Bow tuning update

I have been reading and watching some articles about nocking point height, d-loop length, peep height etc, by Alistair Whittingham and John Dudley.

One of the things I suffer from is holding low on the target, and the sight bobbing up and down, which invariable causes me to fight it, and hence introduces tension into the shot. Up until now, I have put this down to me alone. I have even thought it could be a mild form of target panic.

So I read and acted upon a couple of things. First, I am happy that my draw length is OK, so that has remained untouched. But I have played with the peep sight height, nocking point height and d-loop length.

The peep sight height was easy. I moved it down just a mm or so to get a more comfortable view of the scope, especially at the longer distances. In fact all distances feel a little more comfortable.

Next was the d-loop length. This has been shortened by maybe 2 to 3mm. The suggestion was, making the d-loop shorter (if your DL looks OK), would help lock in the drawing arm at anchor. My d-loop was a little long and it caused the arm to floating around a bit, and most likely causing small movements that meant the bow bobbed up and down.

The final and probably most compelling change is the nocking point height, or position, on the string. This is in effect good old fashioned tiller tuning, but instead of leaving an uneven tiller (I shoot a single cam bow, so the tiller is uneven anyway, so in this case, it would mean the limb bolts simply being unwound a different number of turns), the position of the nock point is moved up and down until the aim steadies. As it turns out, my nocking point was about 3mm too high, and after some experimentation, the aim has locked into place. This has also meant the pressure on the bow hand has changed, moving it lower towards the wrist joint, so the pressure of the bow is directly over the bone. Before, it was a little high in the grip. All of these changes together have had a remarkable affect.

For the first time in a long time my aim (when the form is correct) is much steadier, where as before I seemed to always be fighting it. I have only moved things by a couple of mm, but it has been worth the effort.

The video/article in question can be found @ Performance-Archery.tv | Episode 24 | Dot Holding Low and Tiller tuning and holding steady

Monster paper tuning results

Since I got the Monster, I have shot some good scores, nearly all PB's. All of these have been built on really good long distance scores. The shorter distances have been disappointing at times, and its only now I have realised this has been a re-occurring theme.

Sometimes when shooting I catch a glimpse of the arrow and sometimes it kicks out wildly, so I decided to paper tune at 3m (at home, its all I can get), and the results have been consistent.

Each time, after trying different things, I have always ended up with a high-left, 3.5cm to 4cm tear. The high I can explain, but its the left tear. It maybe that I am torquing the bow, even consistently, but I really don't think so, not that badly. Hand placement is always critical in my shot routine, across the pad of the thumb.

I tried the following, with no difference in the results:

• Centre shot 11/16" from the riser, a figure used by many Mathews shooters. The string and arrow is in line with the centre of the grip.
• Shooting @ 59lbs, 56lbs and 52lbs to see if the arrow was too weak (normally shoot @ 59.5lbs).
• Added extra weights on the end of the long rod and side rods to see if this would reduce torque.
• Tried my new Brite Sight rest (arrived today) to see if it would reduce torque.
• Set the nock point from 2mm to 8mm, and upto almost level.
• Shot holding bow deliberately not have ANY string contact with the face.

None of these had any noticeable affect on the tear size.

Now I do need to go out and do a walk back tune, but this has been done in the past and I got the same kick out (although not confirmed with a paper tune).

The next chance I get to shoot in good weather, I am going to perform a walk back test to confirm my centre shot and re-paper tune. Watch this space for the results...

Monster tiller and cam timing sorted

Since I have been shooting the Monster, it has been set with an even tiller but the limb bolts have been wound out a different number of turns to achieve this.

I have since found out that the limb bolts should be wound out the same, even if it means the tiller is not even. In this case, the tiller is about 3 - 4mm difference.

Tonight I changed the set-up to this configuration, and also got the cams back in time (back wall has been a bit spongy but I have been a bit lazy in sorting it out!). I then shot 3 dozen @ 90m and shot a practice PB of 326. The included a couple of sloppy 8's, so it could have been better.

The bow feels really nice now with a solid back wall and the valley doesn't feel so shallow either, so I am able to be at full draw without creeping off the wall.

The moral of the story is, get your bow in tune, its worth the effort!