Chronograph

[wabow]

I'm in the market for a chronograph and found this bow mounted unit. Anyone use one or heard good or bad.

http://www.keystonecountrystore.com/Chronographs_-_Paper_Tuning.html

Don

[Todd_ID]

Probably works good for bows, but why not spend the same amount and get one you can use for everything?  I have the ProChrono $99 Cabela's special, and I just put it on a block of wood or on the stove in my shop.  I don't worry about the tripod, and I've never installed the wires and diffuser hoods; I just shoot somewhere over the top of it and go. 

[carpsniperg2]

yeah i have used them one of my friends has one but i don't think it is as great as unit as the shoot threw models myself

[whacker1]

The diffuser hoods will be needed some times for rifle and pistol times if the sun is directly over head.  I have never fired my bow over the chrono, but intend to in the next few months.  

Chrono's also go on tripods really well if you have one for your spotting scope.

[wabow]

Thanks, I really dont have the need to chrono anything but the bow, not really a "need" for that either. I'll just grabbed the cheap one at cabela's and set it on my camera tripod, works fine.

Don

[wabow]

But since we a discussing chrono's. Is it normal for a bow to shoot under IBO when all conditions are the same as IBO? Are the number usually inflated by manufacturers?

Don

[carpsniperg2]

most of the time ibo is best numbers 10 shots may be 300 and one or two hit 310 and that seems to be the rating they get  but my x force was very close to ibo when i set it up ibo style it was off my 4 fps if i remember right. so yes 70lbs 350grain arrow etc most the time it will be a bit slower i am sure i remember right just a rest and the arrow no nock point/acc etc so yes it is most the time going to be a little lower then the ibo rating on the bow

[Todd_ID]

I've yet to see any manufacturer that doesn't inflate their numbers by a few.  Like he said above, they shoot and tweak, shoot and tweak, shoot and tweak, shoot and tweak and take the highest number they can get to advertise with.  Some are worse than others; generally Hoyt has proven to be the closest over my chrono, but they are still 1-4fps inflated.  Mathews seems to be the highest inflation at around 5-8 fps.  You have to really tweak a bow to get the number they advertise.  Once you get the right combination of limb torque, rest tension, string length, etc., then you might get the factory number, but you won't have a bow that shoots worth a darn.  The main way they can inflate the number is in the draw length tolerances since the IBO rating doesn't have any tolerance factor specified like the AMO number does.  If you chrono a bow that has a 30.25" draw length and then call it an IBO number that should have been done at 30", then that's inflation in my book.

[whacker1]

maybe you need to go up in elevation to have less air resistance? 

Maybe at 10,000 feet you can make up that 1 -10 fps? 

[coachcw]

maybe an ibo question . I've found many bows really fall off with a hunting arrow . If your worried about speed shoot the hunting combos through the chrono before you buy a bow you might be a lillte dissapointed. I've found the cam and a halfs to maintain speed well with the heavier arrows.

[Drifterat]

Ambient temp can also have an effect on bow speed. Colder temps = stiffer limbs = faster speed... I read somewhere that PSE puts their bows in the freezer before they shoot for IBO speed...