Stu's calulator

olddogrib · August 09, 2014, 01:53:00 PM

I was playing around on Stu's calcualtor to see what it would tell me I would need regarding additional length & point weight if I wanted to go from a .500 spine to a .400, just to get a heavier hunting shaft and have them spine the same (all else being equal). It looks like I'd need approx. one inch more length and 50 gr. more point weight. Am I "dumming" something up(always a possibility)....I thought it'd take more than that on both counts.

Cavscout9753 · August 09, 2014, 08:30:00 PM

The one lesson I walked away with from carbon tuning, and I have no doubt you already know, is that 1" of carbon accounts for serious changes in spine. Carbons for me seemed to be able to handle a wide variety of point weight changes (anywhere from 25-75 grains in some cases), but just a 1/4" in cut or length was a huge effect. An 1" of difference in length is a drastic effect on spine for carbons. Just my experiences though.

olddogrib · August 10, 2014, 07:15:00 AM

Lucas,
Thanks for your feedback and more importantly your service to our country. My son is career and was a cav scout. Forgot the designation for that one, but before that I think he was a 13 Papa, MLRS fire direction specialist. He's done 3 year-plus tours in sunny Iraq in the last 10, but thankfully he's stateside now and doing a 2 year stint at Benning as a drill Sgt. He already has his next assignment....Hawaii!!, so things are starting to ease up a bit for him. The average civilian has no clue to the sacrifices you guys make. Thanks again!

Cavscout9753 · August 10, 2014, 10:51:00 AM

Thanks! Ironic as I am also at Benning but with no such hopes as going to hawaii afterwards, haha. Yes, after 4 tours to Iraq I'm enjoying a little TRADOC time as well - I teach Armor Lieutenants at ABOLC. Happy shooting!

August 10, 2014, 04:48:00 PM

I shoot Gold Tip XT Hunter black shafts, and for me to go from .400's to .500's, I have to cut off 2" in length using the same 100gr brass inserts. Seems within reason to me that 1" of length and 50gr of weight change would do about the same thing.

Bisch

Wheels2 · August 10, 2014, 05:03:00 PM

I can shoot a Goldyip Kinetic in .500 or a Easton AftErmath in .400. Both full length with 125 tip. The difference is that the Aftermath are larger in diameter so the arrow sits more left of centershot. The Aftermaths also hit a bit higher even though heavier. Again likely due to diameter.

olddogrib · August 10, 2014, 07:19:00 PM

Wheels,
You sure you don't have that backwards? I would think the Easton would have to be the smaller diameter. Then it would stand to reason their centerline would be closer to the riser centershot and could require less bending going through paradox. The .500's are weaker and flex more, as would be required if they were sitting "more left of centershot" due to a larger diameter. (assuming a RH shooter, but a for a leftie they would still sit further right)

Stu's calulator

olddogrib

Cavscout9753

olddogrib

Cavscout9753

Wheels2

olddogrib