A Little Confused

[pwiles1968]

I have been gradually increasing the poundage on my bow since I started using it in Feb, I am up to about 56# from the 44# I started at, I am pulling this with ease and have only stopped there because of arrow spine.

Theory says each time I increase the poundage the arrows fly faster and I have a flatter trajectory so I would need to Raise my sight (lower my bow) to hit the same point at the same distance, but after the last few increases in weight I have found I have been actually lowering my sights to hit the same point.

Am I going mad or is there a simple explanation for this.

[Max]

Originally Posted by pwiles1968

I have been gradually increasing the poundage on my bow since I started using it in Feb, I am up to about 56# from the 44# I started at, I am pulling this with ease and have only stopped there because of arrow spine.

Theory says each time I increase the poundage the arrows fly faster and I have a flatter trajectory so I would need to Raise my sight (lower my bow) to hit the same point at the same distance, but after the last few increases in weight I have found I have been actually lowering my sights to hit the same point.

Am I going mad or is there a simple explanation for this.

Could winding in the limbs have altered the knocking point?

[grantwomack]

I'd suggest checking vertical nock travel. Each time you adjust the limbs, you'll need to retune the bow.
The arrows will also come out more whippy as you increase weight. From a compound, arrows flex up/down rather than left/right. They might be flexing too much and pointed down after clearing the bow, much the same as arrows going to the right after increasing the draw weight on a recurve bow (for RH archers).

[geoffretired]

The theory is right so the sight should be going up the scale,away from the arrow rest. It would be worth checking the tiller as it is possible to put more turns on one limb, by accident. I would also check the nocking point position, with a bareshaft check, they can move up the string which has the effect of pushing arrows downhill. The arrow rest may have some part to play in this too. It may be getting pressed down by the more violent arrow launch.

[pwiles1968]

I have been very careful to wind them in the same amount, there is writing on the bolt head and I always make sure it goes round exactly the same amount, the tiller looks ok as far as I can measure, and the bow does not pull up or down on the draw which would indicate one limb being set stiffer than another. My scores have improved (I am still fairly new to this so they should be improving anyway) I am happy with the bow setup for the moment but was just wandering why it should be that the sights have dropped, it may be that I have got to the spine limit on my arrows, they are supposed to be OK to 55#.

I will do some paper tune tests next week to see if the arrow is coming away cleanly, for now I'm not going to play with the bow, I have my first competition on Sunday and don't want to mess up my sights etc, I have some second hand ACC's (3-28 500) coming so will tune the bow for these and see what happens.

[morphymick]

Originally Posted by pwiles1968

Theory says each time I increase the poundage the arrows fly faster and I have a flatter trajectory so I would need to Raise my sight (lower my bow) to hit the same point at the same distance, but after the last few increases in weight I have found I have been actually lowering my sights to hit the same point.

Am I going mad or is there a simple explanation for this.

Only if the arrow has passed the top of its arc. If the arrow is still rising, the sight goes the other way. Field archers know this all too well.

Obvious question is............. at what distance are you shooting?

Mick

[pwiles1968]

Originally Posted by morphymick

Only if the arrow has passed the top of its arc. If the arrow is still rising, the sight goes the other way. Field archers know this all too well.

Obvious question is............. at what distance are you shooting?

Mick

I have been doing 60 and 50 Yds a lot.

[morphymick]

Originally Posted by pwiles1968

I have been doing 60 and 50 Yds a lot.

That's one possibility ruled out then.

Mick

[GeoffT]

Could be that the last changes are making the arrow hit the bow or rest.

[greydog]

It could be, as you mention in one of your posts, that you are at the upper limit of your arrows spine now. As Grant pointed out, compound arrows do flex more up/down......so there is the possability that the extra poundage is causing the arrows to flex more and they are pushing their way through the rest in the middle of the power stroke, and as a result leaving the bow slightly lower than they were at the lower poundage. If the arrow is flexing too much the bare shaft test should show it up as you probably won't be getting fletching contact with the rest