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AlienX
09-03-2009, 07:46 PM
hey guys just tryin to guess my arrow speed i shoot easton powerflights with blazer vanes 100 grain tips the weight is 392 grains. my bow is set at 66# draw length is about 28". nothing but a peepsight and a d loop on the string. o yeah im shooting a rytera alien x :) i hoping that i might be close to 300fps+/-. the sight says 329 with 28/60 and 300 grains. i know a chornograph is the best way but i was hopin someone would have an idea
thanx Alien X

bfisher
09-04-2009, 06:48 AM
Justan educated guess, but working from the advertised IBO??????

Subtract 10 fps for factory fudging. Now we're at 319fps. Subtract 30 fps for the extra arrow weight--now it's 289fps. Add 10 fps for the extra draw weight--- 299fps. Subtract 5fps for the stuff on the string----294fps. Now subtract 4fps just forgood measure and round down to 290fps

Anything over that is a bonus and may make you feel better. Now when you do chrono the bow let me know how close I was.

Spiker
09-04-2009, 09:13 AM
BFISHER - bet yer within about 3fps !

jmo...

Jake-the-snake
09-04-2009, 10:33 AM
i would say 285-290, my firecat is just like that and i get 289 out of it:)

Dave308
09-04-2009, 11:23 AM
This will get you as close as possible without a chrony.

http://utopiaprogramming.com/ke/KineticEnergy.html#

AlienX
09-04-2009, 12:00 PM
:D:Dthanks for the help guys:D:D

NewNYBowhunter
09-04-2009, 06:16 PM
I did a chronograph on my Firecat with 70# draw weight, 30" draw length 362 or 368 gr. arrow, Martin whisker biscuit, G5 meta peep, kisser button, and a string loop, and got 309 fps.
I have more than 1/8" between my cables and my posts, but not sure how to twist them properly, and then bring the ATA and brace height back into spec.
If I twist the cables to "wrap the cams" do I untwist the shooting string to get the Axle to Axle and brace height back? Or do I just deal with a shorter ATA?

NewNYBowhunter
09-04-2009, 06:44 PM
I just checked my ATA and it's at 32 9/16" my brace height is at 6 7/8" my tiller is even, and my center shot is about 7/8'' from the shelf. I have about 3/16'' distance from the edge of the pin to the cable on my lower cam, and just a hair more than 3/16'' on the top cam. How much speed can be gained from a small adjustment to bring me in by about 1/16'' on the cams each? And approximately how many twists would it take to make up how much space?

AlienX
09-26-2009, 06:06 PM
:Dwell i just got my bow chronoed at 320 fps with a 309g arrow:cool: what i normally shoot isa392 gr arrow at 293 fps :D I LOVE THIS BOW

Montalaar
09-27-2009, 12:37 PM
309gr Arrow at 70 lbs?

You know that this will void your warranty?

jpermenter
09-27-2009, 02:07 PM
Bfisher was all over it, would have been closer without the 4 for good measure subtraction!.