What number is "Close enough" for the speed of sou
I googled it and it varies. I saw numbers as low as 1085 all the way to 1126 Fps. So my question to you all is…. how close is TOO CLOSE when setting up for max velocity? I know alot of people use 1000 Fps. I know Walt uses 925 in Hawaii. I am guessing here (help me out Walt) but I think I can get closer to 1000 in the summer where I live (10% humidity and 90-100 degrees) If I use 1126 as my number, is 1000 still too close? Where is the “Trans-sonic barrier”?
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At 55 F 1112fps Warmer than 55 means faster annnnd colder is slower.
A frequent question is “What is the speed of sound?” The reply should be “At what temperature?”
http://www.sengpielaudio.com/SpeedOfSoundPressure.pdf
If you look closely at the formulas you will see that the speed of sound is dependent primarily on temperature for any given gas. In this case since we are talking about air it is the temp of the air that make the speed of sound vary far more than the density as a result of humidity.
Forget the air pressure, but look accurately at the very important temperature.
Speed of sound – temperature matters, not air pressure
Notice: The speed of sound changes clearly with temperature,a little bit with humidity − but not with air pressure (atmospheric pressure).
The temperature indication, however, is absolutely necessary.
Thanks Syn., A.M., Pab. Slayer I didn’t get it? But I think a lot go for 900-950. I’m going to have to try to do the chrony AND target shoot at the same time. I do a lot of my shooting at what some consider the upper limit for a pellet gun. That’s why I wanted to get as close to 1000 at the muzzle as possible IF again IF accuaracy is still there.
is what I shoot for
A very humid day brings the speed down I think. I’ve had them crack at as low as 1050 before.
Probably decrease, air is less dense at higher elevations…
I shoot .25 kodiaks about 1050fps.
Does the SOS increase or decrease with higher elevation?
1050…
SOS is 1129fps at 70ºF at sea level…
…Good answer. The obvious slipped past us all save for you.
LOL. I love it Mike. Perfectly worded with VERY few words. Is it safe to ASSume most people have their accuracy falling off at 1000 Fps. ???
…Good answer. The obvious slipped past us all save for you.
When accuracy starts falling off, your too close!!! 😉
Well I was telling my buddy about the Combro and we got to talking about how he should be able to start at 3K and max pre-load, then slowly back it down as it peaks then ramp it back up as it starts to fall off. We were wondering how close is too close. I guessed 1000 is as close as he should get.
I stay well below at around 870-920fps. I have shot my best groups shootings JSBs at 880fps and also measured the highest bc for 15.9g JSBs.
What are you trying to accomplish…. that would be the first question, I guess.
If you have a Condor running at 850fps with Kodiaks and one running at 950fps… are you really going to notice a difference in performance…especially on game?
I certainly dont profess to be a numbers guru, but at my elevation, I tend to try to keep things at around the 1000fps mark or under. Sure, it’s nice to pop one off higher just for bragging rights, but aside from that…. nah….
I guess if you really wanted to know, keep firing until you hear the sonic CRACK and then you’ll know…..
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Here’s a link to the online calculator
http://www.sengpielaudio.com/calculator-speedsound.htm