAAMI pressure standard". It seems to me the OP is wanting to go there, which is why I added the warning to the top of his post.
 
B_H_D, in years past, I loaded a lot of 9MM with a Herco load that was listed in the Speer #8, and possibly other reloading manuals of the day. I used jacketed 125 grain and 115 grain bullets with 7 grains of Herco for approx. 1300-1400 FPS in pistols, depending on barrel length. I chronographed the 115 grain in a 16" carbine barrel and it averaged 1502 FPS. FWIW, Winchester and Federal 9MM +P+ averaged 1300-1400 Fps in pistol barrels, depending on length, and 1580+ FPS in a 16" carbine. BTW, recently tested a few rounds of some old, 1993 dated, CorBon 115 grain 9MM +P. Averaged 1440 FPS in a 5" barrel, and 1665 FPS in a 16" barrel. Flattened primers, and one pierced primer, occurred with this ammo in the carbine.

The handloads mentioned caused no issues in any of my guns, but I suspect they might be considered +P or +P+ today's litigious society.
 
I pushed the limits with a Browning HP back in the early 80's. I didn't have a kapow but I turned a good gun into a POS in 4000 rounds.

I was young and stupid.
 
The upper and lower are the same as for 223. The barrel is not going to blow with a little extra pressure. The chamber is fully supported so the brass will not blow.
I think the weak links are the primer and the bolt.
9mm pressure is ~32k and 223 pressure is ~53k.

So... I think that the AR is a good platform to push the limit of the 9mm envelope. I can watch for pressure signs and if a part wears out sooner then I can replace it.

I wouldn't feed it a steady diet of hot rounds just when I'm hunting.
 
The upper and lower are the same as for 223. The barrel is not going to blow with a little extra pressure. The chamber is fully supported so the brass will not blow.
I think the weak links are the primer and the bolt.
9mm pressure is ~32k and 223 pressure is ~53k.

So... I think that the AR is a good platform to push the limit of the 9mm envelope. I can watch for pressure signs and if a part wears out sooner then I can replace it.
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Writing things like that won't help your cause and make folks think your doing something that's a good idea.

Comparing a straight blow back recoil operated 9mm to a gas operated locking bolt .223 is like saying I don't mind being hit in the head with a pillow so a hammer shouldn't hurt. They are not the same thing.

I'll help you though, if you promise to post photos if you hurt something or yourself. 10.0 grains of HS-7 will push a 115gn JHP, using a Winchester small rifle primer 1450 fps out of a 5.5" barrel.
 
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Hodgdon HS-7 aka Winchester 571, are both obsolete. The newer 572 looks to be fairly close in burn rate, but won't be an exact substitute. All I can say is that both 571 and 572 are positions slightly slower than Vihtavuori 3N38. Hodgdon lists 572 as sightly faster than Blue Dot, and no longer lists 571, while Western's burn rate chart puts 571 slower than Blue Dot, but it also puts 3N38 slower than Blue Dot. As usual, burn rate charts have a good bit of wiggle room in them.
 
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