DR ASHBY ON LOW POUNDAGE BOWS ?

[EIGHTWGT]

I saw a couple of posts where people had mentioned Dr Ashby was/ had done a report yet to be posted on low poundage bows.
Can anyone elaborate on this fact ?  Shooting a 43# hybrid of my own making and really liking the low draw weight I am very interested in this report. I have after reading the 'Ashby Reports' switched to grizzly broadheads, and higher weight arrows (12gpi) with EFOC... Id like to read more...

Thanks guys

Tom

[Shifting Shadow]

I, also, am interested.

[Night Wing]

I have two bows, 42# & 41#. My total arrow weight is 550 grains, with a 150 grain Wensel Woodsman broadhead on the business end, so I'm shooting a little over 13 grains per pound. These arrows work very well for me on deer and small 200 pound and under hogs. Don't know how they would work on a 250 pound or more hog since I've never encountered one while bowhunting.

[michaelschwister]

Don't have any insight into Dr Ashby's research, but a buddy of mine has recently gone from high poundage bows to short recurves in the mid 40# range. He downsized due to damage from the rigors of an adventurous life. The good news is his shooting has been unbelieveable, much better than I have ever seen him, he is killing deer better than ever, and he has been bowhunting 40 some years. If a deer walks by within 30 yards it is good as dead, and he is getting pass throughs with the same arrows he shot out of his 60+ pound bows. I have been a fan of 70# plus bows for years, but after seeing him I plan to move below 60# with my next bow. As someone once said a 40# bow with a 400 grain arrow can kill a moose. I know my buddies 40# bows and 500 grain arrows are more than up to moose, bear, and elk.

[sgrogg]

Tom,

I went down in draw weight to a 45 pound Martin Hunter this year.  Shooting CE Heritage 150's, 160g STOS with a 40 g adaptor, for a total arrow weight of 550 g.  My EFOC is 19% which, according to Dr. Ashby, is on the low end of EFOC.  I've found that I'm shooting much better also with the lower weight.

Shot three deer so far this season.  Two bucks both field dressed 180# and a doe that I'll probably get 2 or 3 sammiches out of.

One, 12 yards, broadside through the heart, complete pass-thru.  Second buck, 20 yards, hard quartering away shot in the ham/femoral, did not pass thru.  And lastly the "2 sammich doe", 20 yards, quartering away, entered between the 3rd and 4th rib from the back, exited out the opposite leg and broke it.

So, 45 pounds is plenty for deer as far as I'm concerned.  Plus I can practice more shooting the lower weights, which is a good thing.  I also like a heavy 12 gpi arrow and the relatively high FOC.  YMMV.

[O.L. Adcock]

The good Doc is collecting more data and will tie that in with UHFOC's. Just looking at his existing data he gave minimum speeds for an 840 grain arrow (I think it was) to consistantly reach the off side ribs of a buff...I can exceed his numbers with a 47# bow drawn to 30". It's not the horsepower, it's how fast you use the horsepower you have....O.L.

[RonD]

O.L., what about a shooter whose draw weight is 41-42# with a 25" draw length? Would draw length be an important variable in this equation? Not trying to be argumentative, just interested in this aspect of archery and bowhunting.

[blueline]

Eightwgt + FL Does that = bonefish??????

OK to the ???at hand.  I still beleave in the maximum efficienticy(sp) of a bow. That is the most energy into the arrow that will fly the straightest. I see folk quite often that shoot 6" to 7" groups that with a well tuned arrow will cut that in half, sometimes it is us , but I want the best tuned equipment I can get. That hopefully will gain in shorter recovery(dead quicker)...

P.S. I no longer own my Blackswan 85#er

[Sharpster]

On the wheelie bow sites I have read many threads where the guys are constantly trying to attain "More speed and K.E.! More speed and K.E."!   :rolleyes:  

That's fine but, without also adding MASS, adding speed does very little to improve K.E.

I would like to see a penetration test between a 300 gr arrow shot from a 60 lb. wheel bow at 280 fps and a 600 grain arrow shot from a 45 lb. recurve or longbow at around 180 fps.

