The accuracy potential of the 9x19

I've owned a couple of 9mm carbines (older model PC9 and Camp9) for close to 2 decades. We shot them for fun and I used to keep one as a bedside gun. Using 147 grain bullets and red dot sights, those carbines are suitably accurate for home defense use past 100 yards.
I've spent some time shooting the pair of AR9 "pistols" lately and have found them far more accurate than one might expect. Both the 7.5" and 10.5" will consistently smack the 4" swingers @ 50 yards. The 10.5" doesn't much care what weight or velocity load is used but the 7.5" seems to prefer either 115 or 147 at factory velocities.
The 10.5" is a cloverleaf performer with 147 sub-sonic. The 7.5" is a work in progress. Both however, will push the little handgun round into rifle territory w/o much effort.

Thanks for the report. I had thought an AR-9 pistol could make a good home defense option.

"I had thought an AR-9 pistol could make a good home defense option."

Choose your ammo according to your specific circumstances. Keep in mind that the longer barrels add considerable velocity to the specs. The 115 bullets are probably making 200 fps more and the "subsonics" become low end supersonic. I found 147 grain loads that made 950-1000 from 4" barrels were at or above 1150 from the 10.5". The "softer" 147's will really open up with the increased velocity.
My intent is to have a manageable AR based weapon that is both more accurate and more powerful than a 9mm handgun w/o the obnoxious muzzle blast of a .223 or the totally unacceptable over penetration of sub-sonic 300AAC. The 9mm is far easier to suppress than even the 300AAC so I can run a lighter, more compact suppressor.

For defensive loads bonded bullets that are not likely to fragment are also probably a good idea with the increased velocity from the carbine length barrels.

Mike J said:

Thanks for the report. I had thought an AR-9 pistol could make a good home defense option.

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I love mine, SBR without the stamp or hassles. Endomags allow the use of a standard lower and fit your 5.56 pouches.

"Endomags allow the use of a standard lower and fit your 5.56 pouches."

Yes and they do work. I will offer a word of caution regarding the use of endomags. Consider the chamber clearing process commonly used with the AR platform-- drop the magazine and rack the bolt to empty the chamber. Since the ejector is part of the magazine when using endomags, the live cartridge that was in the chamber is held on the boltface by the extractor and rechambered. I replicated this about 10 times and each time the round went right back into the chamber w/o a snag. At this point the user thinks the chamber is empty and the gun is safe because that's the way it's been done previously. Unfortunately, the shooter still holds a gun with a loaded chamber.

Mobuck said:

"Endomags allow the use of a standard lower and fit your 5.56 pouches."

Yes and they do work. I will offer a word of caution regarding the use of endomags. Consider the chamber clearing process commonly used with the AR platform-- drop the magazine and rack the bolt to empty the chamber. Since the ejector is part of the magazine when using endomags, the live cartridge that was in the chamber is held on the boltface by the extractor and rechambered. I replicated this about 10 times and each time the round went right back into the chamber w/o a snag. At this point the user thinks the chamber is empty and the gun is safe because that's the way it's been done previously. Unfortunately, the shooter still holds a gun with a loaded chamber.

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Just a slightly different procedure. If you don't shoot it empty, pull back on the CH while holding the bolt catch, then drop the mag.

I'll have to disagree.. seems to me the .223 / 5.56 round was designed to make nice clean holes and go through and potentially hit someone else and do minimum damage (part of the forgotten rules of war) I know in reality it usually does not do this as well as initially designed but still.. For defense I'd personally rather have a larger diameter round and one that expands instead of fragments and is less likely to go through walls.

blume357 said:

I'll have to disagree.. seems to me the .223 / 5.56 round was designed to make nice clean holes and go through and potentially hit someone else and do minimum damage (part of the forgotten rules of war) I know in reality it usually does not do this as well as initially designed but still.. For defense I'd personally rather have a larger diameter round and one that expands instead of fragments and is less likely to go through walls.

