Over Spine Arrows?

[bolo7735]

I'm shooting a 55lb @ 28" Centaur. My draw length is around 29". Arrow length is 31". I am using Easton FMJ 400 spine w/ 75gr insert and 220gr Muzzy. The arrow shoots fine but wonder should I have use a 500 spine instead. Grouping at 12-15 yards have been fair. Groups are 3"-4" and no porpoising. Will going 500 spine will give me better groupings?

[rraming]

lighter arrow with less tip weight, I use 400 spine with 225 up front on 54 lb recurve and it works well, I don't want any less weight than that, they come out around 525 grains. Bareshaft one and find out, I never go by where they hit and grouping, that could be you. You could paper tune as well

[Friend]

If the arrows is properly tuned, then I would expect you groups sizes to remain unchanged.

You set-up however already appears too far underspined and mimmic an upper range EFOC to Ultra-EFOC set-up spine requirements which this one is clearly not. Bareshafting is one viable method to reveal tuning issues.

[Shawn Leonard]

Spine would seem about perfect to me as you have it. If you went to .500 spine you would need to go to a 30" shaft and quite a bit less weight up front, down near 160-175 grains of point weight. I think you are pretty close now! Shawn

[Shawn Leonard]

I will also say that just because you are grouping that does not mean your spine is correct. Your hair covered computer adjust pretty quick and even arrows that are way out of spine will start to group after several shots as your brain takes over for ya. That said I think you are darn close on spine the way you are set up. Take a piece of newspaper stretch it over some old lawn chair or build a little stick frame and get the newspaper nice and taunt. Now go back 12-15 ft. and shoot an arrow thru the paper with proper backstop of course, make the best release you can with out dropping your bow arm. If you get a center hole and 3 perfect tears from the feathers you are good to go. That way you do not have to bareshaftof anything. Go on line and do a search for paper tuning and it will tell you how to read the tears and what to do to correct them. Shawn

[bolo7735]

Thank you everyone for your help.

[drewsbow]

I'm with Shawn on this one , sounds like you should be right close . Drew