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View Full Version : I have a question on the military M4 and AK47.



CheckMyBrain
01-26-10, 12:38
Does both the M4/M249/M16 in 5.56x45 NATO and AK47 in 7.62x39 have a distinctive sound when fired? Which is louder?

How loud are they at a distance like 800m away?

Would anyone know the decibel levels?

I'm asking this because the 5.56 is faster and is loaded to be hotter or steamier with the higher gas pressure so I'm just curious.

JonnyVain
01-26-10, 13:45
I don't know numbers, but most people say the AR is louder than the AK. That said, barrel length/muzzle device has a lot to do with noise for the user and those around. But as far as from a distance or from the business end, I believe the AR is, overall, louder. I've never been on the business end though.

CheckMyBrain
01-26-10, 14:07
I don't know numbers, but most people say the AR is louder than the AK. That said, barrel length/muzzle device has a lot to do with noise for the user and those around. But as far as from a distance or from the business end, I believe the AR is, overall, louder. I've never been on the business end though.

I assume it is the higher muzzle velocity and gas pressure maybe?

rifleman2000
01-26-10, 14:31
Barrel length has a lot to do with it. Shorter barrels are louder because more unburnt powder exits the barrel, also causing a larger muzzle flash. M4s are distinctly louder than M16s.

SGT D USMC
01-26-10, 16:21
I think that the m4 is louder if you are standing next to the shooter, I think the AK noise carries further.

CheckMyBrain
01-26-10, 16:55
Barrel length has a lot to do with it. Shorter barrels are louder because more unburnt powder exits the barrel, also causing a larger muzzle flash. M4s are distinctly louder than M16s.

So I think its safe to say the M4 with its 14.5 in barrel is also slightly louder than the AK with its 16 in barrel correct?


I think that the m4 is louder if you are standing next to the shooter, I think the AK noise carries further.

Lower frequencies radiate more but dissipate amplitude faster than high frequencies so the higher pitch sound should sound louder at a distance.

bulbvivid
01-26-10, 17:50
This is the AK-47 assault rifle, the preferred weapon of your enemy; and it makes a distinctive sound when fired at you, so remember it. -Gunny Highway

Dunderway
01-26-10, 20:00
As far as decibels go, I wouldn't know.

I would describe them as an M4 being more trebble(snap) and an AK being more bass (thump). Similar to a 9mm vs. 45acp.

Gutshot John
01-26-10, 20:08
Because the AK47 has a significantly bigger bore wouldn't more powder be burned inside the barrel?

I would guess that the AR is louder for that reason but I have no way of quantifying that.

RogerinTPA
01-26-10, 20:14
I always thought the AK was louder to me. I was once firing my AK variant between a guy with a AR Carbine and a guy with a SOCOM-14. Every time I fired, both jumped like I stuck them with a cattle prod. The AK sounded as loud as the SOCOM to me.

Trajan
01-26-10, 21:21
I can say that an AK in 5.56 is louder than an AR in 5.56 both with 16" barrels.

Was probably due to the lack of a muzzle device in the AK.

rifleman2000
01-27-10, 07:42
I can say that an AK in 5.56 is louder than an AR in 5.56 both with 16" barrels.

Was probably due to the lack of a muzzle device in the AK.

Muzzle brakes make it louder for shooters and those to the side.

Captains1911
01-27-10, 08:02
Most say the AR is louder, and I would have to agree after hearing them both being fired at the same time. The AR is more of a "crack" whereas the "AR" is a "boom".

ForTehNguyen
01-27-10, 08:22
yes they make very distinctive noises. Not that we really get to experience this but their cyclical rate is very distinctive too.

I have an AMD65 AK and that things loud because of the muzzle brake, makes a mean flash too :D

Ridge_Runner_5
01-27-10, 08:43
My buddy did two tours in Iraq. Last summer we went to the range and shot our ARs...someone at the other end of the range fired a few rounds from an AK, and my buddy definately noticed it. Popped his head up and scanned around himself.

So yeah, they are distinct.

Alex V
01-27-10, 09:26
This is funny because I was just talking about this with my GF.

When she stands behind me while I shoot, she says the AR [14.5" with brake NOT flash hider] is louder than the AK [no muzzle device]

When shooting, she sais the AK is louder over all, between the action and the firing of the weapon itself.

I happen to agree.

I have no explination as to why, simply my observation with my two rifles.

rifleman2000
01-27-10, 09:45
This is funny because I was just talking about this with my GF.

When she stands behind me while I shoot, she says the AR [14.5" with brake NOT flash hider] is louder than the AK [no muzzle device]

When shooting, she sais the AK is louder over all, between the action and the firing of the weapon itself.

I happen to agree.

I have no explination as to why, simply my observation with my two rifles.

That is because the muzzle break directs gas and sound out away from the weapon. Weapons with muzzle breaks are louder for bystanders, depending on location, than the shooter. I can't diagram the sound pattern for you, but that is how it works.

All rifles are louder if you are to the side, and not behind them. Muzzle breaks make it worse.

John_Wayne777
01-27-10, 09:47
Gunny Highway is not amused.

CheckMyBrain
01-27-10, 10:49
Because the AK47 has a significantly bigger bore wouldn't more powder be burned inside the barrel?

I would guess that the AR is louder for that reason but I have no way of quantifying that.

I think the 5.56 and 7.62x39 has similar powder loadings actually.


I can say that an AK in 5.56 is louder than an AR in 5.56 both with 16" barrels.

Was probably due to the lack of a muzzle device in the AK.

Different design maybe? Maybe more gas gets vented out of more open areas making it louder for the shooter since the AK is a lose build.


Most say the AR is louder, and I would have to agree after hearing them both being fired at the same time. The AR is more of a "crack" whereas the "AR" is a "boom".

Do you mean AR=CRACK and AK means BOOM?

You put AR for both, must be a typo.

CheckMyBrain
01-28-10, 16:38
So which would sound louder at a distance the sharper "crack" of the 5.56 or the deeper "boom" of the 7.62x39?

Can they be heard a mile away?