HotLZ

I've been shooting my new OG for a couple days now, and decided to run it through the chrony. My specs are 31" draw, 60 lbs, 412 gr. acc 3/60. The chrony read 272 and 273. The BC said 314 with a 300 gr. arrow. I just can't see dropping 41 fps for 112 grains. Does that seem right?

Also, the 31" draw was not at 80%, but about 3/4 of the way towards the short setting, so to get 80%, the draw length wound up being closer to 31.5 than 31.

buckeye

Going by the rule of thumb 10fps for every 30 grains takes you from 314fps to 277fps.

Add on what ever else you added to the string like a peep and or a kisser. Sounds just about right on[8D]

HotLZ

I thought the rule of thumb was more like 1 fps for every 5 grains, not three. Also, I thought the binary cams were really supposed to like the heavier arrows and be more efficient with them.

buckeye

Taken from BowTechs 2005 manual. Refering to the EQ cams.


"Every 3 grains of added arrow weight results in approximately 1 fps speed loss."

You could also shoot through another chrono just to compair the speeds.

HotLZ

Thanks buckeyebuckhntr. I've read through the manual online several times and I forgot that it said that in there.

walks with a gimp

HotLZ, My Allegiance shot a 356.2 grain arrow 297 fps and a 484 grain arrow 257 fps while set on 60 pounds and 29 inch draw. That's a 40 fps loss with a 127.8 grain difference in arrow weight. Pretty close to what you've seen

PABowhntr

Once you start getting below 6 grains per pound of arrow weight I have found that the ratio changes considerably. Above 6.5 grains per pound the 1 fps for every 5 grains normally holds true but below it and you start running into a ratio more like 1 fps for every 2 or 3 grains per pound.

On another note, now I am really ticked since the 31 inch draw length Old Glory models appear to be available. [:@] However, what you listed about the draw length discrepancy might be why they have not showed up until now. I will be sure to check mine once it arrives.

muzzyman88

This brings up a question I have. I have been going through the numbers and variables with my setup and keep coming up with roughly 290ish. This is an Allegiance set at 65lbs, 28" with a 365gr arrow.

Does that sound about right? I was looking through the Bowtech manual and was kind of surprised to see that they figure only loosing about 3fps per 10lbs of draw weight. I thought is was more than that.

What is the usual figure for draw length? I was thinking along the lines of 10fps for every inch.

Double Creek

That's pretty good if you ask me.....

Bowshopper

Muzzyman 88 , I was told the 3fps / 10lb. of draw weight means at 5 grains /lb. IBO. ( Arrow @ 70 lbs would be 350 grains, @ 65lbs 325 grains etc). Not sure if you are seeing this way???
What do you think my OG will get at 27.5 draw/ 50lbs/ 300 grains?
Going on week 10 waiting on my bow. Geez I never thought it would take this long . I heard you could order the equalizer bows with heavy or light limbs. Not sure how anyone tells the difference. If its true I hope I get HEAVY 50's