Arrows for big boars?

[Wellsy]

Going to the Cape shortly and was wondering how heavy I should get my arrows?
I shoot a compound at 64lbs and my current arrows are 450 grains and and leave the bow around 255 fps.
Should I increase the arrows to around 550 grains?

Wellsy

[jpbon]

Here's a link to a kinetic energy calculator. You can work out the best hitting power at both weights.

http://www.bowhuntinginfo.com/KineticEnergyNew.htm

[Wellsy]

By my calcs I would currently get about 65ft/lbs, if I add 100grains to the arrow I lose about 25 fps and the kinetic energy stays the same?
Wouldn't I be better to leave it as is and have smaller pin gaps?

[jpbon]

Why would you have smaller pin gaps if left as it is?

[Wellsy]

Heavier arrow/less speed/more drop over distance= bigger pin gaps :wink:

[FentonW]

Kenetic energy means **** to a bowhunter, momentum is where it is at. Its simple, the heavier it is the more force it takes to stop it. Eg Truck travelling at sixty verses a car doing the same speed, the truck is going to get a lot further after it hits something before it pulls up. Putting that aside keep your arrows above 500-550gns, I have hunted the Cape for a long time now and big mature boars will eat up light stuff and throw it back at you. Send Mick a PM he has been hunting up there a long time also and has seen an awful lot of differant arrow weights used, the more you see in action the more someone can comment on it.
Cheers, Fenton.

[jindydiver]

By my calcs I would currently get about 65ft/lbs, if I add 100grains to the arrow I lose about 25 fps and the kinetic energy stays the same?
Wouldn't I be better to leave it as is and have smaller pin gaps?

Not if you believe that momentum is as important as KI (as I do).

Over the distances you normally shoot at would 25fps make more than a small difference to your sights?

[Glenn]

I would be going for the heavier arrow and calculate what the momentum would be, that's a better indicator for penetration of an arrow. You will loose speed but the momentum should be higher...Glenn...

[Wellsy]

What's the difference between kinetic energy and momentum?

[Glenn]

Kinetic energy is a good indicator for the efficiency of the bow but as Fenton pointed out momentum is the indicator for how efficient an arrows is. The heavier the arrow the more resistance is needed to pull it up. A heavy slower arrow arrow will out penetrate a faster lighter arrow.
I think the Cape boars are more heavily built I would definitely go for the heavy arrows, if I were you Wellsy I would stick to 10 grains per pound for hunting the Cape boars...Glenn...

[jindydiver]

What's the difference between kinetic energy and momentum?

From my fav' encyclopedia

The distinction between them can be seen in the action of a pile driver. The distance to which the pile is driven depends upon its kinetic energy; the length of time required for the action to cease, upon its momentum.

In physics, the property or tendency of a moving object to continue moving.

This equals, in bowhunting, penetration.

[Luke]

I have six dead boars from Bowcomp (where you're off to isn't it Wellsy?)to testify that 460 grn carbons from my Hoyt Cybertec @ 29 inches and 70 pounds is quiet effective. ;)

Having said that, the heavier the better the penetration, absolutely.

I found my set up to be adequate but some extra weight for insurance can't go astray.

I was not interested in knowing the weight of my arrows but it was that Bazza had his digi gr scales there so I whacked them on. I figure, they fly great out of my bow, I know they will drop a boar well so why muck around changing it?

Just my thoughts.

Luke

[woody]

Wellsy,
I would say that your current set up is adequate in my opinion. More relevant is shot placement, style of broadhead ( cut on contact style) and broadhead sharpness.

If your accurate and well tuned with your current set up I cant see much value in fiddling with your gear, if it aint broke, dont "fix " it. :D

[Trophy Bowhunts]

If you are comfortable with your setup and are shooting well then whatever you use will do the job...

BUT

If you havn't hunted the Hogs up the Cape or Gulf I suggest that you use the heavest arrows you bow will shoot comfortably and also with what you are comfortable shooting...As Fenton said.. they have a lot of life in them and they don't like dying. A heavier arrow makes a whole lot of difference in stopping them. The comment I get every trip is how can these hogs carry such good shots (Its called survival), If you have to fight to stay alive all you life you don't give up easily...


So I suggest a arrow of at least 600gn will not let you down when you need that bit of insurance...plus a good strong broadhead and must be Razor sharp.

Mick

[Wellsy]

Today I tried some coax cable inside my 65/80 whitetails to increase the weight of my arrows, without scales it is hard to say but I'm guessing they would be around 600 grains.
I first shot my standard arrows (450 grains) from 20mtrs then the weighted arrows.
The heavier arrows hit about 300mm below my standard arrows. (20mtr pin v's 40mtr pin). I couldn't notice any extra penetration on the bail....
I then set up a 3d dog which hasn't been shot (exception being beman flash arrows from a 20lb bow, about 20) to see if penetration could be noticed?

