Shooting a pellet faster means a flatter trajectory, but is there a limit where the same pellet does not fly true if it is pushed at higher velocities? If the projectile is sent on its path at such a high speed is there benefit or a point when the rate of twist (rifling) should be changed? Or a change in the projectile weight?
Just curious of the physics. Thanks.
Beats the heck out of me. ;D. Actually that's a good question,not smart enough here to answer you though. All I do is load and shoot.
Daisy 953s have a one in fifteen twist to help them be accurate at lower velocity for 10 meter shots. I think most pellet rifles fall between 1/16 and 1/18 not sure though...
Here is some reading
http://www.pyramydair.com/blog/tag/twist-rate/ (http://www.pyramydair.com/blog/tag/twist-rate/)
Aren't most lothar airgun barrels 1 in 12 ? Like I said earlier this is way beyond me, I need a drink now. ;D
Quote from: bgmcgee on October 22, 2013, 02:37:16 AM
Aren't most lothar airgun barrels 1 in 12 ? Like I said earlier this is way beyond me, I need a drink now. ;D
:-* :-* :-* :-*
First, diabolo pellets are designed for subsonic flight and should stay below about 900 fps or the Cd starts to go parabolic when getting close to Mach-1
Second, too much spin can cause two problems:
- overstabilization, the strong gyro effect keeps the pellet pointed slightly upward while the pellet is on a downward arc and leads to precession
- Magnus effect, or spin drift increases with the rpm's and can be noticed at longer distances
Twist rates....not sure but 1:17 is in the ballpark
Wyo is correct, most pellets don'y fly well over 950fps. Keep everything sub sonic is best between 850-950 fps range for the best accuracy.
Glen
Quote from: bgmcgee on October 22, 2013, 02:37:16 AM
Aren't most lothar airgun barrels 1 in 12 ? Like I said earlier this is way beyond me, I need a drink now. ;D
I think Lothar Wather barrels are 1 in 17.7 the 753 and 853 have the L.W. barrel, the 953 has a daisy barrel.
more reading
http://www.gatewaytoairguns.org/GTA/index.php?topic=33650.0 (http://www.gatewaytoairguns.org/GTA/index.php?topic=33650.0)
Anyone know what a stock Crosman barrel is?
I have heard 1 in 16 but do not actually know...
Hey, where is my drink ;)
Quote from: K.O. on October 22, 2013, 04:09:24 AM
I have heard 1 in 16 but do not actually know...
Hey, where is my drink ;)
Oops sorry I drank it. ;D ;D ;D
After reading what Wyo posted I really need one.
My brain still hurts :-[ I almost didn't ask but... It'll take some time to digest this info. And to finish my drink. Thanks -- truthfully very interesting.