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I have fairly long experience of the AR platform as a rifle, but am completely new to ARs in pistol length.
I’ve got 3 ARs in rifle configuration, 2x 5.56 and 1 .22, so I’m thinking about a pistol.
The longest range I expect to engage regularly will be 250 yards.
What am I giving up going with a 7.5 barrel vs a 10.5?
https://www.ar15.com/forums/ar-15/7-...ch/122-723691/
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General consensus, for good reason, is to not drop below 10.3 on a 5.56 AR. Both for terminal effectiveness of the round and function of the weapon. If you want to go under 10.3, get a 300 BLK upper. Otherwise, 10.3-12.5 is a solid range for 5.56 shorties.
From the link above: "LOUD. Even with ballistic shooting glasses, the concussion hurts my eyes."
That pretty much sums up the disadvantage of a 7.5" 5.56/.223.
Andy
This. You lose ALOT below 10". Get a really nice barrel in that 10.3-12.5" range, shoot it, carry it alot...and you'll fall in love with it. I did, 11.5".....it can still do most of what a longer barreled gun can do, and ridiculously light and handy.Quote:
Originally Posted by Wake27
No kidding about the weight - my 11.3" pistol has a BA Hanson .750 barrel, not a pencil profile, and weighed just under 6 lbs before I added a RDS and light.
Andy
I think 11.5 is a sweet spot for many.
Thanks to all for the suggestions. I went with the 7.5 because that was all they had in stock at my price point.
I didn’t see any point in paying 2.5x the price, for an admittedly higher tier gun, which was the next closest option. They may have been better yin’s in some respects, but not 2.5x better... I could buy two more uppers for that price.
...and I didn’t see any point in waiting to see what they got in.
I’ll play with the 7.5 and possibly buy a 10.5 upper when prices are more reasonable... if they ever are.
https://youtu.be/TUVJwoDtcnA
Solgw and pressburg discuss barrel lengths
I have two AR pistols. A 5.56 with an 8.5" barrel and a 7.62x39 with an 11" barrel. I will agree that it is preferred to have a longer barrel 10.3+ inch barrel for the 5.56 if you are going to shoot out to 250. I still think that my 8.5" barrel using Black Hills 50-grain TSX and/or 75 grain soft point ammo would be effective in ending a threat 125 yards and in.
Agreed. Little more dwell time and a couple extra fps.Quote:
Originally Posted by opngrnd
While certainly not technical feedback, this is the wrong time to be spending $$$ on an AR pistol. To be truthful not even 16" AR's are likely to be safe, but "pistols" are low-hanging fruit and easily picked. YMMV.
To render more technically-related info? As others have said, going below 10.5" is not desirable or optimal, both for ballistics and function.
I would posit they're ALL in some danger at this point.
What does this mean?Quote:
Originally Posted by ABNAK
Biden has said he'll make all semi-automatic rifles Class III weapons.Quote:
While certainly not technical feedback, this is the wrong time to be spending $$$ on an AR pistol. To be truthful not even 16" AR's are likely to be safe, but "pistols" are low-hanging fruit and easily picked.
HE doesn't understand what he's talking about, but his handlers do...
^^Agreed^^
I heard being loud a lot before I got my DDM4 10.3" AR Pistol.Quote:
Originally Posted by AndyLate
It has proven to be a myth. If louder than 16" barrel I can't tell and zero concussion....
Your experience is different than mine. Neither your experience or mine proves or disproves anything. I cannot tell a real difference between a 16" or 14.5" AR, but my 11.3" has noticeably more concussion.Quote:
Originally Posted by Whalstib
This article also disagrees with you: http://www.sadefensejournal.com/wp/b...-nato-weapons/
If you have quantifiable proof that the sound level or muzzle pressure is the same with a 10.3" and 16" 5.56, feel free to share the data.
I could also point out the OP and my post are referencing 7.5" barrels.
Andy
Actually it says...Quote:
Originally Posted by AndyLate
"Actual sound pressure levels varied from 162.5 dB(A) in the 24-inch barrel to 165.1 dB(A) in the 5-inch barrel." Almost reads like a misprint as I'd have guessed a much greater difference from a 24" to a 5"! 16" to 10" I seriously can not tell the 10" is much louder
Plus the article is dealing with effects on suppressors....Maybe it correlates to unsuppressed.....
Anyways....As I said it's not a very discernible difference and no reason to avoid a shorter barrel. Other factors would be more important IMO.
Cool article! Thanks!
I'm not questioning whether you notice a difference. A 10.3" barrel using the same muzzle device and ammunition as a 16" barrel will be measurably louder. I, like most people on the planet, can detect a difference as well.Quote:
Originally Posted by Whalstib
FYI - there is a significant difference between 162.5 and 165.1dB, certainly detectable by most people. 2.5 dB is roughly a 25% increase in perceived loudness. Also from the article "the sound measurements are not considered overly accurate due to compliance with the Mil-Std."
