More Physics
In a post over in the EDgun area, Awny explained the relationship between muzzle velocity and pellet mass under the assumption that the muzzle energy remains the constant even when the pellet mass changes.
http://talonairgun.com/forum/viewtopic.php?f=34&t=30761#p310480
Here’s a spreadsheet that makes a similar kind of simplifying assumption to estimate a few other interesting numbers. The simplifying assumption here is that the pellet is accelerated by a constant force. (This is also called “uniformly accelerated motion.”)
So the headline reads like this:
“Pellet Accelerates to 900 ft/sec in 18 inches – 22 pound force implicated in the acceleration”
Pretty exciting, eh?
-x356b
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Viewing 9 replies - 1 through 9 (of 9 total)
So your predicting hoot will miss the chickens no matter which pellet he ends up putting in his new lelya??
Personally I hated physics at school.. all the hot girls were in the art classes so that’s where I spent my time..
Here, let me dumb it all down for you with a flow diagram.. 
Very nice details of the various metrics X356b. Thanks.
The numbers demonstrate interesting facts such as the how small the rotational part of the energy is compared to the translational (though rotational momentum is crucial for pellet stability). Another interesting number is the effective bar behind the pellet (neglecting friction of course).
Awny
Sharpshot,
My background is in engineering, which involves a lot of physics. I’ve done a fair amount of work on engines and engine combustion. Gas guns have a lot of similarities to piston engines, and one big difference. A gas gun throws away the piston on every power stroke.
-x356b
Thanks x356b. Some people just don’t appreciate the mechanics of it all. Seems like you have it figured out. Do you have a degree in physics like awny too??
Sharpshot,
Damn, you’re handing me this great straight line about “free bodies” and I’ve got nothing. Must be too late.
Anyhow, a free body diagram of the pellet in the barrel has a big push on one side and some small retarding forces on the other. Accelerating force from air pressure behind the pellet pushes the pellet out of the barrel. Rifling causes the pellet to spin. The pellet gains linear and angular velocity. Retarding forces slow all of this down. There’s friction between pellet and barrel and there’s aerodynamic resistance on the pellet front side.
Once the pellet is out of the barrel, it’s a different story. Aerodynamic forces on the pellet are complex. Lots of wacky stuff can happen. Have a look at the spiraling pellet videos from Altaros.
-x356b
Can you draw the free-body diagram equation for me??
Mind numbingly! Lol
Jk I know what all that mean..
Viewing 9 replies - 1 through 9 (of 9 total)
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I think the key to Unckie Hoot hitting the chicken lies in getting the right color pellet. The green (longer wavelength) pellet falls short and the blue (shorter wavelength) goes long, so Hoot needs a bluish-green pellet somewhere in the middle.
I wonder if he had a brown pellet, where would it land?
-x356b