the momentum theory

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Griffo

#31 Post by Griffo » Sat Jan 24, 2004 9:06 am

I agree entirely Glenn, I loath the perpetuation of myths and total rubbish that permiate bowhunting and this probably is one of the biggest.

Griffo

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#32 Post by Stickbow Hunter » Sat Jan 24, 2004 3:52 pm

Glenn & Griffo,

With all due respect, I must say that I strongly disagree.

Glenn said:
I understand the momentum theory no worries, thats why I shoot 675 grain arrows out of my 47# hunting bow to get maxium penetration as have I said in a previous post. But to tell somebody that weight plus speed to get maxium penetration with your bowhunting setup is a myth because arrows flex all the way to the target reguardless of what you have been told they do not fly straight especially at hunting ranges. When you have things like archers paradox working against you especially at close range no amount of extra poundage or arrow weight is going to help you with penetration.
Glenn, you are not only contradicting yourself here but you are dismissing decades of proven scientific equations, and also bowhunting information gathered regarding arrow penetration. Arrow weight and velocity (speed as you say) is exactly what gives maximum arrow penetration with your bowhunting setup and it is NO MYTH!

In the simplest of terms - if an arrow isn’t moving it isn’t going to penetrate anything.

You mention Howard Hill, he used heavy arrows to give better penetration. When hunting big game he not only used heavier arrows but also higher poundage bows. Why? - To gain more velocity with the heavier arrows and therefore increase penetration. He could still shoot accurately with that heavier poundage though.
Your arrow setup must be perfectly matched to your bow so it will recover out of your bow as quickly as possible, if the arrow has still not recovered by the time it hits your target it will lose a lot of penetration. Even a very heavy arrow that has not recovered properly properly will not penetrate as far as a lighter arrow that has.
Your comments here are correct and I believe they have been supported not only in this thread but also down through the years of bowhunting.

I now want to comment on a couple of others things you have said in your posts.
I have seen women shooting bows as light as 35# taking boars, you just have to hit them right.
You don't need a heavy bow to shoot game, even the largest deer in Australia can be killed with a 40# bow as long as the correct arrow setup is being shot.
You may have seen women take boars with 35# bows. However, I believe that one should be careful in recommending this weight equipment for the taking of boars as no one could deny that this equipment, in regards to penetration, has little or no reserve if all does not go well.

You’re probably right about a 40# bow and the largest deer (Sambar), I don’t honestly know. One thing that must be remembered though is that they are a big animal and therefore as Dennis worded it, their bodies are somewhat denser through heavier musculature and bone mass. Once again I strongly believe that while it may be possible to take such an animal with a 40# bow I certainly wouldn’t recommend it because, as above, in regards to penetration, it has little or no reserve if all does not go well.

In both these cases I strongly believe that while it may be possible to kill them with the equipment stated when in the hands of a very experienced bowhunter - it could not be said to be probable with regards the average bowhunter.

Further to this - if a person can not say before he takes the shot that the probable outcome will be a quick humane kill, but only that it is possible that it will be - than the only ethical thing he can do is NOT shoot.

As a side note, in Victoria I think that there is a minimum legal bow weight requirement when hunting Sambar. I think it is 22.5kg (45lb). If this is the case, it shows that government departments have concerns as to the ability of bows and arrows to ensure a quick humane kill.

One last comment regarding the bow poundage comments above. I am not saying that a person should shoot a heavier bow if they can not shoot it accurately. What I am saying though, is that if they can’t shoot a bow accurately which is without a doubt of sufficient poundage to take the chosen game than they shouldn’t hunt that type of game.

There is no doubt that the subject of arrow penetration involves a lot of different things. These include; bow type, having the arrow matched to the bow, arrow balance point, broadhead choice and sharpness, etc. I think that it can be argued however, that the single biggest factor effecting the penetration of an arrow is its weight and velocity, meaning its momentum. Subsequently momentum alone can give you a very good indication of an arrows ability to penetrate.