To be clear, the quote I found amusing and provided was, like the OP, referencing a 7.5" 5.56 barrel.
Andy
I will say that my favorite rifle is my 11.5. But I will not shoot that sum bitch without a suppressor. Anyone saying that sbr’ s aren’t louder ain’t shooting mine. My 11.5 bcm is freaking so loud and concussive that at my local range, where it’s isn’t uncommon for multiple magnum rifle calibers are shot at the same time, people stop me look at me like I’m shooting a cannon. I would defiantly go 11.5 to 12.5 range if it were me.
Wow!Quote:
Originally Posted by chamber143
I'm telling you my DDM4 10.3" is NO LOUDER than a 16" AR! I feel no concussion....no ill effects and have never considered a suppressor....
Perhaps there is something with the design....
I wear plain old $20 Howard Leight ear muffs.....don't even bother with adding in ear protection. I'm a musician and pay attention to my hearing and can say I suffer no ill effects from the 10.3" DDM4...
YMMV
I recently took,a two day class and halfway through the class day 1 I thought that the suppressor was wearing my arms out so I took it off. I fired 5 rounds and said fuk this and put it back on. It’s a loud bitch. I wish mine wasn’t any louder than my 16 inches.Quote:
Originally Posted by Whalstib
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dB scale is logarithmic. 10dB = twice as loud
Also humans vary as to their perceived sensitivity.
Some will go to heavy metal concert and stand in row one. Others can’t stand to be in the parking lot.
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Interestingly, 3dB is actually twice the pressure, but 10dB is typically *perceived* as twice as loud.Quote:
Originally Posted by wscottstewart
I believe a doubling of pressure is 6dB, while a doubling of power is 3dB.Quote:
Originally Posted by georgeib
I suppose it's an individual thing. With hearing protection I have no issue with my AR pistols. Even my little 8.5". It's louder than a carbine but not by all that much. It has a KV linear comp. All others are A2 or A1 flash hiders. One of the A2s is extended. These are all 5.56 sharing same type ammunition.
Kind of an interesting article here. The author is a Doctor (and Professor) who actually discussed supressors without bias, which is refreshing.
She states that SBRs were measured at 170dB and that some muzzle brakes increased the SPL to 180 - 185 dB (!).
For comparison, 165dB is the number generally thrown around for a 16" AR.
https://www.hearingreview.com/inside...g-conservation
This article shows a 9mm pistol SPL as 5 dB greater than a .22 lr pistol. I don't know anyone who thinks they are equally loud - 5 dB is detectable.
https://www.nationalguntrusts.com/bl...-of-firearms-2
Andy
P.S. I am guessing SBR means a 5.56mm in the Dr's study.
Have you guys tried a KAK can, Indian Creek can or similar? Not a suppressor, a can.
Youtube guys say they are effective at sending the noise and concussion forward.
My 8.5" pistol with Gamma V6 is loud, but tolerable to me with hearing protection. My 11" 7.62.39 pistol is not nearly as loud.
Yes, I have one (KAK) on my 7.5". I like it & it seems to at least make it the same as my 10.5". Truth be told, I don't really have any problem's with any of my AR pistol's, but don't shot them at indoor range's. As a matter of fact, I typically shoot by my self always, anyway.Quote:
Originally Posted by j102
I have a BRT Covert Comp (linear compensator) on my 11.3" 5.56 and a KAK "Slimline Mini" flash can on my 10" 9mm. I also only shoot outdoors, but they both seem to push the concussion downrange a bit. I'm not really convinced it matters on the 9mm.
Andy
How is the flash with that BRT CC compared to an A2?Quote:
Originally Posted by AndyLate
Check this: https://www.thetruthaboutguns.com/ar...ider-shootout/Quote:
Originally Posted by flenna
A2 FH: 0.48 lux
BRT CC: 2.21 lux
Precision Armament AFAB: 0.56 lux
These are measured from two feet aside and ahead of the muzzle, so more a "downrange" data set and somebody would need to retest for "Shooter's View."
Attachment 66011Quote:
Originally Posted by Diamondback
2nd brightest "flash hider" they tested in this particular test.
I have never run an A2 on my 11.3, but the BRT is pretty flashy.Quote:
Originally Posted by flenna
I am pretty spoiled though - my 16 and 18" ARs run A2, YHM Phantom, or AAC Blackout flash hiders.
I don't remember seeing a flash in the daytime when I had the BRT on a 20" barrel.
Andy
Anyone tried the Kaw Valley Magnum--the big 3.25"-er--on a SBR or pistol?