An offer to help

[Todd_ID]

hey todd
125's have helped in tuning. thanks for the idea! if i was to up the poundage on my bow how high would i have to go to get my arrow as close to perfectly spined as possible? the reason i ask is because the broadheads i wanna shoot are very spine sensitive.

thanks!

With your setup you've most likely got 70# limbs turned down to 65#.  I think a Hoyt maxxes out its limbs about 2# over, so that'd be 72#.  And that would make the numbers with the 125 grain heads: 294 fps, 79.9 ft-lbs KE, recommended spine .342, and your's are .337.  That's as close to perfect as you'll find.  Also, maybe the broadheads you want have a 150 grain version?  Increased FOC, closer to your proper spine, don't have to sacrifice turning your bow up to a point where you can't get it pulled back when the blood's pumping and the bull is screaming; win-win-win.

[Button Nubbs]

Thanks again! Is that the archers advantage program?

[Todd_ID]

Thanks again! Is that the archers advantage program?

No problem!  I use OnTarget2 by Pinwheel Software, but Archer's Advantage will get you the same information.

[flinger]

2008 Diamond Black Ice
125 g tips
3 2in blazer vanes
67lbs
29 in. draw
Hope this is enough
 Thanks

[Todd_ID]

Need some more info Flinger: arrow brand, model, spine and length.  If, by chance, you are shooting a 340 Easton Axis cut at 29", then your numbers would be: recommended spine of .364, 270 fps, 440 grain arrow, 71.3 ft-lbs KE, 14.2% FOC, 20-50 drop 32", KE @ 50 is 61 ft-lbs at 249.8 fps.  Nothing at all wrong with any of that, but it was just a guess on the arrows you are shooting.  Post what you are using, and I'll run it again, but they probably won't change too much from these.

[flinger]

gold tip XT Hunter 7595 29.5

[Todd_ID]

No problem.  269 fps, 442 grain arrow, 12.2% FOC, 71 ft-lbs KE, recommended spine .367 (yours are .340), 20-50 drop: 32.6", KE @ 50: 60.3 ft-lbs @ 248 fps.  Nothing out of whack with those numbers.  If it works, stick with it.

[flinger]

how bout my buddys
2010 Z7
70Lbs
30 in draw
30 in ICS Hunter elite 340 3vein 4 in.
100 grn tip
 thanks again todd

[Todd_ID]

how bout my buddys
2010 Z7
70Lbs
30 in draw
30 in ICS Hunter elite 340 3vein 4 in.
100 grn tip
 thanks again todd

Looks like 304 fps, 456 grain arrow, 8.7% FOC, 93.8 ft-lbs KE, 20-50 drop 25.2", KE @ 50: 74 ft-lbs @ 270 fps, recommended spine of .308".

I'd say he needs stiffer arrows if he's going to be shooting broadheads and wants them to fly consistently at all, and the 8% FOC is a bit light for most broadheads.  When he gets new stuff because his isn't flying well, tell him to get the ICS Hunter Elite 300's at 30" with 125 grain broadheads.  Then his numbers would be: 298 fps, 487 grain arrow, 10.8% FOC, 96.1 ft-lbs KE, 20-50 drop of 26.6", KE @ 50: 75.7 ft-lbs@ 265 fps., recommended spine of .298".  All of those are better for hunting, and they should fly like darts.

[bowhunterforever]

What can you tell me about my setup? 2010 matthews Z7, 29inch draw set at 70#,  29 inch Beman 340 ics hunters with 2 inch maxium vanes and 100 grain tips. Thanks

[Todd_ID]

What can you tell me about my setup? 2010 matthews Z7, 29inch draw set at 70#,  29 inch Beman 340 ics hunters with 2 inch maxium vanes and 100 grain tips. Thanks

No problem.  According to the program, you're right at the edge of legal with 6.067 gr/lb.  Shows 300.8 fps, 424 grain arrow, 11.42% FOC, 85.3 ft-lbs KE at launch.  Recommended spine is .314, so your .340's are weak, but may fly ok. 20-50 drop of 24.9", KE @ 50: 72.2 ft-lbs.

If you turn it down to 65# to get spine closer, then you'd get: easier draw with cold muscles, 291 fps, 6.5 gr/lb, 80.2 ft-lbs, recommended spine of .331", 20-50 drop of 26.9", KE @ 50: 68 ft-lbs.

To my way of thinking, there's simply not enough loss in any of the categories to not turn it down, and there are plenty of benefits: the second most important being much easier tuning when you get the proper spine, and the most important is not having to move bow a bit at an odd angle when drawing 10 yards from a monster bull. 

[bowhunterforever]

What arrows should i be shooting beman ics 400?

[Todd_ID]

What arrows should i be shooting beman ics 400?

The 400's would be way too weak.  Think of spine as the amount an arrow bends.  They put the arrow on supports at the ends of the arrow then put a 2# weight in the middle and measure the amount it bends.  One that bends .300" is called a 300 spine; one that bends more, say .400", is weaker and named a 400 spine.  Make sure to ask before you buy, though, because each manufacturer uses different spine-naming conventions.

Lots of IFs in the answer to your question:
IF you want to keep the 70# draw weight
and
IF you are having poor arrow flight
and
IF you need more arrows
and/or
IF you WANT to spend some money on arrows
and
IF you want to stick with the Beman ICS Hunter arrows
then
Look for the ICS Hunter 300's; they'll be a .300" spine vs your .340" spine
also IF you go with the 300's, then you could go to a 125 grain head and be dead center perfect spine with a 29" arrow and get better weight, FOC, and penetration.  Other .300" spine arrows would work fine, too; think Easton Axis or Beman MFX.

Next series:
If you are not stuck on the 70# draw weight
and
If you don't need more arrows
or
If you don't want to spend more money
then
Turn the bow down to 65#.  That solves all your concerns without giving much up.  Look again at the numbers between 65 and 70 pound draw weights above, and you'll find that not much is lost in energy, speed, or trajectory.  Lots, however, is gained by having 5 less pounds to try and draw in the moment of truth.

My strong suggestion is to back both limb bolts out 2 turns and shoot what you have.  You already have more than enough horsepower to blow through a cape buffalo, so dial it down to where it'll just blow through a polar bear.

[boneaddict]

I just bought two dozen arrows, and honestly they were more expensive than my ER visit after I had a heart attack when I paid for them.   WOW, I tie my own flies, load my own bullets, I should be making my own arrows.   

[MIKEXRAY]

Arrows are getting expensive !          I'm shooting my Z7  @ 66# 29 in draw and this program & all the charts say that I am under spined with my Beman ICS 400's  but the Beman chart & the two shops I have talked to say 400 is right in there. On the Beman chart I am a couple of steps away from needing 340's but all the other charts say I am solid 340. My bow shoots sweet but I have been concerned. Definitely mot getting new arrows but just pointing out the differences in charts & opinions. Mike