This is the result
http://img.photobucket.com/albums/v713/wellsyinoz/arrow1.jpghttp://img.photobucket.com/albums/v713/wellsyinoz/arrow2.jpg
Blue and white vanes are weighted, orange and black are 450 grains.
The vanes on the weighted arrows are lower so maybe I need a heavier tip(currently 125 grains), but I can't say that any extra penetration has been achieved.
What do you guys think?

Wellsy

[FentonW]

Targets aren't real animals, there are a lot of things that come into play when it comes to penetration on heavy animals. Like I said send Mick a PM, I would at a quick count up have seen over 400 Mature Cape york boars shot over the last decade or more and I would think Mick would have seen a hell of a lot more than that. Nothing beats pure numbers for a comparison. i remember Mick telling us on a few occasions that light carbons just don't cut it on those big boars. I have hunted a lot of pigs out west as well and they are not the same beast as those fellas up there. But opinions are just that, if you are confident that your set up will do it's job than go up there and wack the bejebus out of them. My personal steups over the years have been;- 65-70# recurves and longbows shooting 580 to 650gn arrows and now it is a 70# Tribute with 550 gn arrows. I figured if I set up my gear for those bad boys it will handle anything I can throw at it, and to date it has.
Cheers, Fenton.

[Wellsy]

if you are confident that your set up will do it's job than go up there and wack the bejebus out of them.
FentonW,
I'm not confident, that's why I'm asking the questions?

[Wareagle]

On 3D targets, light fast arrows seem to have more penetration, cause more friction, and bloody hard to pull out. I have never shot anything big with a bow, so I keep an open mind.

[Glenn]

Foam targets and animals are too different things and should never be compared. When you are making arrows, if you are going to add weight it makes a big difference where you put that weight, that's why I only use wood shafts because I can hand taper them and get the weight exactly where I want it to have the greatest effect and not upset the dynamics of the arrow...Glenn...

[jindydiver]

Foam targets are designed to pull up arrows, whereas animals aren’t.

Maybe you need to get out and chase some goats or something so you can see for yourself what difference it is making.

[woody]

Wasn't there an article in the last issue of Bowhunting Down Under magazine, where a lady bowhunter put quite a few big boars down.

What were the particulars of her equipment set up?

It seems to me, that everyone focuses on bow weight and arrow weight, when there is a lot more factors involved in what works and what doesn't.

A 70 lb longbow will probably throw 650 grain arrow somewhere around 180 feet per second. give or take 5 feet /sec.

This gives 46.78 ft/lbs of kinetic energy.

700 grains at 180 ft per sec = 50.37 ft/lbs of kinetic enegy.

800 grains at 180 ft per sec = 57.57 ft/ lbs of kinetic energy.

The above examples completely ignores the fact that the heavier the arrow is, the slower the velocity will be.

The original question was, if a compound bow of 65 lbs and arrow travelling at 250 feet per sec was producing enough grunt to handle big boars. It was producing 62.47 ft/lbs of kinetic energy.

I agree that heavy arrows give an advantage out of slower bows, but I dont consider 250 f/s slow :D

[Glenn]

Here are some exerts from an article about selfbows and arrows Dean Torges wrote a few years ago, there is some info here about a test Fred Bear did back in 1943 about the impact of arrows...Glenn...


Matching Bows to Arrows
©Dean Torges/The Bowyer's Edge™
The importance of matching arrows to bows has so focused some of us that when sorting arrows into spine and weight groups we go well beyond our skill as archers to perceive differences and perhaps even beyond our equipment’s ability to appreciate our efforts. I don't dispute the importance of arrow spine. But we may be better served by first selecting our arrows to our purpose and then finding or making bows to match them.

Because their emphasis lay with field archery, their preferences ran to lightweight tackle that eased the physical demands required of protracted shooting at the butts. Draw weights decreased even further during this period as the development of more efficient target bows provided increased cast, thereby permitting lighter bows without sacrificing performance. Interestingly, these events were paralleled by tackle manufacturers who, through the sale of light equipment, began wooing gun hunters to participate in archery seasons. These part-time archers further increased the demand for lightweight bows.

Fred, and Howard, Too

In 1943, in an article entitled "Hunting Arrows" published in Ye Sylvan Archer, Fred Bear noted that "the growing popularity of field archery" has "created a demand for light weight, fast arrows." He warned against assuming "that the same qualifications are proper for hunting."

Mr. Bear conducted experiments through a shooting machine with six variously weighted arrows (300-800 grains), each in turn shot through six variously weighted bows (45-68 lbs) to prove his thesis that we should shoot heavy arrows (approximately 10 grains per pound of bow weight) through heavy bows (no less than 60 pounds at full draw for an animal the size of deer). The bows ran a sampling of limb design and materials, some backed, some not, some recurved, some straight, of hickory, yew and osage in various combinations and lengths.