Jeff

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#33 Post by russ » Sat Jan 24, 2004 8:00 pm

i have always pondered the idea of some trad hunting but always felt a bit skeptical of their performance on bulky shouldered boars bedded down at odd angles..now that i see that with heavy enough arrows i can get the performance i need, i sort of like the idea of doing some trad hunting on my next trip to the cape, and want to go the whole way with hand made arrows and a longbow rather than a recurve. i have never doubted the ability of my current gear but if i'm going to try something i know little of ,before i do a couple of quick questions..... generally speaking how long from tip 2 tip are most traditional longbows [when strung] compared to selfbows or recurves? and is a long bow or recurve more flexible in its ability to accuratley shoot arrows not necessessarily spined perfecty for it. i ask that because i will be hand planing my own shafts and have only ever made a couple of dozen.....and to maintain the power of a longbow, do you bother unstringing it during a hunt if u have to do a 2 hr drive to the other side of the property? and if you have hunted pigs[decent boars] with both recurves and longbows, have you ever thought that the longbow was lacking in its ability to deliver enough punch to do the job well when compared to a recurve?......keep in mind, though i have always been a compound user i have hunted mostly pigs at 10-15m and am very content to stalk close and only take comfortable shots with my trad setup..while there is bound to be a variety of opinions,i look fwd 2 all of them........russ

Glenn Newell

#34 Post by Glenn Newell » Sat Jan 24, 2004 11:10 pm

Go back and read my other post Jeff, and stop quoteing everything other poeple say and then saying that they are wrong or right , you seem to think that you know it all. Read what I said in the past that a simple formula for momentuim is not sufficent information for penetration with bowhunting equipment. Everything esle must be right to get the most out of your bowhunting setup. I am sticking to what I said that this formula by itself is a myth for bowhunting when all other factors are taken into consideration, or more correctly I should have said that it is only part of the story and not the whole story.
Its like a dog chasing it's tail here, Jeff you love qouting Howard Hill about his heavy bows and arrows and that was good for Howard he could shoot that equipment but the man also said that a 40# bow and a heavy enough arrow would kill a bull moose.
And also Jeff, I said that I have seen women shooting 35# bows take boars, this was not a recomendation to shoot boars with bows as light as that it was just an observation.
As I said I shoot heavy arrows, I shoot 675 grain arrows out of a 47# bow, thats a heavy arrow for that poundage, but as I also said I designed a longbow that could handle that weight arrow. Limb recovery is also another factor that will dictate the outcome of the arrows penetration.
That's why as I said on my origional post that the lighter bows were out penetraing the heavier bows on the targets, in short the lighter bows would have to had a much more efficent limb design and the equipment they were shooting was set up much better than the heavier bows, the result was that their momentuim must have been greater because the lighter bows were penetrating 100 millimeters and the heavy hunting bows were penetrating 25 millmeters, but according the momentum theory the heavy bows and arrows should have gone in further but they didn't, just an observation. Like I said take all factors into account and add them to the equasion and you will probably get a different answer.

