short draw and limb length?

ozy clint · November 13, 2011, 04:13:00 AM

a mate of mine has a short draw of about 26" to the grip. he shoots a 62" take down recurve. is a short draw more efficient with longer limbs or with shorter limbs?
my bow is a 58" take down recurve and i draw about 27" to the grip. just wondering if short draws are better with short bows and vice versa?

John Havard · November 13, 2011, 10:03:00 AM

Clint,

Every bow I have ever tested proves that (all else being equal) longer limbs store more energy than shorter limbs. If you have the same exact bow design, only one with longer limbs and the other with shorter limbs, the longer limbs will out-perform the shorter ones. That is true at 24" of draw, at 26" of draw, at 28" of draw, and at 30" of draw.

The difference in performance is not huge, so the difference between choosing a 62" bow and a 60" bow is minimal. However, at shorter draw lengths an archer needs all of the performance he/she can get. Longer bows will provide more performance than shorter ones. So short draws (and long draws for that matter) will get better performance from longer bows rather than shorter bows.

Night Wing · November 13, 2011, 10:10:00 AM

In my opinion, the longer bows are better no matter the draw length.

November 13, 2011, 01:01:00 PM

We had the chance to test this with our Bear takedowns when the chronos came available. The shorter limbs won for speed. If you take the longer riser and the shorter limb and compare it to the shorter riser with the longer limbs, the bow with the shorter limbs wins. It is all about how any individual bow loads up its energy, I cannot see how making a generalized proclamation will hold up for all bows. There are some bows that are very short that are very slow, it is not due to their length, it is because of the floppy limb design so they don't blow up at a longer draw. A short bow designed to be drawn short will out shoot its big brother that is designed to have a longer draw when both are drawn shorter draw lengths. My wife's Lost Creek NAT is an example of this. At just over 26" draw it shoots an extremely fast arrow for it poundage. Longer similar Lost Creeks do not perform at that short draw as good as her bow by a noticeable margin. It is possible to get a longer bow to shoot faster by having less of the limb working, as in the case of the Jack Howard Gamemasters. With Hill style bows it is possible to get more performance out of the longer lengths by whip ending the tiller, but if the same was done to the shorter Hill style bow, the shorter one attains the same speed with a less of an exaggerated whip end tillering. Considering all things, if all things were close to equal, I prefer the longer length for shooting qualities and the shorter length for handling. Byron Ferguson suggests using a two inch shorter bow for hunting than for target work as a short draw insurance policy, to maintain expected performance,as people tend to draw a bit shorter at game quite often.

Bjorn · November 13, 2011, 02:15:00 PM

If the design stays the same the longer bow will outperform the shorter one at any draw is what I have experienced.

John Havard · November 13, 2011, 03:08:00 PM

I have tested literally hundreds of bows and bow limbs and can say that in similar designs longer limbs have always had more SE/PDF and therefore out-perform shorter limbs. Out of hundreds of tests I can say with perfect confidence that I have never found an instance where a short limb of the same design outperforms a longer limb of the same design. I design bows for a living now (my engineer nerd side) and am quite interested in what makes bows tick and perform.

Precise energy storage measurements are required to observe this, and the difference in speed must be measured with a shooting machine. Usually the difference in say a 60" and a 62" set of limbs (same design, same manufacturer, same brace height, same string weight, same EVERYTHING except length) will be one foot per second or so. Unless the archer is a shooting machine like Rod Jenkins, shooting a bow by hand renders data that is too imprecise to measure the kind of differences that are observed.

cacciatore · November 13, 2011, 04:36:00 PM

Is it true for both recurve and longbow?

Javi · November 13, 2011, 05:00:00 PM

Shorter limbs can be faster than longer limbs on the same riser.. it all depends on how the limb loads.. afterall a bow is nothing more than a spring..

wingnut · November 14, 2011, 09:04:00 AM

"short draw of about 26" to the grip" and "i draw about 27" to the grip"

Heck AMO draw would be 27 3/4 and 28 3/4. Not really short draws at all.

With the same bow and the same weight at your drawlengths, you will be 4-5 fps faster.

You can make up the difference with a high end designed limb. But if you shoot the same setups you can't make up for extra draw.

Longer limbs will shoot faster then shorter limbs of the same design every time. Believe me John does all of our testing and we have reames of results to support it.

Also last year Blacky tested four identical BW curves. The only difference was limb length and the longest bow was the fastest.

Mike

KentuckyTJ · November 14, 2011, 09:11:00 AM

QuoteOriginally posted by John Havard:
Clint,

Every bow I have ever tested proves that (all else being equal) longer limbs store more energy than shorter limbs. If you have the same exact bow design, only one with longer limbs and the other with shorter limbs, the longer limbs will out-perform the shorter ones. That is true at 24" of draw, at 26" of draw, at 28" of draw, and at 30" of draw.

The difference in performance is not huge, so the difference between choosing a 62" bow and a 60" bow is minimal. However, at shorter draw lengths an archer needs all of the performance he/she can get. Longer bows will provide more performance than shorter ones. So short draws (and long draws for that matter) will get better performance from longer bows rather than shorter bows.

I would take this response to the bank.

bswear · November 22, 2011, 10:47:00 PM

Ok, but what if you have the same limbs and two different riser lengths? Will the #3 limb for example perform better on a B riser vs the shorter A riser? By perform I mean speed, energy, etc not how forgiving(whatever that means).

bswear · November 22, 2011, 10:57:00 PM

Quote:
"Byron Ferguson suggests using a two inch shorter bow for hunting than for target work as a short draw insurance policy, to maintain expected performance,as people tend to draw a bit shorter at game quite often."

Anyone pondering the above quote besides me? I think it may make sense to hunt with a shorter bow but I don't think it's gonna save you if the "fever" causes your form to vaporize.

Ground Hunter · November 22, 2011, 11:00:00 PM

I've learned not to argue with physics or gravity.

Joe Subler · November 23, 2011, 08:44:00 AM

I'm a bit confused (which doesn't take much at my age!!). If I have a takedown recurve with 2 sets of limbs that make a 58" bow and a 62" bow and a true 25" draw length and brace of 6 - 7 inches wouldn't the 58 " limbs be working more and thus more efficient? Also, if longer limbs are better why do most bowyer websites (that have draw length tables listed) usually recommend shorter bows for shorter draw lengths?

Thanks,
Joe

RonD · November 23, 2011, 08:51:00 AM

I draw 25" on a recurve and a little over 24" on a longbow. I shoot a 60" Marriah Thermal recurve that has a design more along the lines of a static recurve and get excellent performance with the longer limbs rather than the shorter and can shoot heavier broadheads. With the longbow I shoot a Sentman 64" bow with a slight r/d to the limbs and it performs better than the 56" hybrid longbow I own. Both longbows are cut to center so that I can shoot a wider range of spines. I also, because of my short draw length, like to shoot a low a brace height as possible to increase the power stroke. I don't concern myself with speed since I like to shoot at game at 15 yards or less. Preferable less. This is just my slant on things as a short draw length and low draw weight shooter. My primary go to recurve is shot at 25" at 43# and my second recurve is shot at 25" at 48#. My longbow is shot at 24 1/2" at around 43# to 44#.

JamesKerr · November 23, 2011, 08:52:00 AM

I would think the shorter limbs would work better at that draw because you are getting more of the limb to bend thus creating a longer power stroke.