Serving... as in to tie in a drop away rest? I can't say yes or no, but I do know that I've chrono'd both before and after tying something in and there was no affect on speed whatsoever.
yeh serving my string for the drop away.. I don't know, I lost 5 fps from Sept to now and Im not really concerned I just don't know why.. the bow is shooting well, and I don't care to change it, I would still like to know why I lost it though.. the only thing added was serving inside the D loop top and bottom to prevent pinch, reckon that could have done it?? Not a big deal.. could be the electronic caliber at Gander was off?? I had it checked using the old calibers non eletronic and it said I was shooting about 72 lbs then I was at Gander and saw they had the electronic scale and tried it, said I was pulling 75n lbs...
Well it was maxed out back in Sept. and at Gander mt the scale read 75 lbs !! the shop I bought it from said 72 lbs. I was like damn, take it down to 70. so they took it out a whole turn and it read 71 lbs, so I stuck with it. But
Landon, so you've gained 3-4 lbs in your draw weight but have lost some arrow speed? You haven't added twists to the cables or strings? Thinking aloud but I've always heard serving a dropaway into your cable will throw your bow out of time. Maybe something has happened there. Maybe the scale is off?
No I didn't gain any weight in draw, it is set at 72 lbs. I just lost 5 fps after I had a new D loop installed with some serving insde the D loop to prevent pinch...it says that for every 3 gr you add to the string, you lose 1 fps. I seriously doubt I have that much serving on it...who knows, the chrono could be off..?? Im concerned too much about it, it still flies great.
I have had 3 fps difference between the exact same arrows and quite possibly the same arrow. The best way to get the speed is to shoot a bunch of arrows throught the chrono then get the average. If you want to check speed at a later date, do the same, a bunch of arrows then the average. Just shooting one or two or a few and then sweating a 5 fps difference is probably giving it too much credence :d .
I didn't think of it Bruce. Thanks, I knew when you chimed in I needed to listen, I said to myself " self, if Bruce is responding then pay attention." As always, you put it in perpsective.
I was gonna say maybe your cable/string has stretched and caused you to lose draw weight/speed but that dont seem to be the situation! I bring this up because I had the bow shop crank my limbs down today on a 70lb max draw bow and it was only pulling 62lbs!!!!! I have put off getting a new cable for the past two years, he said that the drop probably came from the cable being stretched so bad? I hope I can gain a few lbs with a new cable!!
I would guess that you are looking at a normal variance in chrono error. Possibly coupled with slight string stretch, different temps etc.
When checking the velocity of projectiles fired from firearms, an average is calculated because of variances in overhead lighting (projectile reflectivity and shadow casting ability) and subtle electronic imperfections within the chrono’s circuitry. Often the chronograph has an averaging program built directly into the unit for comparison of shot strings. Barometric pressure and relative humidity also effect projectile velocities. Changes in the distance of the point of your arrow to the first chronograph screen will also produce variances in displayed results. I have found that extreme low temperatures also effect arrow spine and limb stiffness (i.e. draw weight) slightly. I believe that rapid fire shooting also warms limbs and will affect speed/point of impact (flexural heat build up). If you are sitting in your stand waiting for Mr. Right to saunter along, your bow limbs will probably be cold (just like the barrel of a hunting rifle). Those are the conditions I try to simulate by slow fire practice. This new breed of chronographs is much more accurate than ever before. Brucelanthier was right, spend the time to get at least a few, slow, shot string averages and then compare them to another day’s attempt. At 50 yards, the 5fps will make a difference of maybe an inch in drop. At 20 yards, in a hunting application, the 5fps won’t show at all. Remember the point of aiming for the center of the vital zone. A good arrow head will still do the job one inch in any direction. I would be more concerned with consistent grouping than with the chrono’s display.