Anybody want to speculate which one would get better penetration at any range?   :D  

Ron

[Jacko]

As I understand Ed's report he set about finding the threshold at which an arrow would reliably penatrate bone .

He also is looking for a way to explain why his research indicates lighter poundage bows are more efficient .

I am pretty sure the formula for working out the momentum of an arrow which is one of 13  indicators of arrow penatration performance is MOMENTUM = MASS X VELOCITY . That should indicate which of the above bows should deliver more momentum to an arrow

regards Jacko

[TomMcDonald]

Originally posted by Sharpster:
On the wheelie bow sites I have read many threads where the guys are constantly trying to attain "More speed and K.E.! More speed and K.E."!    :rolleyes:  

That's fine but, without also adding MASS, adding speed does very little to improve K.E.

I would like to see a penetration test between a 300 gr arrow shot from a 60 lb. wheel bow at 280 fps and a 600 grain arrow shot from a 45 lb. recurve or longbow at around 180 fps.

Anybody want to speculate which one would get better penetration at any range?    :D  

Ron

I'm crap at physics but doesn't KE come from a higher mass?

[Java Man]

Tom,

KE=Mass x (velocity) squared.  So velocity is king in calculating kentic Energy.  But KE is a poor predictor of penetration.

[EIGHTWGT]

Java,

I have read a LOT on this subject and am somewhat of a tech type person anyway, although Im not a physics major, nor engineer. I was interested in what Mr Ashby has found in relation to low poundage because he seems to have spent more time gathering this information than anyone I can remember reading about. Its another way to learn more... as we never stop learning no matter our experiance...

BTW - 8 wgt + Florida = bones, tarpon, reds....

[SteveB]

Ron,

What curve or longbow is getting 180fps with a 13.3 gr/lb arrow? I want one!

Steve

[bigiron]

SteveB; i'm with you , only i want one of each.

[O.L. Adcock]

Steve, pull one to 32 or 33" and you can get it!    At 30" I can get 160 at 14gpp.

RonD, Any bow gains or loses about 3-4% in horsepower for each inch up or down. A 40# at 28" should put out 9-12% more then a 40#@25". I say "should" cause there is enough difference between bows you can find good bows that will perform as well at 25" as poor ones at 28".

Blueline, good tuning goes without saying....

Before everyone goes off on tangents with this KE and mass thing...Keep in context what the Doc is looking at is how to optimize what ever bow is in your hand. In that context KE is a moot point, it's essentially fixed with little difference between 6gpp to 14. The ONLY thing a bow does is put KE into what ever arrow we stick into it...How we use that KE is what is important. It's like having a 500 horsepower engine sitting in your living room floor...We can make dragster 300mph in the quarter or we can drop it in a Kenworth and pull 80,000 pounds...A LOT slower...We all agree a 60 pound bow should be more powerful then a 40, it's because of more KE available.

Ron, Yep, the compound folks have a lot of false perceptions. They "think" they are optimizing KE with "fast/light" arrows. Truth is ALL bows work the same. Compounds get more efficient and have more KE as arrow mass goes up just like ours do. Their arrows would do more "work", as in cutting meat, if they'd slow them down with arrow mass, again, just like trad bows. Some say "speed kills"...Yep, with "fixed" KE speed (time) "kills" the amount of work that can be done....O.L.

[SteveB]

OL - I like my ear just where it is  

Steve

[carlr2s]

I was shooting a 27" CX 200 with 100gn head out of a 55lb compound and it way out penetrated my heavier aluminums. I think the increased speed and smaller diameter shaft is important.

[O.L. Adcock]

"I think the increased speed and smaller diameter shaft is important."...Yep, small diameter is WAY more important then the speed. Increase the weight internally til the speed was the same as the aluminums and you'd have something. Have you even read the Ashby reports?....O.L.

[George D. Stout]

carlr2s....I think you are correct sir.  We have not walked all of the streets and alleys as of yet.  Once that all is settled, we can discuss degrees of dead.