I have recently tuned some carbons with 225gr. tip weight and 610gr. total weight for a 55#@28" recurve. I went to the archery shop and they chrono'd it at 175 fps. The last time I chrono'd it was with a lighter set up and it was about the same. My question is does the additional weight, up to a point, not effect arrow speed? I love the added force on impact with this weight and was pleasantly surprised that I didn't loose trajectory.
I would think that if a signifcant amount of weight is added to the arrow then that arrow would chrono slower. Since in your case you saw no difference in your chrono numbers then I would think that maybe the heavier arrow is better tuned for that bow. In other words maybe the lighter arrow was not tuned well for the bow and therefore the less than optimal flight would account for it not reaching a higher fps. I'm just spitballing here I'm sure some one with more experience playing with a chrono could explain better.
I have experimented with my chrono and varying arrow weights string weights, silencers-you name it. For me, weight and speed are completely interdependent-heavier is slower and lighter is faster, whether the weight is in the front or the back or even on the string, has not mattered.
The question is-how much slower or faster? Going a little heavier always made sense to me because the loss in speed was negligible compared to the gain in 'power' or 'potential penetration' you can give that any physics name you like.
As far as trajectory is concerned; at 20 yards I personally have not noticed much change.
Good to hear from you guys. The first arrows that I chrono'd had 150gr. tips. The new ones are 225gr. tips. There was about 2 fps difference. I really thought it would have been more.
75 grain difference should have slowed the arrow more, maybe 10 fps.......are you shooting by hand?
Yes, I shoot both arrows with a tab. I wanted to see how much the heavier arrows would drop. So, I shot out to 40yds. If I held the arrow tip 12" high of the bullseye it hit the center.
Same arrow different tips or two different spine arrows?
Same arrows just different tips. They are both CE250s. I think the lighter shafts are .5" longer though.
I am by no means a master at physics but it could have been with the lighter arrow you were not getting the maximum efficiency from your bow and with the heavier you are getting the max efficiency.
Only thing I can reason for the results.
I think the posters above hit it with a tuning problem. 75 grains of change should have affected the arrow more than you are seeing.
Glad you are pleased with the new setup. 610 grains moving at 175 fps should plow through anything with a sharp head up front.
I agree, the arrow with 225 up front was tuned perfectly and the one with 150 may of been close but not perfect. Also if you placed the chrono well down range the heavier arrow would be traveling faster as the weight carries its momentum better. Shawn
I dont no if this will shed any light on this or not.A few years ago i took a compound an made 2 arrows 1 300gr. and 1 400gr. Shot them threw the chro. at 3 feet the lighter arrow was 20 fps. faster. but at 40yds. they were the same speed.
That's what I was thinking Shawn.
If the bow was working more efficiently with the heavier arrows I wonder if the shooter could feel the difference in vibration/handshock that the lighter arrow would cause by not efficiently taking all the energy the bow put into it?