65%

[fletcher]

Looking for some helpful hints (how to) shoot 65% let off bows opposed to shooting say 80%
65% @ 60# = 21# to hold, opposed to 12# @ 80%
I believe nice straight alignment would help the cause and correct draw length
I have heard of some archers pushing hard foward and pulling hard into the back wall to steady themselves.

I am about to move a 65% bow and any amount of info would be appreciated

[Sandy Hancock]

As I'm used to 0% let-off (recurve), I would suggest shooting a lower let-off is a good idea.
Holding more pounds at full draw should improve stability if everything is lined up properly, especially in the wind. I suspect you will also have to use your back more, which should improve your release, even with a mechanical release aid.
Pull strongly into the wall *with your drawing arm trapezius* and wait for the device to go. Should be sweet.

[fletcher]

Thanks for your thoughts Sandy
Does shortening your draw length a little help

[elvanbowman]

Your draw length is your draw length. Have a coach or another member with a draw length jig or arrow check you out at a your proper anchor point at full draw. Once you have that set you can start setting up your bow to suit rather than compensating for a bow that is not set up for you.

I shoot a Mathews:cool: for Fita rounds at 80 percent let off from 60 pounds at 27.5". I have tried it at 27" at same poundage with 65 percent let off( solocams are set up this way as they only have half inch adjust and you are effectively drawing short with less cam rotation hence the lower let off- other set ups such as binary etc would be simmillar in regard to let off vs cam rotation as the cams set ups run off the same principle as a block and tackle but with fixed axles hence the cam profile effects the mechanical advantage in this case hold weight generated and the amount of rotation will effect the profile thus the eventual hold weight) and I found that I shoot far more consistant groupings at lower holdweight that suited my drawlength more appropriately.

Spose I have gone on a bit, but hope this helps:smile:

[fletcher]

Hell year bowman that was a mouthfull,I appreciate your input
From what I have heard some archers have been shortening their draw lengths a little to shoot lesser let off bows and holding steadier.
They feel they are taking more of the weight in their back ..?

[elvanbowman]

Thanks for the positive feedback, hope the info was some help:smile:

[Progen]

Not to jump on you, elvanbowman, plus I'm a 'fulltime' recurver but I've read from quite a few sites that lower letoff which equals to more holding weight helps maintain better form which tend results in better groups.

[slick]

Irrespective of what you

[REIDY]

I think that you also need to consider the fitness aspect when changing from 80% letoff to 65%.

65% should be stronger in the wind and I believe will give you slightly higher arrow speed because of the higher beginning point. However, it is no use shooting a few points higher at 90m if you can't draw the bow by the time you get to 30m.

That 9lb difference will make a difference over a full FITA.

Pete

[fletcher]

I would be keen to get the thoughts and how to's of more compounders as well

[Progen]

I would be keen to get the thoughts and how to's of more compounders as well

I think that doesn't include us, slick. :mad:

:p Ok, found something interesting for you, fletcher. And I didn't think this up during the lunchtime siesta. :rolleyes:

If you've ever shot a heavy Recurve or Longbow, you've certainly noticed that it takes a lot of strength and skill. A traditional bow has the most draw weight when the bow is at full draw, so you must aim and release the arrow quickly before you run out of steam or begin to shake. Compound bows are designed to eliminate this problem, offering the shooter more time to aim and release the arrow. In contrast with the traditional bow, the draw weight of the compound bow decreases (sometimes dramatically) at the end of the drawstroke. This is known as Let-Off. Early compound bows featured a 35-50% let-off, a welcome relief. But today it is common for bows to have let-off in excess of 75%. A bow with a 70# draw weight and 80% let-off will require the shooter to hold back only 14 lbs. once the bow reaches full draw. Holding back such a small amount of weight, the shooter has the luxury to take more time aiming and releasing the arrow. Of course, you can have too much of a good thing. There is some concern that a bow can have too much let-off, making the bow feel "sloppy" at full draw. Maintaining some level of resistance at full draw is necessary to keep things in good natural alignment. However, the average archer will find the mid to high let-off bow to be more comfortable to shoot. Advanced archers and back-tension shooters often prefer a little less let-off. The only other disadvantage to a high (over 75%) let-off cam is a small reduction in arrow velocity vs. a lower let-off cam system. All other things being equal, a bow with 65% let-off will shoot faster than a bow with 80% let-off. However, the difference in speed is usually only a few fps. Fortunately, many cams use interchangeable modules which give you the option to easily switch between different available let-offs. Some cam systems, such as the High Country XD Cam, the Bowtech Infinity Cam, the Browning Cyber-Cam, and several others, offer adjustable let-off right on the cam without the need for additional modules.

