View Full Version : OT2 program

12-11-2011, 03:45 PM
Any of you guys have this program and would be willing to run my numbers thru it? Thanks.

Hutch~n~Son Archery
12-11-2011, 04:11 PM
Here is a trial version you might be able to download a run you numbers.


12-11-2011, 04:42 PM
Tried that Hutch and it won't work. Someone running it for me on AT.

Hutch~n~Son Archery
12-11-2011, 04:43 PM
Sounds good at least you will get what you need.


12-11-2011, 05:03 PM
I hope. Jerry at Southshore archery thinks I am spine weak with the 5575s possiblt since I can't seem to get the kick out. May need to try a bit of a stiffer spine and thinking 7595s.

12-12-2011, 05:12 AM
Just ran the numbers from the specs in your sig line, OT2 shows that as near perfect, just a little on the stiff side but well into the green. Those should tune without any problems. A 7595 will be way too stiff. You may want to check for fletching contact and/or maybe try adjusting the idler lean a little or centershot.

12-12-2011, 07:43 AM
Again, there is any easy way to see if they are the right spine and not too weak. Drop the bow weight to 60# and try tuning from there. It's cheaper than new arrows at this point. Don't forget, computer programs can't take into account any human induced torque to the bow so although useful are not absolute.

12-12-2011, 11:10 AM
You may want to try different weight field points.A heavier point makes the arrow react as a softer spine and lighter as a stiffer spine.I'd try some 125 gr and 75 gr points and see what you get.Again it's cheaper than new arrows.Wish you luck.

12-12-2011, 02:07 PM
Thanks for all the input guys. Still looking into other possibilities. By adding the weights according to programs even OT2 says I am borderline weak. I did have the left kick even without them in with the 100gr tips & bhs. Only reason I was looking at the stiffer spine is when I took a couple old xx75's at the same length and tips minus the weights they shot perfectly straight out to 50yds with blazers and zero kick. Oh well it's a long winter up here to work it out.

@ bfisher I dropped the weight after installing the new strings and same outcome. Only thing that flew straight and true was the old xx75 2315s cut to 27 1/2 with those blazers

12-13-2011, 04:49 AM
When I run my numbers thru OT2, I always use the "Hunting" filter in Spine Match.

Running your set-up the same way, w/27.5" GT (assumed XT Hunter) 55/75 shaft, GT nock, Blazers, 100gr pt, it did show spine just slightly weak of dead center in the green "good" range. (theoretical optimal spine being .3977)
The XX75 2315 was much stiffer. For comparison, the GT 55/75 calc'd .400 spine and the XX75 2315 at .342......the GT 75/95 is a .340 spine

As bfisher says, dropping draw weight should have shown spine related problem, but I'm guessing in this case, it may haven taken a drop all the way down to 57-58lb area to equal what the 2315 did, or what I assume a GT 75/95 would do. (FYI: looks like a 75/95 calc's 266fps.....which IMO isn't bad)

I've tried a couple .400 arrows out of my Bengal (spec in sig) and got them to shoot ok w/fld points, but found it shoots really well, broadhead AND fld points, with the stiffer .340 spine arrow.

12-13-2011, 10:31 AM
Mac user - can't run OT2 =(

Curious about checking what this might say about my current set up. I think someone ran numbers for me once before and I was a toward the weak end with what I gave him to plug in. Thinking about getting some new arrows at the end of the season, my GT Velocity are running low - been looking into HT2 in their 350 to give me a touch more spine without having to jump to the 300 and be way over.

12-13-2011, 02:13 PM
@ RLW thanks for all that great info. I dropped my weight all the way to 53# without knowing it until I took it in to be reset to 65# after installing the new strings. It had had a slight left kick since I started shooting it last January. I have turned the nocks with the cock vane out now and am going to check fletch clearance again. According to QAD if the rest is timed right even though they recommend up as it has been it should shoot no matter which way the vanes are. Not a speed freak since my hunting shots are no further than 30 yds and normally under 20. Anyway am going to try the 340 spine and see what happens at 29" per GT should be right on as well. Going to go back to square one on tuning and see how it all works out. Winter is long up here, lol.

12-14-2011, 03:29 AM
[QUOTE=parttimr;78348................going to try the 340 spine and see what happens at 29" per GT should be right on as well...........[/QUOTE]

Be careful, going to a longer shaft effectively weakens arrow too.......and you'll lose about 3-4fps vs the 27.5".
It will be stiffer than the 55/75 and should still be fine, but just wanted to make note of it.

12-14-2011, 03:09 PM
@ RLW only reason I was looking at the 29" was it corresponds with GT chart for my set up. Still gotta see. If I can get the 55/75 to tune will stay with them and with the 75/95 at that length could be easier to give a deal to someone when they have room to shorten them.