2 questions on arrows for Pitts. Predator

[Soilarch]

Have a new to me Predator.
63# @28  I think I pull it right around 28".  (Again, I'm not sure because I always just leave my arrow full length.  What I do know is I could take about 1.5" off if I needed to.)

Arrows are Vapor 400s (or 4000s? there .400 spine)
Full length and I've settled on roughly 250gr up front.

Shafts are 8.6gr/inch so about 267gr. Inserts are 14gr. 240-250grs up front and a nock and feathers put me a hair over 8gr/pound.

One...I'm not very good and bareshafting is a booger for me.  225gr consistently but the bareshaft a hair to the left (I'M LEFT HANDED) and 275gr put the bareshaft consistently 2-3 inches right from about 15yards away.

I can't believe I'm not way underspined with a full length .400 and 250gr up front out of a 63# recurve.  Does this sound feasible to anyone?  (Guess I need either encouragement or a "whooaa nelly".)


Second, the thing isn't terribly loud but those same arrows with different points work out to over 13gr/pound for my dad's 45# recurve...now THAT is a quite bow...and I've not even tried to dial it in yet.

Both have wool silencers, my t/d predator also has yarn wrapped 'round the serving that touches the limbs. Dad's is a one piece. Both are shooting 12 strand dacron.

Brace height is around 7.5 on mine, closer to 8.5 on dad's.

Any tips on quieting this thing down or will it be futile when I'm shooting 8gr/pound to get this as quiet as I'd like?

[sbschindler]

first thing I'd do is to use a different arrow tuning method, use OL Adcocks planing method go to this site and you will see.  http://www.bowmaker.net/tuning.htm    
then I'd try and get my arrow weight up to near 10 grains per pound, after that you should be goo dto go. I shoot a predator 60LB at 29 I use a 30 inch Carbon Express heritage 250 and have 280 grains up front for a totla arrow weight of 640 grains  and it shoots pretty quiet and see no ill effects for a flat shooting bow. when the arrow is really tuned to your bow the speed of your arrow is also enhanced. of course this is just from what I see and is my opinion