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Gun Docc
09-09-2002, 06:06 AM
Howdy folks,

here is some very interesting info where i done some testing several years ago while playing with my chronograph on the differences between Feathers and Vanes when shooting them off the same bow

the reason i done this was to learn the differences between Feathers and Vanes as far as Velocity and Kinetic energy was concerned
i shot 5 arrows through the chronograph screens at each distance to get the average velocity for each which i could then figure the kinetic energy from

bow used:
Martin Firecat with 65 % letoff flight wheels and a draw length of 31 inches set to 80 lbs. of pull, also used an 18 strand fast flight string on the bow

conditions:
warm with temps in the 70's and clear, elevation around 1,000 ft. above sea level

chronograph used:
Oehler 33 with two foot spacing on the sky screens

arrows used:
60/80 Beman Hunter Carbon fletched with either 4 inch left hand helical Feathers or 4 1/8 inch left hand helical Flex Fletch Vanes using standard point adapters and 100 grain field points
the only major difference between the two arrows was the fact that the feathered arrow was 19 grains lighter than the vaned arrow all other aspects of the arrow were the same
feathered arrow weight 384 grains
vaned arrow weight 403 grains

speed at the bow:
feathered arrow at 384 grains 288 fps
vaned arrow at 403 grains 280 fps
kinetic energy produced Feathers 70.74 ft. lbs.
kinetic energy produced Vanes 70.17 ft. lbs.

speed at the 20 yards:
feathered arrow at 384 grains 264 fps
vaned arrow at 403 grains 270 fps
kinetic energy produced Feathers 59.44 ft. lbs.
kinetic energy produced Vanes 65.25 ft. lbs.

speed at the 30 yards:
feathered arrow at 384 grains 256 fps
vaned arrow at 403 grains 265 fps
kinetic energy produced Feathers 55.89 ft. lbs.
kinetic energy produced Vanes 62.85 ft. lbs.

velocity loss for feathered arrow:
20 yards 24fps
30 yards 32fps
velocity loss for vaned arrow:
20 yards 10 fps
30 yards 15 fps

kinetic energy loss for feathered arrow:
20 yards 11.3 ft.lbs.
30 yards 14.85 ft.lbs.
kinetic energy loss for vaned arrow:
20 yards 4.92 ft.lbs.
30 yards 7.32 ft.lbs.

doing a percentage on the kinetic energy loss at 30 yards it showed that there was a 21% loss of energy for the feathered arrow and only a 10.5% loss for the vaned arrow

this showed me a pretty significant difference between the two variants of arrows with only changing the fletchings
i no longer own the particular bow that i done all the testing with but it was a proven setup on game

i made the switch to the vanes after many years of shooting feathers and haven't looked back

nowadays i shoot basically the same arrow setup with the Flex Fletch vanes but I'm shooting a newer bow, a Martin Scepter II which is a good bit faster than the older Firecat was


i guess you could say this falls under the ''the more you know'' category....hehehe

good luck this season,

shadow
09-09-2002, 06:42 AM
WOW never thought a feather ~vs~ vien fletching would make that much diff. Thanks makes for interesting reading.

Arthur P
09-09-2002, 06:56 AM
Interesting results. Screaming arrow speeds for those days, for sure! Never knew the ol&#39; Firecat could get pumped up that tight. http://www.jesseshunting.com/forums/style_emoticons/<#EMO_DIR#>/smiley-biggrin-aqua.gif

It&#39;s amazing that the feather arrow lost 24 fps in the first 20 yards but only 8 fps between 20 and 30. Obviously, speed loss wasn&#39;t linear. The slower the arrow went, the easier it retained it&#39;s speed and energy. The vaned arrow lost 10 fps in the first 20 and 5 fps between 20-30. That IS linear, 5 fps per 10 yards.

I must ponder this info for a spell....

jayber
09-09-2002, 02:04 PM
Very interesting results indeed.......Might have to give the Flex Fletch vanes a go!