Rate of twist

[twigboy]

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.

[bgmcgee]

Beats the heck out of me.  . Actually that's a good question,not smart enough here to answer you though.  All I do is load and shoot.

[K.O.]

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/

[bgmcgee]

Aren't most lothar airgun barrels 1 in 12 ? Like I said earlier this is way beyond me, I need a drink now. 

[mudduck48]

Aren't most lothar airgun barrels 1 in 12 ? Like I said earlier this is way beyond me, I need a drink now. 

[WyoMan]

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

[tinker]

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

[K.O.]

Aren't most lothar airgun barrels 1 in 12 ? Like I said earlier this is way beyond me, I need a drink now. 

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

[arkmaker †]

Anyone know what a stock Crosman barrel is?

[K.O.]

I have heard 1 in 16 but do not actually know...


Hey, where is my drink

[bgmcgee]

I have heard 1 in 16 but do not actually know...


Hey, where is my drink

Oops sorry I drank it.
After reading what Wyo posted I really need one.

[twigboy]

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.