The importance of arrow weight and its impact upon penetration stemmed from his observation that complete pass-through penetration of mortal arrows usually killed humanely and quickly, often near the archer, whereas mortal arrows that stayed within game often caused frightened flight, poor blood trails and, occasionally, even lost game, even when the broadhead exited the opposite side.

Using both a shooting machine and an impact measuring device (a bob, suspended pendulum fashion, that recorded the impact of each arrow with a stylus), Mr. Bear found that on the average "the 400 grain arrow struck 20 per cent harder than the 300 grain, the 500 45 percent, the 600 66 per cent, the 700 82 percent, the 800 100 percent."

He noted also that a 500 grain arrow shot from a 61 pound bow struck with a force within 1 per cent of a 600 grain arrow shot from a 45 pound bow. From the other direction, a 68 pound bow with a 500 grain arrow struck less than 3 percent harder than a 52 pound bow with a 600 grain arrow.

Just as some bows are more stable and forgiving than others, and therefore preferable as hunting weapons, Mr. Bear observed that heavy arrows provide the hunter a margin for error by minimizing mistakes of form likely experienced in less than ideal hunting situations. He observed that heavy arrows, averaging ten grains per pound of draw weight, were "less sensitive to correct loose and form" than lighter arrows, which he labeled comparatively "inaccurate" and "unstable" under hunting conditions.

The implications of all this to the hunting archer? In Hunting the Hard Way, Howard Hill maintained that “all else being equal, penetration is the name of the game.” To my mind and preference, this translates to sturdy two blade broadheads at the end of heavy arrows that don't deflect easily from course, shot from quiet, sympathetic bows with the objective being complete pass-through penetration of vital areas on big game animals. If we don’t always achieve this objective, it should still shape our equipment choices, as well as determine our shot selection, because our quarry’s death is not our only goal.

More Bows

We have available to us today a vast array of arrow shafting to choose from, and a vast array of bows to match up with them. We've done nothing more here than reconsider the importance of arrow weight and generalize upon limb design. But we can leave with enough information to map strategies based upon individual preference and purpose. With his own circumstance in mind, an archer can search out the arrow to his needs and then purchase or make the bow styled to maximize that arrow's performance under the conditions of its use, and thereafter tune the arrow to the bow.

Hunting archers must guard against the current trend toward lighter bows without making compensatory changes in arrow weight. Recreational target archers should not feel underpowered pulling light bows, fearful for lost cast, because limb profiles, possible through the lamination of diverse materials, have brought us exceedingly efficient bows to couple with light arrows. And those who wish a multi-purpose bow and arrow combination can find a market place willing and able to meet their needs.

[aussiehunter]

yes woody and i wrote the articale :)

40lb mathews mustang,gts 600 pros shafts tipped with 115 razor sharp blackstumps,plus inserts giving a good heavy 145g total arrow head weight.

shots were kept under 25 metres,good shot placement resulted in most pass throughs ansd quick clean kills

im with fenton,i prefer good weight,with good foc and a good razor sharp head like woodys or blackstumps

but u cant beat good shot placement, and know ur animals vitals ,its when ur shot may be a bit off etc,that good arrow weight will prove itself along with a well made broadhead

jmho


pat :)

[woody]

Pat ,
What would the total arrow weight have been ? :D

Glen,
I'm not disagreeing about arrow weight being a consideration, but Fred Bear was not testing hard cam compounds..... and the question was if a 65 lb compound shooting 450 grain arrows at 250 feet per second was adequate for big boars.

In my opinion, it will do the job fine. It is probably producing as good or better impact energy as a 70 lb longbow shooting 700 grain arrows.

Accurate shot placement and sharp cut on contact broadheads would be my only other recommendation.


I have also a lot of time for Ed Ashbys broadhead and arrow weight studies, and if Buffaloe was the target animal, I would defineately be using arrows 750 grains or better.

I dont consider pigs as big game, their getting up there, but unless you are shooting relatively slow bows, like recurves and longbows, super heavy arrows are not really nescessary.


I'm not bashing trad gear either, I own 7 Bear recurves and have been known to take them bush now and then. :D


Fred Bear and Howard Hill were both legends, and I have the greatest respect for their memory, but I suspect they would be impressed with how hard the modern compounds can fling arrows. :D

[rohan]

i agree with jindy, get out and whack a few goats with different arrows and see the results.
rohan

[Wellsy]

My bow with 450 grain arrows has no problems with goats(never not had a complete pass through, including a couple of shoulders).

I know heavy is definately better, the yanks at the moment seem to have a need for speed and are useing what I consider super light arrows(350 grains, 300fps) for deer, but at some stage too heavy must have a negative effect. This can be seen in kinetic energy calcs and I understand momentum is more important but at what point does too heavy become a problem?

[Glenn]

You're right Wellsy there is a point where weight becomes negative but you are well within those limits, I shoot a 45# longbow and I shoot 670 grain arrows on pigs that's around 15 grains per pound, at my average shooting range 11 meters and under drop is not a problem...Glenn...