Griffo

#35 Post by Griffo » Sat Jan 24, 2004 11:32 pm

Jeff, these are the main points of Glenn's post that I was in agreeance with.
Your arrow setup must be perfectly matched to your bow so it will recover out of your bow as quickly as possible, if the arrow has still not recovered by the time it hits your target it will lose a lot of penetration. Even a very heavy arrow that has not recovered properly properly will not penetrate as far as a lighter arrow that has.
Having your arrows matched to your bow is ESSENTIAL for a hunting set up. Isn't it the case that upon impact, movement in any direction OTHER THAN IN THE DIRECTION OF TRAVEL will cause a decrease in an arrows' ability to penetrate? So, if your gear is not tuned in correctly than you are hindering your ability to get good penetration on game.
The knowledge of tuning your arrow to your bow is one of the most misunderstood principles with traditionalist whereas with the hightec gear you can tune the bow to your arrows.
From my limited 'trad gear' experience, and from my readings of posts on this forum, I believe that this statement is quite accurate. How many people on here fully understand/understood archer's paradox, static spine and (I forget the exact correct term) kinetic spine, for example?
I feel sorry of a bowhunter when I hear them say that they can't shoot a heavy enough bow to shoot game like pigs, because some wanker has told them they need to shoot 60# for pigs, people who say things like this just don't know what they are talking about, ignorance and misunderstanding has been working against the traditional side of bowhunting for many years
This is one of the MOST perpetuated myths in bowhunting. Even just a few years ago when I seriously started hunting I had blokes saying, "gee fifty pounds hey?...you really need to go at least sixty to hit pigs etc with"... and mate, I tell ya, that's a load of crap and we all know it. If you match your arrows to your setup (now we're talking reasonable poundages here that most "blokes" would pull, not twenty pounds or thirty pounds) than you can hunt almost all the game in this country with no probs what so ever (maybe with the exception of tough hide game like scrubbers and buff).
In the simplest of terms - if an arrow isn’t moving it isn’t going to penetrate anything.
Mate, we're not pushing these in with our hands you know. ;)
You may have seen women take boars with 35# bows. However, I believe that one should be careful in recommending this weight equipment for the taking of boars as no one could deny that this equipment, in regards to penetration, has little or no reserve if all does not go well.
Any bowhunter with some experience would have reservations "recommending" that 35 pounds is a good pig hunting weight. I know Glenn is one of these.

I think that Glenn is pointing out that you don't need blistering speed to get good penetration and that you must also ensure that your bow/arrow set up is perfectly matched or the performance of your gear will suffer due to ineffecient energy transference and travel. Also that, when this is done, you can shoot lighter poundages and still achieve good results on game.

Griffo

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#36 Post by MarkP » Sun Jan 25, 2004 12:28 am

Russ,

As a rough guide many laminated longbows are in the 60-70 inch range. 62, 64 & 66 inches are all fairly common lengths. Selfbows can be just about any length depending on design. Laminated recurves are often in the 58-64 inch range, but this length is not the length along the string, its the measurement along the back of the bow. Hence a 64 inch longbow will have a longer string than a 64 inch recurve.

Longbows are usually more critical of arrow spine because they are normally less 'centre shot' than recurves.

Laminated bows can be left strung for very long periods of time with little or no loss of poundage. You really only need to worry about this if using a selfbow.

Neither bow is lacking with respect to the other - they are just different types of bows with various different characteristics. They both have their own idiosyncracies - and they are both wonderful to shoot !

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Mark

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#37 Post by Stickbow Hunter » Mon Jan 26, 2004 1:14 pm

Russ,

I think Mark P answered most of your questions but I will just add a couple of things.

Most laminiated longbows of the reflex or deflex/reflex design will perform very well compared to recurves although a well built recurve will IMO outperform a longbow but not buy a huge margin. A flat layed longbow will be lacking performance compared to the above mentioned longbow designs and also the recurves.

As Mark said, it is often quoted that longbows are more critical of arrow spine. To be honest I have not found this to be the case especially if you cant your bow when shooting. If you shoot your longbow as you would your compound, in the upright manner, spine can be more critical.

What is important, considering your shots will be taken from close range, is that your arrows are matched to your bow so that they straighten up as quickly as possible. As has been mentioned earlier, if they haven't straightened up when they hit your game their penetration will be hindered.

I have made quite a number of hand planed shafts. I find it best if you can get a block of suitable wood which has come from a large tree as opposed to a small diameter one. This way the shafts made from the block seem to be more consistant in spine weight.

If you have a shaft that is a little heavier in spine and you want to reduce the stiffness, sand it some more in the centre. This will reduce the spine but not have much effect on changing the mass weight of the shaft.

