A string nock problem?????

[monterey]

I have a bow that came to me via the TG  trade a few years ago.  It's a KennyM r/D design.


I gave the bow to my grandson a couple years ago and he has shot it quite a bit.  Yesterday he said that the string is jumping out of the string nocks after the arrow leaves the bow.  It unstrings itself.

I've not had a chance to look at it yet but it always seemed to have shallow grooves in the string nocks.  

Any other thoughts on what is going on?

The only thing changed with his shooting is a new set of arrows that are about 50 gr lighter than the old ones.

[kennym]

More shock to bow with light arrows, deepen the nocks a bit.

Check for limb twist, highly improbable an a longbow.

Check for nocks to be even across limb.

I don't think I built it, but if I did, send it to me and I will fix it!

[monterey]

No, you didn't build it but was built off your blueprint.

Thanks for those suggestions.  I'm going to adjust the nocks they look shallow.  The new arrows are a bit over 10 GPP but maybe the slightly less weight is the proverbial straw.

[Roy from Pa]

Did the string unravel and lower the brace height?

[kennym]

Or loops too big?

[monterey]

Loop's seem OK.  No unravel.  Once I get my hands on the bow I'll post some pics.

[Robertfishes]

I was working on a KennyM design longbow 2 weeks ago when a friend texted me and asked what I was doing.. I was working on his bow so I took this picture and sent it to him..its ugly since I'm still shaping it..  but you can see I leave some "shoulders" on the string grooves, I assume this would help keep the string on any bow?  

[Robertfishes]

recurve tips but show the shoulders of the string grooves. Like Kenny said maybe the loops are a little too big? But it sounds like everything was good before the new arrows..

[kennym]

Nicely done Robert!  

[monterey]

Those are good looking nocks.  I tend to make them along those lines also.  Not sure when I can get him over here for the fix, he's helping his dad in the business.

[monterey]

Ok, he brought the bow by today and it seemed that the nocks were too shallow all around.  After taking them down and raising the brace height a bit the problem is eliminated.

I forgot to take pictures      

I set brace height at 7 1/4".  What do you KennyM shooters set up at?

[kennym]

Mine usually end up at 7ish.

No pics? Roy will say it never happened!  

[monterey]

Roy is a little quiet lately.  Musta been his thumping arm that he had surgery on  

[Roy from Pa]

Yes it wuz..  

Glad ya got it fuggered out ole boy...

[Robertfishes]

Roy, I sure hope you can bait a hook..its fishing season for all those tastey fish in your pond..I need to get out and catch some bream and shellcrackers myself..