I just got a new string and am ready to set up my bow.  This is the second string I have had for the bow and have a few questions.  I measured my brace and nock point of the old string and set the new string up to the same measurements but when I shot a bare shaft, it shows that I am too stiff.  What do I have to do to get it shooting straight again?  I added some twists to the new string to get the brace measurement the same as the old string.  

Thanks

Is your new string the same material and number of strands as your old string?  Does your old string have silencers on it?  Both will effect arrow tune.

The old string was Dacron and the new string is B55.

How is your nock fit,I know the B55 is a larger diameter per strand.Are both strand counts the same?Maybe shoot the new string a bit until it settles in and then check your bare shaft.

The old one was a 16 strand and the new one is 14.  I will shoot it for a week before I go crazy.  I added string silencers and that helped a lot.

After a few hundred shots, if the shaft still shows stiff, raise the brace height 1/8" at a time until the shaft flies a little weak. When the shafts are fletched they should shoot good groups.

Regards,
Grouse

Typically set a new string such as B50 approximately a 1/2" high and shoot her at least 100 times before attempting to tune a shaft.
Would have silencers installed for at least the last 25 shots.

Key for me is know when the shaft starts to show weak.

Thanks for the advice.  I will put some shots on it over the next few days in the basement.  After that, I will play with brace height.  I will watch my brace height to see if it is stretching at all.

I have taken 40 shots so far and lost 5/16" of brace so far.  I will give it another 60 to break in and then measure again.

QuoteOriginally posted by wisconsinteacher:
The old one was a 16 strand and the new one is 14.  I will shoot it for a week before I go crazy.  I added string silencers and that helped a lot.

You added silencers and that helped? Should have made bare shaft act stiffer. Right or left Hand shooter? which way was bare shaft planing?
Try less point weight to see if your actually weak and getting a false stiff reading with bare shaft.

Well I shot over 100 shots on the string and it did not move the last 25 shots.  From there I was still showing I was over spined.  I put the old string on and you guessed it, over spined.  I guess I did not have my arrows set up correctly in the first place.  I am shooting GT 3555 full length with 100 grain inserts and 100 grain points.  It shoots broadheads well.  I guess now I need to look at some new arrows so I can do this right.

I am shooting a 45# Bear Grizzly.

Yep, either weaker spine arrows or keep upping point weight until she tunes but that may make the arrow to heavy for you.

You can also either reduce the size/weight of the silencers or move them towards the tips a little to soften dynamic spine.

If your strike plate is thick you can replace it with a thinner one and that will soften dynamic spine.