 |  | | | |  | |  |  | 2031 fps on Air ! - Now 2162 fps ! |  | |  |  | |
 Posted: Tue Mar 22, 2016 8:55 am |
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| rsterne |
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| Joined: 15 Jan 2008 |
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| Location: Coalmont, BC |
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Lloyd Sikes at the AirGunLab has broken 2000 fps in his first attempt.... The barrel is a .278 cal smoothbore (piece of DOM tubing), 47.5" long, powered by a 55 cc reservoir with a unique pellet release mechanism that allows full pressure against the pellet before firing.... The 9.1 gr. pellet was made from aluminum, sealed into the bore with an O-ring, and this test was done at 4000 psi....
https://www.youtube.com/watch?v=JWt5DnfYH3I&feature=player_embedded
This permanently puts to rest the idea that 1650 fps (the molecular velocity of air) is the limit for a PCP.... Congratulation, Lloyd, on a job well done....
Bob |
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Last edited by rsterne on Thu Mar 31, 2016 10:41 am; edited 1 time in total
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Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal: Too many to count! |
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| Posted: Tue Mar 22, 2016 9:02 am |
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| Slavia |
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| Location: Waseca, Minnesota, USA |
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Sounds like the "unique pellet release mechanism" is the key. Maybe more acceleration at the start, without having to rely on a viscous fluid chasing the bullet down the bore.
Just out of curiosity, how does the "molecular velocity" of expanding nitrocellulose combustion gases compare to air? |
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 ¡Listo! ¡Apunte! ¡Fuego! |
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| Posted: Tue Mar 22, 2016 9:08 am |
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| rsterne |
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| Location: Coalmont, BC |
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Way faster, because of the high temperature....
Bob |
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_________________
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal: Too many to count! |
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| Posted: Tue Mar 22, 2016 3:31 pm |
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| Bob La Londe |
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| Joined: 05 Nov 2014 |
| Posts: 146 |
| Location: Yuma, Az |
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| I suppose I need to grill my UPS guy next time he stops by. He claims one of my neighbors (country neighbors, not city neighbors) is working on a small bore pneumatic cannon for the military. It would be interesting to meet him and find out what kind of velocities he is getting. |
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| Posted: Thu Mar 31, 2016 10:40 am |
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| rsterne |
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| Joined: 15 Jan 2008 |
| Posts: 2998 |
| Location: Coalmont, BC |
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Lloyd has upped the bar again.... 2162 fps with a 7.7 gr. 0.278" cal. projectile at 4600 psi in a 46" barrel....
Bob |
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_________________
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal: Too many to count! |
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