Barrel Testing Archives - Volume test

Volume is a tricky subject to fully understand in paintball, a LOT of factors are involved ranging from the marker to the barrel to the very paintballs you use, for the purpose of this article we will be focusing only on the barrel.

Even with only looking at the barrel there are still several factors involved, the main factors being

  • Porting
  • Bore size
  • FPS
  • Barrel Length
  • Muzzle Break / Barrel tip

*note* several sets of test data are included here, these sets of data were all taken at different times and cannot be compared against each other as different factors may have been at play (for example on one test the sound meter may have been 5 feet away, and on another 7 feet) Data is only comparable to data within the exact same test on the same sheet.

1) Porting

Porting as most people allready know is the easiest thing to look at when it comes to volume, its quite simple actually, more porting = lower volume, less porting = higher volume. Unfortunatly it sometimes gets a bit more complicated then the sheer number of holes, factors that can affect the overall volume include both how much porting total is in the barrel, where the porting starts, and does the porting change after it is introduced

Below is a quick test done with 5 different barrels, all barrels are 12" long and made to the exact same specifications with the only difference being the porting method.

  • Un-ported (no porting at all)
  • Standard Ported 4 rows porting
  • Double ported (8 rows of 3" porting)
  • SQB (4 rows of 3" porting and 4 rows of just over 6" porting, three times as much porting as standard)
  • Middle porting (4 rows of 3 inch porting starting 6" into the barrel and ending 9" into the barrel)

The SQB barrels has more porting than any other barrel and the porting gets even heavier at the tip of the barrel, this also gives the lowest volume of any barrel tested, however before you say "see most porting = lowest volume" notice the middle porting is almost exactly the same as double porting, yet middle porting has 4 rows of 3" of porting, and double porting has 8 rows of 3" porting, exactly double the porting but yet with the same volume. This is because the further back in the barrel you go the higher the air pressure and the more air that gets blasted out the porting carrying sound with it, unfortunately very early porting also slashed efficiency. This test was done with much more data then sound that is just now shown for this particular test but I will mention that Unported and Standard ported barrels were more efficiency then the rest (you can view the entire dataset here)

more porting can help but it has to be laid out right for best results, it may give the same results to have lots at the tip as a little in the middle, but the lots at the tip will not cause you to lose out on other performance such as efficiency, however if low volume if all you want, then porting everyone at the expense of Efficiency will win the day.

This is actually a much smaller version of a test done in summer of 2009 that was used originally to help us in the development of Gen2 porting which was developed with the intent to lower volume while increasing efficiency and consistency, you can read more about Gen2 porting in the articles section of the site.

Data below


2) Bore size

Yes, even bore size can affect the volume of your marker, this is quite simple compared to porting however and quite linear, smaller bore size = louder and larger bore size = quieter. in the short test below we re-chronoed the marker to try and keep FPS close, notice the .687 was louder then the .685 (only by 0.02 which is so far within the margin of error its ridiculous) but also note that it shot 7 FPS hotter which accounts for increased Volume, between .681 and .693 the difference is 12DB which is substantial (and the .693 was also shooting 10FPS hotter (apparently we did a poor job of re-chronoing between each barrel or results would have been even more noticeable then they are) testing was done with 9" control bores.

Data below

 

3) FPS

this is very simple and most people already know this, the higher you chrono your marker the more air it will use and the louder it will be. We did not even bother with test data for this

 

4) Barrel Length

Barrel length has a small affect on volume, in many cases longer barrels are quieter but the main reason for this is because longer barrels have more porting, here is a small excerpt from a test with 6" 9" and 12" barrels, all 3 have the exact same porting, just as many holes in the 6" as the 9" as the 12". All markers were chronoed to 270 FPS +-5

As you can see the 6" has the exact same volume with or without porting, this barrel is simply too short for porting to have any effect, the 9" and 12" do however show a noticeable difference with porting vs without. The 9"ported is quieter than the 12" ported, however the 12" unported is not as loud as the 9" Unported but is louder than the 6" unported. this shows that for maximum volume you want a barrel closer to 9" long, when using porting, in this test 9" is most effective, but this is only using 4 rows of 3" porting, if you are using more porting a longer barrel will function better, but with minimal porting a barrel around 9" is optimal.

Data below

 

 

5) Barrel tips

Barrel tips can also have some effect on the volume of a marker, in some cases they can help spread out the volume more effectively (like porting) and in some cases they can amplify it (like a Cannoniser) Here is a chart to show the difference between just a few of the Flasc tips currently available

Data Below

 

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