Paul,
If one shoots at 100 yards, then what's the purpose of mentioning the ballistic test at 800 meters? I understand your ballistics comparison between both rounds, but I don't think that's applicable here. Your comparing the ballistic testing of two different rounds chambered for two different weapons, while I'm talking about trigger time! But to each their own! Are there better choices than 9mm for "long range", you bet! Can you save a few bucks shooting 9mm, if you don't reload or choose to safe a few bucks, you bet!
My point is a 9mm AR has a maximum effective range of ~100 yards, while a "normal" AR tends to be in the 500-800m range (depending on barrel length, twist rate and ammunition.) The Lee Hand Press makes reloading a "while you watch Netflix" proposition- and really "savings" is what you make of it-- I tend to shoot a lot less ammo at 300m targets than I do at 100m targets, so I'm not sure that the economic argument really holds a lot of water. Then again, I don't tend to use the 100rnd magazine at targets 300m and up
A .22 conversion is also dirt cheap to shoot, so why specifically choose 9mm? If choosing 9mm, why choose an AR-15 platform?
Personally, I think the AR-15 platform is sub-optimal for 9mm- I think there are better options in carbines that shoot 9mm[1], and frankly, I'd rather shoot 55gr milsurp 5.56mm in a carbine- the economics aren't that big a difference but the ability to go say from an M4 upper to an HBAR upper depending on need without worrying about magazines makes it more of a winner in my book. The main advantage of the AR platform is the ability to easily switch upper receivers unless you're just into hanging things off the handguards- but going 9mm really, really, really wants a dedicated lower since you need to change out the hammer and possibly the recoil buffer as well to make it feed reliably.
Just because I mentioned shooting cost a lot of money doesn't mean I need to shoot a pellet gun to watch my pennies. If you prefer shooting .223 at 100 yards and I enjoy shooting 9mm at 100 yards, then so be it. Also, What about the shooter who doesn't reload, like me?
What I'm saying is if your argument for 9mm is economic (because I think we can agree it's not ballistics) then there are cheaper options than 9mm.
The interesting thing about the AR-15 platform is that the lower receiver i the registered "firearm" part. So outside of the 11.5"/12.5" short barrels, you don't need any paperwork at all to change calibers if you're using a standard .223/5.56mm lower. When you choose a caliber that really needs specific parts you're losing the value of the platform. At that point a platform actually designed for a pistol caliber is a better choice in my opinion.
More importantly, I find a lot of other cartridges more interesting. Here's a list of what you can potentially use in an AR-15 platform:
5.45x39mm, 5.56×45mm NATO, 6mm TCU, 6x47mm, 6mm PPC, 6mm Whisper, 6mm WOA, 6mm Hagar, 6mm BR Remington, 6×45mm, 6.5mm Whisper, 6.5mm Grendel, 6.5mm PPC, 6.5 WSSM, 6.5 WOA, 6.8 mm Remington SPC, 7mm Whisper, 7mm TCU, 7.62×39mm, .17 Remington,
.17-223, .17 HMR, .17 HM2, .204 Ruger, .20 Tactical, .20 Practical, .20 VarTarg, .221 Fireball, .22 LR, .22 WMR, .222 Remington, .222 Remington Magnum, .223 Remington, .223 Remington Ackley Improved, 223 WSSM, .243 Winchester, 243 WSSM, .25 Winchester Super Short Magnum, .25x45mm, .30 Remington, .300 Whisper, .30 Herrett Rimless Tactical, 300 AAC Blackout (7.62×35mm,) .30 RAR, 300 OSSM, .30 Carbine, .308 Winchester,.338 Whisper, .338 Lapua Magnum,.35 Gremlin,.358 WSSM, .450 Bushmaster, .458 SOCOM, .50 Beowulf, .50 BMG, FN 5.7×28mm, 7.62×25mm Tokarev, 9×19mm Parabellum, 9x21, 10mm Auto,.357 Sig, .40 S&W, .400 Corbon, .41 Action Express, .45 GAP, .45 Super, .45 ACP, .45 Winchester Magnum, .50 Action Express.
Personally, I'm just saying that there are a *lot* more interesting rounds on that list than 9mm Parabellum. Lots of them don't require a different hammer and/or recoil buffer. Most of the ones that require a dedicated lower are way more interesting than 9mm in my book.
Thanks for the info about federal green tip 5.56mm! I haven't tried it. Obviously, you like the ammo enough to recommend it, so it must be good stuff! Regardless, happy shooting!
Federal makes good stuff, though Black Hills is my fav. commercial ammo.
Paul
[1] CX4, Vector Uzi clone, and HK94 to name just three I'd take over an AR.
