Anyone own both an AR-15 and an AK-47?

[possum]

i will tell you that i have shot and or heard alot of ak/ pk/rpk/ ar/m4/saw/m240 and others., both out going and in comming, and i have honestly never stopped and took the time to figure out which one is louder or not, however i can tell the differnce when i hear them shot at, near me or even at a distance.

 

[El Clerkino]

i will tell you that i have shot and or heard alot of ak/ pk/rpk/ ar/m4/saw/m240 and others., both out going and in comming, and i have honestly never stopped and took the time to figure out which one is louder or not, however i can tell the differnce when i hear them shot at, near me or even at a distance.

sums up my expertise, As everyone else has said they are 2 distinct different sounds the only thing I can add is they sound similar if you are on the receiving end and the rounds are close and then it sounds more like pronounced firecracker, if that makes sense. Its a distinct noise that you don't forget.

 

[ShamWow]

Which one is louder at distance is a very subjective thing. How far? Is it hot or cold, humid as all hell or pretty dry? Are you in a grassy field or in the desert or in the woods?

I guess a good distance to judge would be 1000 yards or something.

 

[dirtymike1]

I think you missed my point of that.


Since I've never heard either at that king of range, my guess would be a faint crack that may or may not be to discernable at that distance. You may here gunshots but you may not be able to determine what gun is shooting.

 

[benEzra]

I take it if they are the same up close they will be equally loud from a distance?

Should be comparable, yes.

What about the military's M4 with its shorter 14.5 in barrel?

14.5" will be louder than 16", all else being equal, and 16" will be louder than 20". You're probably looking at 5dB or so between each of the above (just a rough guess).

But out of a well compensated AR and a slant brake Yugo AK, the AR is louder. Both 16" barrels. The SU-16B is way louder than both, due to no compensator.

Actually, a compensator (muzzle brake) makes a rifle considerably louder, generally by 5 or 10 dB. One of the loudest rifles I've had the displeasure to be near was a 14.5" AR with a brake that someone was using in a USPSA match I was shooting in. A flash suppressor doesn't increase loudness, though, and it seems to me that they do redirect the sound and blast away from the shooter to a small degree.

 

[ShamWow]

14.5" will be louder than 16", all else being equal, and 16" will be louder than 20". You're probably looking at 5dB or so between each of the above (just a rough guess).

M4/M4A1 Carbine I think could be as loud as a 30-06 from a 24" barrel from what I've been told but I'm not sure, I have fired 30-06s before but never fired an M4 so I don't know for sure.

Actually, a compensator (muzzle brake) makes a rifle considerably louder, generally by 5 or 10 dB. One of the loudest rifles I've had the displeasure to be near was a 14.5" AR with a brake that someone was using in a USPSA match I was shooting in. A flash suppressor doesn't increase loudness, though, and it seems to me that they do redirect the sound and blast away from the shooter to a small degree.

Yes a flash suppressor does redirect some noise more downrange than to the shooter.

 

[benEzra]

M4/M4A1 Carbine I think could be as loud as a 30-06 from a 24" barrel from what I've been told but I'm not sure, I have fired 30-06s before but never fired an M4 so I don't know for sure.

That sounds about right. Here are some dB figures:

http://www.freehearingtest.com/hia_gunfirenoise.shtml

Table 2. CENTERFIRE RIFLE DATA
.223, 55GR. Commercial load 18 _" barrel.....155.5dB
.243 in 22" barrel...........................155.9dB
.30-30 in 20" barrel.........................156.0dB
7mm Magnum in 20" barrel.....................157.5dB
.308 in 24" barrel...........................156.2dB
.30-06 in 24" barrel.........................158.5dB
.30-06 in 18 _" barrel.......................163.2dB
.375 — 18" barrel with muzzle brake...........170 dB

That ranks an 18" .223 as slightly quieter than a 24" .30-06, so if you lop off that 18" tube to the 14.5" of an M4, it will likely be at least as loud as the 24" .30-06 (but perhaps not as loud as the 18" .30-06).

 

[ShamWow]

That sounds about right. Here are some dB figures:

http://www.freehearingtest.com/hia_gunfirenoise.shtml

Table 2. CENTERFIRE RIFLE DATA
.223, 55GR. Commercial load 18 _" barrel.....155.5dB
.243 in 22" barrel...........................155.9dB
.30-30 in 20" barrel.........................156.0dB
7mm Magnum in 20" barrel.....................157.5dB
.308 in 24" barrel...........................156.2dB
.30-06 in 24" barrel.........................158.5dB
.30-06 in 18 _" barrel.......................163.2dB
.375 — 18" barrel with muzzle brake...........170 dB

That ranks an 18" .223 as slightly quieter than a 24" .30-06, so if you lop off that 18" tube to the 14.5" of an M4, it will likely be at least as loud as the 24" .30-06 (but perhaps not as loud as the 18" .30-06).

Nice find.

Too bad that don't have any 7.62x39, also that .223 is only for 55gr, the 62gr might be a bit louder.

One way to tell how loud they are and which can be heard farther is by the echo as the sound waves bounce back, the longer the echo the farther it will carry.

But that is a very subjective thing because the echo will depend greatly on the environment, like open fields or wooden terrain.

So if an AR and an AK are fired in the same terrain, which has a louder or longer echo? Like in the woods for example.

Just my thoughts.

 

[benEzra]

Too bad that don't have any 7.62x39, also that .223 is only for 55gr, the 62gr might be a bit louder.

They do have .30-30, which is comparable to 7.62x39mm ballistically; I'd expect the sound level to be rather similar to 7.62x39.

Also, I would expect that a 55gr load would if anything be marginally louder than 62gr due to the higher velocity, though I've never noticed much of a difference in sound between 55gr and 62gr myself.

 

[ShamWow]

They do have .30-30, which is comparable to 7.62x39mm ballistically; I'd expect the sound level to be rather similar to 7.62x39.

Also, I would expect that a 55gr load would if anything be marginally louder than 62gr due to the higher velocity, though I've never noticed much of a difference in sound between 55gr and 62gr myself.

Doesn't the 55gr and 62gr both have the same muzzle velocity? 3000 ft per second?

30-30 does have a bit more powder though than the +25 grains of powder for the 7.62x39 or the 5.56x45.