Understanding IBO

[Geewhiz]

This post is just for me to vent my annoyance with the (lack of) tech advances in modern compound archery/exaggerated IBO claims.

I have been shooting a 2013 mathews zxt since 2014. I've enjoyed my time with it and had a good amount of success with it. For the last few years I have been casually bow shopping here and there but have been so unimpressed with the specs of the new high dollar flagship bows as compared to my now 12 year old bow. Recently, I reluctantly purchased a 2024 model Mathews lift, mainly I think just because I wanted a newer bow and my friend bought one.

I realize there are many factors that make a good bow a good bow but the 2 factors that seam most important to me from a practical standpoint (and someone who does not do my own tuning) are the physical weight of the bow and the speed it will fling an arrow. Admittedly, I don't nerd out on my setup, I just want something that will work for the task at hand. My 2013 bow weighs 4.3 lbs and IBO is 326. This lift weighs 4 lbs and IBO is 340.

I got it set up and tuned and decided to shoot the same arrow out of both bows through a chrono just out of curiosity. My 2013 bow was set at 70 lbs with a 30 inch draw. My 2024 bow is set at 75 lbs with a 30 inch draw. My old bow shot a 535 grain arrow an average of 269 fps. My new bow shot the same arrow at 278 fps. So 5 lbs heavier draw and 11 years in tech advances and "superior and vastly more efficient materials" gave me a net gain of about 9 fps. Seams disappointing and practically unnoticeable.



Yes I realize speed isn't everything.



My new bow shoots a 435 grain arrow at 303fps.

I looked up IBO ratings and supposedly IBO is measured with an 80 lb bow with a 30 inch draw shooting a 400 grain arrow. So theoretically If I bump up my draw weight by 5 lbs and nock off 35 grains of arrow weight it will increase my velocity by 37 fps? Doubt it.

Seams like they have really just maxed out the materials that are currently available?





That is all.

Thanks for reading my rant.

 

[180ls1]

100% agreed lying about speed is shameful.

That said, old bows have prioritized speed due to lack of range finding an movable sights. Most of the improvement the last couple of decades are with shoot-ability where they have made significant strides. If you just prioritize speed you're bound to be disappointed.

 

[Beendare]

Well yeah....many guys look at the stats as part of their purchasing process.

Those of us that have been shooting compounds for decades are less impressed with pure stats...and more interested in how the bow shoots and feels.

Real world; A few FPS doesn't matter much.

 

[Mighty Mouse]

That Lift speed does seem a bit slow. Did you measure draw weight? Having 75# mods on the bow doesn’t guarantee it’s actually making 75#.

 

[Geewhiz]

I did not measure the draw weight but I did ask to confirm what the poundage was set at when I picked it up. My buddy who bought a lift x this year is shooting arrows of near identical weight with a 29" draw and 70 lbs and he said his chrono'd at the exact same velocity as mine.

 

[Mish-pop]

This just confirms to me that I don't need an upgrade as I already like the feel and shootability of my current bow.

 

[Jethro]

I agree that 278 seems low for a 75/30 set up

 

[Geewhiz]

Well yeah....many guys look at the stats as part of their purchasing process.

Those of us that have been shooting compounds for decades are less impressed with pure stats...and more interested in how the bow shoots and feels.

Real world; A few FPS doesn't matter much.

I understand what you're saying but If a company can't figure out how to actually improve anything on paper then it seams like one heck of a marketing gimmick to just say "don't worry about the pathetic numbers, just worry about how it feels".

Also, I've been shooting compound bows for 20 years and have had more success than most. I'm not saying that to toot my own horn, but just to give myself a bit of credibility when discussing these things.

I agree 100% that a few fps doesn't matter, that's the point I'm making.

 

[Geewhiz]

I agree that 278 seems low for a 75/30 set up

I guess I didn't really expect more just based on comparing the specs. Maybe the chrono was on the fritz. But 75lbs at 30" is a recipe for a quick arrow, hence my rant. haha

 

[sodaksooner]

I think we are kind of at the limit with current technology at this point as far as speed goes. I just picked up a lift x 33 and haven't been able to chronograph it yet, but using calculators, it isn't much faster than my 12 year old Prime Alloy. Actually I picked up a Prime Inline 5 a couple of years ago and it is 10 fps slower than the Alloy at the exact same weight, dl, and arrows, but damn, it is so much more fun to shoot. Much smoother draw, less hand shock and much better balance. Speeds really haven't changed much in the last decade, but they sure are quieter and shoot better.

 

[180ls1]

I understand what you're saying but If a company can't figure out how to actually improve anything on paper then it seams like one heck of a marketing gimmick to just say "don't worry about the pathetic numbers, just worry about how it feels".

Also, I've been shooting compound bows for 20 years and have had more success than most. I'm not saying that to toot my own horn, but just to give myself a bit of credibility when discussing these things.

I agree 100% that a few fps doesn't matter, that's the point I'm making.

It's more likely that you are just not noticing the differences.

What is the reflex of the two bows?

 

[Geewhiz]

It's more likely that you are just not noticing the differences.

What is the reflex of the two bows?

Quite possibly.

I'm not sure what that means.

 

[180ls1]

Quite possibly.

I'm not sure what that means.

It's the amount of torque you can put into the bow if you don't do everything perfect. This is huge for hunting as you rarely do it all right. It also magnifies as distance increases.

I've been in the same boat as you. Unimpressed with every bow I upgrade to. Then after a 6 months or so of shooting I start to really like it.

 

[Skerhunter]

I did not measure the draw weight but I did ask to confirm what the poundage was set at when I picked it up. My buddy who bought a lift x this year is shooting arrows of near identical weight with a 29" draw and 70 lbs and he said his chrono'd at the exact same velocity as mine.

Not surprising - it’s not uncommon for let’s say 60lbs limbs maxed with mods for a max of 28” to be faster than one with 70lbs limbs turned down to 60lbs. Cams/mods/limbs for the same bow are not equal.

Are your mods/limbs maxed out?

IBO is the last thing I look at when trying new bows and yes a lot of the new ones are the same speed as 15-20 year old models.

The focus the last few years has been on improvements in tuning, draw cycle, string angle. I didn’t upgrade bows until the draw cycle was noticeably different than the older bows that started 2-3 years ago.

 

[Turkeygetpwnd38]

I’m guessing you aren’t actually at 75lbs. I chrono’d a 434g yesterday out of my 33. 30.5in draw, 67lbs, 299fps

 

[jmez]

IBO standard is actually 80# +/-2 lbs, 400grain or 5gpp arrow with no specified draw length. Also note the 5gpp does not factor in the +/- on draw weight. Listed IBO speeds by manufactures are likely 82# with a 400gr arrow, and guess the draw length. They are inflated.

 

[Turkeygetpwnd38]

IBO is always exaggerated a bit. It’s shot with nothing on string (peeps/speed nocks/dampeners) and likely a little above weight. I think you’ll like the lift though.
You got me curious though, here’s a 534g arrow at 72lbs, didn’t have time to twist up to 75lbs…





And 434g arrow at same weight