Hello I have a question.

[CheckMyBrain]

I currently do not have an AR-15 but I hope someday I will buy one once I save up the money.

I'm just curious which has a louder report and sounds louder from a distance/louder echo, an M4/M16 in 5.56x45 or an AK-47 in 7.62x39?

The noise does not bother me and I wear hearing protection when I shoot anyway but I'm still curious.

Anyone fired both weapons? Anyway thank you for taking your time to read and answer my question and good day.

[ChicagoTex]

7.62x39 is louder, but 5.56x45 is sharper.

[CheckMyBrain]

Aren't both the 5.56x45 and 7.62x39 loaded with about the same amount of powder?


And wouldn't the higher gas pressure and higher muzzle velocity make the 5.56x45 louder?

[faithmyeyes]

The way I understand it, the noise a gun makes when fired comes from

1. Hammer snap, action cycling, etc... anything that moves or rubs as the weapon operates.

2. Release of gas pressure as the bullet exits the barrel, and the characteristics of that pressure impulse. This is affected by the actual pressure at the muzzle and how quickly (and along what paths) it's released. Powder charge, barrel length, and any muzzle device all are factors - not just bore diameter.

3. Sonic crack of a supersonic bullet.

If you just wanted to know which of two particular weapons was louder, you could test with a quality peak-holding sound-pressure level (SPL) meter at some given distance. However, things like the characteristics of the report, likelihood of echo, and audibility at a distance can change minute-to-minute based even on the terrain around you and the atmospheric conditions.

[CheckMyBrain]

The way I understand it, the noise a gun makes when fired comes from

1. Hammer snap, action cycling, etc... anything that moves or rubs as the weapon operates.

2. Release of gas pressure as the bullet exits the barrel, and the characteristics of that pressure impulse. This is affected by the actual pressure at the muzzle and how quickly (and along what paths) it's released. Powder charge, barrel length, and any muzzle device all are factors - not just bore diameter.

3. Sonic crack of a supersonic bullet.

If you just wanted to know which of two particular weapons was louder, you could test with a quality peak-holding sound-pressure level (SPL) meter at some given distance. However, things like the characteristics of the report, likelihood of echo, and audibility at a distance can change minute-to-minute based even on the terrain around you and the atmospheric conditions.

So what if both weapons were both in the exact same terrain such as in the mountains or in an urban city and with the same atmospheric conditions, what would be louder than?

[CheckMyBrain]

Is the high velocity crack of the 5.56 louder at a distance than the slower 7.62x39?

[JonnyVain]

you should search the archives. There was just a thread about this within the past month. Lots of info in that one.

OH heck, I dont even remember if it was in the general forum or AR general.

Barrel length has a lot to do with it. Where you're standing relative to the rifle has a lot to do with it. Muzzle device has a lot to do with it. Are you talking sound relative to the shooter, people standing around, or in general?

Most people will say the M4 is louder than the AK, but the M16 might be quieter than the AK. And as said before, the AR is more of a crack compared to the boom of an AK.

I've never compared at a distance, but my brother tells me the AR carries more.

[CheckMyBrain]

you should search the archives. There was just a thread about this within the past month. Lots of info in that one.

OH heck, I dont even remember if it was in the general forum or AR general.

Barrel length has a lot to do with it. Where you're standing relative to the rifle has a lot to do with it. Muzzle device has a lot to do with it. Are you talking sound relative to the shooter, people standing around, or in general?

Most people will say the M4 is louder than the AK, but the M16 might be quieter than the AK. And as said before, the AR is more of a crack compared to the boom of an AK.

I've never compared at a distance, but my brother tells me the AR carries more.

What kind of AR-15 does your brother have and what barrel length? Just wondering.

[545Warman]

Yes the 7.62x39 is louder up close, but the crack of the 5.56 will be heard farther in stock barrel lengths

On another note, some forms of auto racing is a lot louder than shooting normal cal.s, but most people don't wear ear protection while watching auto racing.

[CheckMyBrain]

Yes the 7.62x39 is louder up close, but the crack of the 5.56 will be heard farther in stock barrel lengths


Must be the open ports of the AK that could make it louder up close, but the faster 5.56 gives it that sharper sound making it louder overall.

[CheckMyBrain]

So the sharper crack sound of the 5.56 will travel farther than the sound of the 7.62x39?

[JC0352]

You haven't found an answer yet?!

http://forums.gunboards.com/showthread.php?155699-Random-question-about-M4-vs-AK47&p=1207518
http://forums.militaryspot.com/eve/forums/a/tpc/f/746104564/m/116104313
http://militarytimes.com/forums/showthread.php?t=1576160
http://www.militaryphotos.net/forums/showthread.php?173895-Random-question-anyone-in-or-was-in-the-military
http://www.defencetalk.com/forums/army-security-forces/im-doing-some-research-military-weapons-9651/
http://www.thefiringline.com/forums/showthread.php?p=3929698
http://shootersforum.com/showthread.htm?p=485100
http://forums.military.com/eve/forums/a/tpc/f/69719858/m/4860015242001

[rifleman2000]

You haven't found an answer yet?!

http://forums.gunboards.com/showthread.php?155699-Random-question-about-M4-vs-AK47&p=1207518
http://forums.militaryspot.com/eve/forums/a/tpc/f/746104564/m/116104313
http://militarytimes.com/forums/showthread.php?t=1576160
http://www.militaryphotos.net/forums/showthread.php?173895-Random-question-anyone-in-or-was-in-the-military
http://www.defencetalk.com/forums/army-security-forces/im-doing-some-research-military-weapons-9651/
http://www.thefiringline.com/forums/showthread.php?p=3929698
http://shootersforum.com/showthread.htm?p=485100
http://forums.military.com/eve/forums/a/tpc/f/69719858/m/4860015242001

Lol. He is getting the most possible sources for the most accurate answer.