Cossack

Yesterday afternoon, while shooting in 88 degrees, my bow was right on. This morning, at 64 degrees, it was shooting nearly 2" lower at 20 yards, & at 30 yards so much lower that it would have cost me a kill. It took 6 clicks to bring it back on at 20 yards. I had noticed previously that the bow shot a bit lower when the humidity was high but this, as they say, is a whole new ballgame.

Buckhunter46755

I don't know a lot about bows yet, but that is interesting. I could see how that could maybe happen though. But you'd think there would have to be more of an extremetemp. difference. Maybe the wax in the string being stiffer has something to do with it. (just a wild guess) Butthen again you'd think lower temp. would = less friction, meaning faster speed andhitting higher.I'll be looking forward to what other's think. That's definately something I'm going to check out. Like you said, if it could cause someone to not make a kill shot then it's something to consider.....
but what do I know...lol

chris

Pydpiper

Temperature fluctuations will cause tiny variables in POI, but not 2".
Check that your brace height didn't change, the heat will undoubtedly allow the string to stretch.
Also, may want to check your scope screws, I had two bad Vari-zones before I switched to the Lumi-Zone, and no further problems.

smokepolehall

The only way i can relate to that is. When ihunt high altitude out west my arrows hit higher. Air is good bit thinner and less resistance.

Planter

Something just doesn't sound right. Cossack apparently knows his stuff but to be off that much with such a small degree of overall temp change would seem to be a GIANT problem in the real huntin world. Figure it out Cossack cause I sure can't and would really like to know.
Maybe cause you have so many bows you just picked up a different one the second time?

Dnk

When David was at my cottage he let his bow in its case in realatively high heat (nothing crazy) for a bit and the POI was lower the next day. I think Pydpiper should tell the whole story to be better understood.

Pydpiper

I break down my crossbow into a compound case for travel, it works terrific and holds all my goodies.. I set the case on the back deck in the shade to participate in some other cottage related festivities.. The sun passed over the case in the afternoon..
Next day I brought out my bow and the brace height dropped over one inch, the wax from the string was oozing from between the fibers.
I simply readjusted my brace height to the 1 1/8" that has always worked so well for me. Not paying much attention to my accuracy I shot for another day.
Once I got home I set up on my 20 yard bench, and much to my dismay I was shooting 2" low.. Brace height was good, arrows were good.. Something happened in the bow case that day that cost me 2"..
I should have stuck to the compound that day, but that turned out to be a bit of a headache too..

KLS

did you ever figure out exactly what was causing it?







I've never noticed it in my shooting, nor ever really considered it, but that humidity or"heavyair" concept is kind of interesting, I guess by itself I dont really see it causing a 2" drop at 20 yards either, but I can see where it could be entirely possible to have an effect, especially with using feathers

not that it has anything to do with this but I've often wondered if condensation forms inside arrows during temperature changes

Cossack

Our temp hit 94 during yesterday and it was hotter in the garage where it was kept. I noticed that the brace was a tad lower this AM, that could be it. It was a "settled" string but for some reason it sagged just a tad. I did re tighten the screws that hold the bow to the stock last night as I checked them prior to shooting. But it shot to the same POI when I finished. This one definitely has me stumped. Only thing I can figure is that since I had waxed the serving before putting it away, and it got some 40 degrees cooler during the night, could be due to increased drag from stiffer wax (?) Shot it tonight (it didn't hit much over 75 degrees today) and it still shot to the same POI...and right on clear out to 50 yards. One thing is sure, no more waxing after hunting starts.

Pydpiper

If your string creeps your POI would rise due to the increased power stroke.

I don't know exactly what happened in my situation, part of me wants to think I weakened the limbs with excessive heat, but it seems too uniform. I will get the Chrony out one day to see if there was a velocity loss. I now have a suspicion I did damage to my string and that somehow may be responsible.