Arrows/Bolts....HELP

[Dryridge]

While I was considered a local Bow Guru....I am completely lost now that I have been forced to horizontal archery.

That said, I have a 200# Horton Hunter from Cabelas. It shoots what I would call decent. The thumbhole needs augered out some to fit my big paw. I am shooting 3" to 8" groups up to 50yds. Not great I know. I could make arrows rattle at those distances with my Hoyts.

My question is this...I currently am using 22" Carbons w/100gr heads and a local shop told me to go with 20" and a 125gr head. Now when I try to apply vertical archery theories to horizontal archery arrow selection it simply doesn't fit. Grs/lb is out the window. Is it all just pure spine? If so the 20" version would be stiffer I assume.

Any help with arrow/bolt selection theories and ANY tip on tuning and shooting more accurately would be helpful. Remember I am a former prostaff shooter and full fledged, card carrying member ofarchery tinkerers annonymous so I need some help getting started tweaking on this thing.

Thanks in Advance for your help

Dave

[Stan00]

http://www.archerytalk.com/vb/showthread.php?t=747024&highlight=arrow+tuning

This worked for me.

[smokepolehall]

3" to 8" groups out to 50 yds. offhand or rest ? if by rest then ck cam timing as string stretches. i prefer the longer arrows with big FOC and weight up front. unlike vertical Bows that have 26" up to 33" to stabilize. our CB's use rather short arrows so the nose leads and the butt follows!

[Dnk]

Too bad you were forced into this, there is no shame is using these hunting tools. I still shoot an UltraTech and a Vulcan and a few traditional bows. I certainly am not ashamed of anything.
There is very little tuning to do here. You have to think in terms of Traditional bows. Because the shaft length and the ride against the rail Archer's Paradox has less influence in the crossbow compared to it's vert brother. You can change things like shaft weight, arrow weight, broadhead selection (weight or length), brace height, FOC and string material.
One thing you may have to contend with is the garbage you may or may not have been fed. Crossbows are hardly as accurate or easily accurate as a compound.
As crossbow shooters we do not have libraries of information short cuts to accuracy and fine tune our equipment. Basically you have to fart around and experiment.
I would suggest that you're problem is not spine as it sounds like you have a consistent problem. A shaft that is consistency too stiff should not be inconsistent. If that is your group size from a rest then you might want to start with the basics like a nut and bolt check, arrow/fletching clearance and scrutinizing the scope/mount set up.
Good luck and you're questions will be welcomed.

[Cossack]

Crossbows are a whole different breed. My arrows fly best when endowed with high FOC, much higher than for a vert. The length of the arrow should not matter that much given the speed of your bow but get the weight forward.
In my 355 fps bow, I'm using 20'' Gold Tip Lazer II's, with 110 gr brass inserts and 2" Blazer vanes, plus 125 gr heads, for an overall weight of 425 and an FOC over 20%. For serious work I use 125 Slick Trick Mags.