Two air rifles with the same fpe compared.

MACTEN

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Nov 18, 2020
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I actually just mean the Db level as I still haven't put them to the range test.

The Kozak with a much thinner shroud is about 84.2 Db and the Vixen 85.4. This was a measurement taken at 1 foot lateral to the muzzles. So I measured pretty close and indoors without pellets being fired, which isn't ideal. I just wanted a baseline with the same variables. What's weird is the obvious shroud differences. Neither one is loud at all mind you, but it struck me as strange that the Vixen wasn't quieter than the quiet Kozak. Has anyone else noticed the Vixen is a bit louder that it looks like it should be?
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i have not thought hard about this, but off the top of my head i am guessing the extra volume doesn't matter that much unless there is a pellet (or slug) in front of the air charge to stop it from being immediately expelled.

without the projectile, i think you're just pushing out the air that is already in the either one, along with the air from the shot.

it is also possible one gun is using more air to achieve the same velocity or level of energy.
 
The big shroud on the Vixen are pretty much just for optics, and it do look cool, i just wish it was able to hold high pressure air too, just imagine how many shots you could get from a fill then.

At least i would prefer that and then have a barrel ending in nothing unless you screw something onto it.

I would like to see a Vixen with a fat boy on it.

My Vulcan 3 do have about 100 mm or so of dampener build in, and it is also fairly quiet, but i am in the market for something to screw on the end that are the same OD as the shroud ( 38 mm )
 
i have not thought hard about this, but off the top of my head i am guessing the extra volume doesn't matter that much unless there is a pellet (or slug) in front of the air charge to stop it from being immediately expelled.

without the projectile, i think you're just pushing out the air that is already in the either one, along with the air from the shot.

it is also possible one gun is using more air to achieve the same velocity or level of energy.

That might be it. I need to do more shot strings with it for sure.
 
The big shroud on the Vixen are pretty much just for optics, and it do look cool, i just wish it was able to hold high pressure air too, just imagine how many shots you could get from a fill then.

At least i would prefer that and then have a barrel ending in nothing unless you screw something onto it.

I would like to see a Vixen with a fat boy on it.

My Vulcan 3 do have about 100 mm or so of dampener build in, and it is also fairly quiet, but i am in the market for something to screw on the end that are the same OD as the shroud ( 38 mm )

The Vixen is a 300 Bar rifle. Honestly it's still very quiet even without a pellet at 84+ Db. (EDIT 85+ Db) I just though it was strange that it wasn't as quiet as the Kozak with a very thin shroud. 
 
I have noticed that tuning has a noticeable impact on sound. If you have a well balanced tune that's using 95-97% of the available HST at a given reg set point, it tends to be quieter. At least that's my perception, could be more the signature of the sound than actual dB level.

Not sure at this point how efficient it is. I can't really tell much difference in volume with my ear, just the type of sound. The Vixen has a slightly sharper report. The Db meter showed it was about 1 Db louder than the Kozak which is the actual Db level.
 
I have an Uragan, I believe the vixen has a similar shroud, the Uragan has an all metal fixed one piece baffle in the shroud with no Dampening material such as Felt, it is quiet, but louder than most of my other shrouded guns that have separated plastic Baffles or plastic Baffles and Felt (most quiet), I don't think being plastic baffles or metal baffles make a difference, but being fixed with no felt or Dampening material does make a difference, I've experimented with Baffles, I've found the fixed one piece baffles with no felt wrapped around is louder than with felt wrapped around, also louder than non fixed separate baffles with no felt, of course baffle design makes a difference, air stripping efficiency and sound absorbing materials are key to making a gun quieter.
 
I have an Uragan, I believe the vixen has a similar shroud, the Uragan has an all metal fixed one piece baffle in the shroud with no Dampening material such as Felt, it is quiet, but louder than most of my other shrouded guns that have separated plastic Baffles or plastic Baffles and Felt (most quiet), I don't think being plastic baffles or metal baffles make a difference, but being fixed with no felt or Dampening material does make a difference, I've experimented with Baffles, I've found the fixed one piece baffles with no felt wrapped around is louder than with felt wrapped around, also louder than non fixed separate baffles with no felt, of course baffle design makes a difference, air stripping efficiency and sound absorbing materials are key to making a gun quieter.

The vixen has a one piece baffle with felt wrapped around it. It appears to be aluminum and well made. The felt is very thick but not sure it matters with this design.
 
I have noticed that tuning has a noticeable impact on sound. If you have a well balanced tune that's using 95-97% of the available HST at a given reg set point, it tends to be quieter. At least that's my perception, could be more the signature of the sound than actual dB level.

Not sure at this point how efficient it is. I can't really tell much difference in volume with my ear, just the type of sound. The Vixen has a slightly sharper report. The Db meter showed it was about 1 Db louder than the Kozak which is the actual Db level.

I'm not an expert, but I believe, if you want to compare the two rifles for sound volume and tone, they should have as close to possible identical tunes. 
 
I have noticed that tuning has a noticeable impact on sound. If you have a well balanced tune that's using 95-97% of the available HST at a given reg set point, it tends to be quieter. At least that's my perception, could be more the signature of the sound than actual dB level.

Not sure at this point how efficient it is. I can't really tell much difference in volume with my ear, just the type of sound. The Vixen has a slightly sharper report. The Db meter showed it was about 1 Db louder than the Kozak which is the actual Db level.

I'm not an expert, but I believe, if you want to compare the two rifles for sound volume and tone, they should have as close to possible identical tunes.

+1, most of my guns of the same caliber are similar in power, tuned about the same.