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Gold Tip Online Tool - Build Your Own Arrow

Bolts Arrows Spine FOC Calculator

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#1 rchristoff

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Posted 07 June 2012 - 10:13 PM

Hello Everyone,

The crossbow I'm considering is rated at 385 fps with a 398 grain 20" bolt (200 lb. peak draw weight, 14" power stroke). I called the company and they warrant the xbow for anything 390 gr. and up, so I have been doing a lot of research regarding arrow weight, spine, and foc.

One tool that I found to be really helpful was the "Build your own arrow" online tool by Gold Tip. I have messed around with the different variations and I am stuck between the Laser II Pro and Laser III Pro, as I plan on doing target shooting out to 100 yards; so the shaft weight variation I want to keep to a minimum, but I also want to keep the FOC in the 12-18% range if possible.

I plan on building these myself to make them as consistent as possible and match the spine correctly, however I have a few questions for the experts out here.
  • What is the better spine for the bow that I have described above (Eastman (Carbon Express) Covert CX2) - the Laser II or the Laser III? I really like the math results with the Laser II, but I am afraid the spine may be too weak for this bow.
  • Does anyone shoot a similar setup and what have their experiences been?
For the curious cats out there, I've attached some of the combinations I've found with their online arrow building software. It is really cool to tinker and see the results without buying the arrows.

Lastly, I understand that all of this "theory" cannot match real-life shooting, I'm just trying to avoid re-inventing the wheel if possible...

-Rob

Attached Files


Edited by rchristoff, 07 June 2012 - 10:45 PM.


#2 Cossack

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Posted 08 June 2012 - 08:08 AM

I'm using Lazar II s in my 3 bows and have made arrows - in 22" shafts - with them for brother's fast Barnett, to our mutual satisfaction. BUT, given your purpose, I'd go with Lazar III, last batch of II's I used spine seemed on the light side for my 345 fps Cyclone. Their brass inserts for the Laz III s will ensure high FOC. Using the IIs with 110 gr insert, Blazers or Fusion Vanes and aluminum nocks I get FOC of 18 or 20% depending if 100 or 125 gr tip is used.

Edited by Cossack, 08 June 2012 - 08:23 AM.


#3 beervo2

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Posted 08 June 2012 - 03:34 PM

Out of my SZ380 I found the spine in the Laser III Pro's to be a better option than the Laser II's when shooting a high FPS..
I fletched up some Laser III Pro's with 110 grn inserts & some with Victory's 92 grn inserts, both shoot great, in fact I get the same POI with either one using Blaser vanes..
The Laser III Pro's are very accurate compared to the Laser II's when shooting the SZ380..
Good luck!!

Mike

#4 Guest_vixenmaster_*

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Posted 08 June 2012 - 05:00 PM

X3 on Pro III, the II's are really weak spined fer any crossbow that shoots faster than 345-350 fps

#5 wapster

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Posted 08 June 2012 - 06:41 PM

Well I tried the 3's in the past but they were not the pro's. What did they change to give them the new "pro" name???

#6 beervo2

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Posted 08 June 2012 - 07:08 PM

The Pro series have a straightness tolerance of .001 as opposed to .005, makes a difference as far as I can tell..JMO..

Mike

#7 rchristoff

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Posted 08 June 2012 - 10:11 PM

Great info - thanks everyone! I will definitely go with the III pros, unless UL's new arrows he's been talking about are a better buy :)

#8 445 supermag

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Posted 09 June 2012 - 06:43 AM

I know my next batch of arrows are going to be lazer III pro's.

Brian

#9 wapster

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Posted 11 June 2012 - 06:46 AM

Do the pro's weigh the same as regular III's ????

#10 beervo2

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Posted 11 June 2012 - 11:07 AM

Do the pro's weigh the same as regular III's ????

Yes...

Mike

#11 wapster

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Posted 11 June 2012 - 03:35 PM

thanks Mike........you know....I have lived in Michigan my whole life but I had to look up where Otisville is.....lol now I know though !

#12 beervo2

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Posted 11 June 2012 - 06:32 PM

thanks Mike........you know....I have lived in Michigan my whole life but I had to look up where Otisville is.....lol now I know though !

Yep, it's just a small village about 20 miles north of Flint...

Mike

Edited by beervo2, 11 June 2012 - 06:33 PM.






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