However, there's a bit of a technical snafu here too. Bear with us, this takes a little time to explain. Depending upon how you compute the let-off percentage, you can get two clearly different let-offs for the same bow, the "Effective" and "Actual" let-off. While you're drawing the bow back, friction in the bow's cables, cam bushings, cable slide, etc. adds a little draw weight to the cycle. Unfortunately, the extra energy you used to overcome that friction gets lost when you let the bow back down (or fire the bow). So basically, the bow doesn't put-out as much energy as you put-in. Some of the energy is stolen by friction (hysterisis). Bummer!

So it would take more energy to draw the bow all the way back, than it would to hold it while slowly letting it back down from full draw. It's kind of an abstract concept, so imagine if we put a bow in a vice and then drew it back using a rope and winch. Now imagine we also had a spring scale hooked to our winch, so we would know exactly how much pressure was on the rope at all times. If we started drawing back the bow by cranking the winch, and watched the reading on the scale the whole time, the weight would go up and up until the bow reached it's peak weight (about 2/3 of the way back). As we keep cranking on back to full draw, the weight would drop-off as we arrived at the draw cycle's point of let-off (full draw). NOW! If we reverse our winch and slowly let the bow back down, we should expect the scale to read the same, just with the cycle in reverse, right? Nope! As soon as we begin letting the bow back down, all the readings will be slightly less than they were when we drew the bow back. This degradation or loss of effective draw weight due to friction forces is called hysterisis.

SO......To compute our percent let-off, all we need to know is the bow's peak weight and it's minimum weight (at full let-off). But when you measure the peak and minimum weight, you'll get slightly different numbers depending on if you're in the process of drawing the bow back or letting down. Here's an example. Let's say you draw the bow back and the peak weight is 60# and the minimum weight at full let-off is 15#. But when you measure while letting the bow down, the peak is only 52# and the minimum at let-off is 13#. If you compute the let-off using either set of figures (15/60 or 13/52) it's easy to compute that at full let-off you're holding back 25% of the peak weight. So this bow must be a 75% let-off bow, right? AH-HA!!!!! Finally!!! Here's where the technical snafu comes in.

Some manufacturers play a little trick when computing their let-off percentage. Instead of using the matching set of numbers, they choose the high figure from one test (drawing back) and the low figure from the other test (letting down). And if they use the 60 from one test compared to 13 from the other, the math comes out a little different. If we compute the let-off with 60 vs. 13, we get just over 78% let-off. And since let-off is usually listed in 5% increments, round-up and viola! 80% let-off! So in our example, the bow would have an advertised or "Effective" let-off of 80%, but it's "Actual" let-off would only be 75%. Tricky, eh? And of course, one could argue that the extra 5% really doesn't matter. But if that's the case, why fib about it in the first place?

So be aware. You may not be ACTUALLY getting as much let-off as you think.

ps. Give me some time to find those articles about letoff affecting form. Can't remember where I read them from.

[fletcher]

If I have understood correctly Bernie Pellerite's shoulder allignment is quite different to James Parks. What is everyone using?

[Progen]

Ok, more information but still can't find the one about letoff influencing form. :mad:


[QUOTE=www.skookumarchers.com]The decision to shoot an 80% letoff versus a 65% letoff bow is one that needs to be looked at carefully before a choice is made. With the amazing number of excellent bows on the market today, one should consider several factors before making a final choice. The first question to ask yourself is,

[fletcher]

Hmm interesting reading Progen I would like to get a look at the affect on form v let off
Thanks for your efforts

[elvanbowman]

Good info well found progen!:smile:

[Progen]

Hmm interesting reading Progen I would like to get a look at the affect on form v let off
Thanks for your efforts

That's the one that's ruining my hour now. Can't seem to recall where I'd read those from. Didn't save them because they're not relevant to recurve archery but I was dead sure that it mentioned something about being better for target compounders to go for lower letoff as the higher holding weight helped to stabilize form. Better not quote too much just in case I read or remembered wrongly. :mad:

Anyway, for what it's worth, all the local compounders go for lower letoffs (IF their bows came with that option) although most of them were just following the pro shop guy blindly.

[fletcher]

The amount of quality information out there is amazing, putting all into play can sometimes be some what more difficuilt.
Thanks for your efforts Progen.