I have a question.,,,,,, - Page 1

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[ARCHIVED THREAD] - I have a question.,,,,,,

Posted: 10/23/2018 2:47:55 PM EDT

What makes one AR louder than another given the same specs ?
So I bought my son a Fire 4 effect AR for his 8th grade graduation . They are supposedly made by CMMG . It has a 1:7 free float barrel with carbine gas system and standard A2 birdcage, it shoots well and has been trouble free so far . My only complaint is that the muzzle blast is WAY louder than either my Colt 6920 or my PSA with the exact same specs . 16 inch carbines with A2s .

Posted: 10/23/2018 5:37:43 PM EDT

[#1]

If it's the same ammunition and muzzle device I'm not sure.

I notice different ammunition will cause a louder report/different.

Posted: 10/23/2018 8:12:55 PM EDT

[#2]

Quote History

Quoted:
If it's the same ammunition and muzzle device I'm not sure.

I notice different ammunition will cause a louder report/different.

View Quote

Yes, same ammo , same muzzle device, same length barrel and gas system .

Posted: 10/23/2018 9:00:05 PM EDT

[#3]

Could it have to do with the bore diameter? Wouldn’t a slightly tighter barrel have more back pressure, which would make it louder?

Posted: 10/30/2018 9:14:04 PM EDT

[#4]

Gas port sizes?

Posted: 10/31/2018 10:20:11 PM EDT

[#5]

I had a similar issue with a CDNN upper I bought. I ended up changing the gas block and tube to solve the issue. I found it by wrapping a towel around the block as I fired it.

Posted: 11/3/2018 6:15:33 PM EDT

[#6]

Gas leak makes sense, people say XCRs are louder than ARs. XCRs are long stroke with the gas venting at the piston/gas block.

Posted: 11/4/2018 10:17:49 AM EDT

[#7]

It could be as simple as the sound report is different between a shooter's or bystander's position. Are you observing both rifles from the same position?

Posted: 11/5/2018 12:20:52 PM EDT

[#8]

Quote History

Quoted:
It could be as simple as the sound report is different between a shooter's or bystander's position. Are you observing both rifles from the same position?

View Quote

That is not it . We were shooting at our property and my cousin and his buddy drove up from the cabin to see what we were shooting because it was so loud !

Posted: 11/5/2018 4:35:01 PM EDT

[#9]

Perhaps any number of things that affect the speed at which the gas system works. Weight of the buffer, weight of the BCG, gas port...... a faster cycle would open up the action faster post detonation releasing more noise. But I am no expert on the matter.

Does one have a FA BCG and one have a SA BCG?

Posted: 11/6/2018 4:19:36 AM EDT

[#10]

Well then...it's 1) tighter chamber causing higher pressure, 2) a faster unlock [caused by #1, a lighter buffer weight or lighter bcg], 3) a leak at the gas port, or 4) a combination.

Posted: 11/13/2018 3:00:08 PM EDT

[#11]

Double post

Posted: 11/17/2018 10:04:55 PM EDT

[#12]

Quote History

Quoted:
I had a similar issue with a CDNN upper I bought. I ended up changing the gas block and tube to solve the issue. I found it by wrapping a towel around the block as I fired it.

View Quote

This (ie, gas leak) is the only explanation so far that makes any sense, given that the other rifles are using same ammo, same barrel length, same muzzle device.

[ARCHIVED THREAD] - I have a question.,,,,,,

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