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Disagree with whom?

home defense use past 100 yards

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Man, you must have a big ass house :wink:

s4s4u said:

blume357 said:

I'll have to disagree.. seems to me the .223 / 5.56 round was designed to make nice clean holes and go through and potentially hit someone else and do minimum damage (part of the forgotten rules of war) I know in reality it usually does not do this as well as initially designed but still.. For defense I'd personally rather have a larger diameter round and one that expands instead of fragments and is less likely to go through walls.

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Disagree with whom?

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Basically that an AR pistol would make a 'better' home defense gun than a standard pistol with standard pistol ammo. Any gun is better than no gun... but still there are better guns for certain situations....

"Man, you must have a big ass house"
I probably used the wrong words on that. Let's modify that to "personal defense at home". My "home" can legally be construed as the property I own on which I have the absolute right to stand my ground. Not all defense scenarios are going to be inside the house for me. It is more than 100 yards from one side of my yard to the other.

"Basically that an AR pistol would make a 'better' home defense gun than a standard pistol with standard pistol ammo."
I'm not arguing that point. It seems that the AR platform is going LEGO on a huge scale with many versions going way off into the weeds. Some users are just more "comfortable" with an AR type firearm than with a typical handgun. The ammo is the same whether the gun is a 3" barrel midget or a 10.5" AR pistol.
My primary goal on this project was to construct a "Personal Defense Weapon" (PDW) using a cartridge that I already have on hand in a more effective package--more accurate beyond 15-25 yards, a bit more power for outside use, and easily & efficiently suppressed for inside use.
The out take of the testing was a re-affirmation of the accuracy of what many consider a short range round when fired in a longer range capable platform.

I suppose you are right in a way but you know what hangs beside my door to the outside?

The original Ruger Police Carbine in 9mm.

Got one of those and a P89 in my work vehicle too.

blume357 said:

s4s4u said:

blume357 said:

I'll have to disagree.. seems to me the .223 / 5.56 round was designed to make nice clean holes and go through and potentially hit someone else and do minimum damage (part of the forgotten rules of war) I know in reality it usually does not do this as well as initially designed but still.. For defense I'd personally rather have a larger diameter round and one that expands instead of fragments and is less likely to go through walls.

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Disagree with whom?

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Basically that an AR pistol would make a 'better' home defense gun than a standard pistol with standard pistol ammo. Any gun is better than no gun... but still there are better guns for certain situations....

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AR "pistol" in 9mm, as pictured, best of both worlds :wink:

My "home" can legally be construed as the property I own on which I have the absolute right to stand my ground. Not all defense scenarios are going to be inside the house for me. It is more than 100 yards from one side of my yard to the other.

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While I agree completely, you might have a time claiming self defense if the "target" is 100 yards away. Just playing devil's advocate.

blume357 said:

I'll have to disagree.. seems to me the .223 / 5.56 round was designed to make nice clean holes and go through and potentially hit someone else and do minimum damage (part of the forgotten rules of war)

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It was designed to wound not kill. Causing the enemy to expend time and men to care for the wounded. It was also designed and does tumble creating a larger wound channel.

As usual I 'sped red' and only saw AR and not AR-9.... for a long time I wanted a AR in 9mm still on my list but a good ways down now.... only because I have changed to 357 Sig... but then I've got one heck of a supply of 9mm ammo and a few 9mm pistols and rifles...

I have changed to 357 Sig...

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I think that's do-able in an AR :wink:

It was also designed and does tumble creating a larger wound channel.

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I believe that was a bit of an "accident". As I understood, the slow twist of the early M-16's barely stabilized the bullet and that resulted in the tumbling upon impact. Later versions of the rifle had a faster twist and the bullet lost that attribute.

I have a marlin Camp 9 and with good supply of 20 round magzines, I would feel fine using it for home defense. Mine prefers 124 grain brass ammo and I use Federal HST for HD.
In a close quarters home defense scenario, The 16.5 inch barell manuevers better in tight spaces than my other rifles,low recoil makes second shots quicker, and hollowpoints will hopefully stay in the bad guy and not tumble out of my home.