Barrel Sound Signature

[Spencer]

Here is a list of many barrels, from quietest to loudest 12' from the left side of the barrel


First number is 12' to the left reading second number is 12' infront of the barrel
70.93 -----72.91 PPS
71.59 -----73.44 SLY
71.62 -----75.3 Kaner
72.42 -----74.92 SP Teardrop
72.78 -----82.73 SM-1
72.81 -----76.18 Matchstik
73.12 -----74.86 Trilogy
73.19 -----84.60 Custom Products
73.45 -----79.83 Empire 7pc
73.84 -----75.78 Freak 16"
73.88 -----86.58 Empire Revolver
74.05 -----76.63 Un1Tec
74.33 -----80.73 Scepter
74.31 -----76.10 Freak 14"
74.53 -----81.81 Redz pepperstick
74.84 -----76.36 Phat
74.92 -----89.36 TI Longbow
74.96 -----81.97 Dye Ul
76.06 -----76.71 Hammerhead
77.53 -----75.06 Freak 10"
80.47 -----89.17 Pipe
And just proof that unported barrels ARE louder..
84.38 -----91.68 99 Autococker stock (unported barrel)


Here is a list of the barrels from quietest to loudest at 12' infront of the barrel.

70.93 -----72.91 PPS
71.59 -----73.44 SLY
72.84 -----73.75 Proto Stock
73.12 -----74.86 Trilogy
72.42 -----74.92 SP Teardrop
77.53 -----75.06 Freak 10"
71.62 -----75.30 Kaner
73.13 -----75.42 Xmag stock
73.84 -----75.78 Freak 16"
74.31 -----76.10 Freak 14"
74.84 -----76.36 Phat
74.05 -----76.63 Un1Tec
76.06 -----76.71 Hammerhead
73.45 -----79.83 Empire 7pc
74.33 -----80.73 Scepter
74.53 -----81.81 Redz pepperstick
74.96 -----81.97 Dye Ul
72.78 -----82.73 SM-1
73.19 -----84.60 Custom Products
73.88 -----86.58 Empire Revolver
74.69 -----87.64 JJ Edge
80.47 -----89.17 Pipe
84.38 -----91.68 99 Autococker stock (unported barrel)

--------------------------

Lets come up with theories on why some are quieter than others.

Here is what I came up with,

MATERIALS

If Im correct, I did fail chemistry..

Palmers Barrel is made out of brass, known to be denser than aluminum, However next in line is the sly, and its carbon fiber known to be less dense than aluminum..

Porting & Length

Usually longer barrels are quieter, my belief is that a longer barrel allows the air that is propelling the ball more volume and we all know that when you take a pressure and give it more volume the pressure drops. Sound = pressure, thats why a silencer works, it drops the pressure thats exiting the firearm from around 1200 or so psi? to 60 psi..

Now how many ports?
How big should the ports be?
Where should the ports begin?

What do you guys think?

Using whatever knowledge you guys have... I know Tom wrote a big article about pressures in the barrel that should really help. Any imput you guys can have would help..

[trevorjk]

what was the foundation for the test? what did you use to measure the decibel levels? what gun where you using? velocity you were shooting at? ect ect, this is intriguing

[Spencer]

Sorry though you saw this, its a test of many paintball barrels.

Enjoy..

http://www.pbnation.com/showthread.php?t=2218018

[muzungu_mbaya]

I thought GP used brass to make his barrels. Copper isn't practical as it's too soft and machines very poorly.

[Spencer]

I thought GP used brass to make his barrels. Copper isn't practical as it's too soft and machines very poorly.

Im an idiot.. Your correct, I first said it was nickle remember it was brass and then went back to type brass and typed copper... Sorry.

[muzungu_mbaya]

If you can get a hold of an Ego barrel, I'd like to see that. My 08 Ego sounds like a Spyder, but when I put my MatchStik on, it quiets down a lot. However, there's a bore difference of .004 between the two, so that could be a big part of the reason.

[ThePixelGuru]

Hmm. Couple questions before these results could be considered meaningful.

How many trials did you do with each barrel? What brand of paint did you use? Did you measure the size of the balls beforehand, and if so, do you have those measurements?

I bet ball size has a lot to do with it - it would be my hypothesis that overbored paint would be louder than underbored paint.

[Mechanic79]

Hmm. Couple questions before these results could be considered meaningful.

How many trials did you do with each barrel? What brand of paint did you use? Did you measure the size of the balls beforehand, and if so, do you have those measurements?

I bet ball size has a lot to do with it - it would be my hypothesis that overbored paint would be louder than underbored paint.

I'm thinking these same thoughts/questions.

Nice findings regardless.

[MANN]

Hmm. Couple questions before these results could be considered meaningful.

How many trials did you do with each barrel? What brand of paint did you use? Did you measure the size of the balls beforehand, and if so, do you have those measurements?

I bet ball size has a lot to do with it - it would be my hypothesis that overbored paint would be louder than underbored paint.

used ~ 6 types of paint & reballs. we measured many of the paintballs (took a sample study).. All of this stuff is listed in the "test"

[ThePixelGuru]

used ~ 6 types of paint & reballs. we measured many of the paintballs (took a sample study).. All of this stuff is listed in the "test"

I meant Spencer's test, which is separate from yours... or is this all data from the same test?

[MANN]

I meant Spencer's test, which is separate from yours... or is this all data from the same test?

all mine. he just copied and pasted.

[Spencer]

all mine. he just copied and pasted.

Yes, sorry, I did not claim this as my own, I thought I stated that somewhere..

All I did was arranged the numbers in order from least to greatest. I had no input in the tests. Never met man..

[Spider-TW]

all mine. he just copied and pasted.

You mention the actual versus the advertised bore dimensions. I looked for it in there (pbn), but didn't see any comparisons. Did I miss it?

**edit** I forgot about post #7 while I was reading elsewhere. Maybe someday?

Also, while you have all that fresh data on ball sizes, would you be able to throw out some standard deviation numbers? I would be nice to know what the manufacturers are holding lately.