One more thing I thought of. I would not use the clip on nocks which you probably use on your compound arrows. The clip on ones tend to grip onto the string of the trad bows for too long and will not only slow the arrow down but can effect arrow flight considerably. You want a nock that will just hold the arrow onto the string when you put it in a vertical position but will release when you tap the string.

All the best with getting everything together and if you can, please post some photos of your arrows and bow. All the best with the hunt also.

Jeff

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#38 Post by russ » Mon Jan 26, 2004 1:30 pm

thanks mark and jeff, good points i will consider.......russ

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#39 Post by Guest » Mon Jan 26, 2004 5:28 pm

This thread looks like fun.....not!!!
Actually it makes my head spin :( I thought the attraction of trad bowhunting was it's simplicity.......

G'day Russ,
Your questions seem to be covered, I’d just like to add a couple of things.
The ability of a bow to handle a range of arrows, some a touch stiff-some a touch weak, will be mostly (I know that there are other factors) a result of it's degree-of-centershot.

I once had a fella say that with his true centershot bow he was getting seriously improved penetration on boars at close range - 3 to 6,7 meters, something he had been having a little trouble with for a while. Sounds close I know but I have been there myself, actually had to lean back to get room to take the shot.

The question, which is better? Longbow, Recurve or even Selfbow for that mater, is not that relevant in the bush in my view, it has far more to do with how you use and your ability to use your chosen bow.

I may have been doing it wrong all this time Mark P. but to my knowledge you measure longbows nock to nock across the back of the bow but not recurves.

With my recurves (and every other, production and custom that I've checked) the bow length is given as a measurement from nock to nock around the belly of the "unstrung" bow. The string length that this gives you will vary according to the design of the bow but an example with one of my bows..... a 62" recurve giving you a string length of about 58 3/4".

I thought that that was a "given" but would like to hear it verified from others in the know out there, thanks.

Mark K.

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#40 Post by Dennis La Varenne » Thu Jan 29, 2004 11:19 am

Hooray again all –

I have been revisiting this thread since Russ’ original question, and a few things are very apparent in the way this topic was discussed. The same thing often occurs with others too.

Could I remind everyone that the original reason for this post was to help explain to Russ WHY momentum is a better indicator of the ability of arrows to achieve lethal penetration on game than kinetic energy because of certain inherent properties discussed on this thread.

We seem to have lost sight of that purpose and have introduced a lot of material which is properly the subject of another post.

It is not that the subjects are not important in themselves. It is just that we allow ourselves to go off at tangents all the time, and our debates become bogged down in unrelated subjects which do not advance discussion on the original topic. We sometimes fall into personal insult and adverse innuendo about each other’s competence which we ought to be above.

Everyone has the right to robustly put a position or counter argument and should do so to the best of their ability so long as it is pertinent to the original topic under discussion and is not any form of personal attack or ridicule.

For instance, Woody has a problem when I use analogies, but that is not a personal attack of any sort. He argues the issue, not the person.

(In my defence, I believe analogy to be a powerful and valuable teaching tool and my purpose in using them is to explain a point. They are not the point or the argument itself nor are they a comparison - they are another way of explaining the same thing for the benefit of readers’ better understanding. Most importantly, I ALWAYS come back to the topic of discussion itself with my use of analogy and try to demonstrate its relevance to the issue.)

Glenn Newell has raised a lot of important discussion points about archery equipment set-up, but neither are they relevant to the discussion of Russ’ original question.

He did not ask what equipment set-up he should use, or what was the best. He is clearly a very competent bowhunter himself and doesn’t need to learn to suck eggs. He did not ask to be informed whether light gear was as good as heavy gear or whether heavy arrows were superior to light arrows or any other of the myriad of issues which have been raised in this post.

He only wanted to know something about one aspect archery ballistics and why it was advocated over another.

Thus far, no-one has really raised an objection to my advocacy of the use of momentum as a preferred means of predicting arrow penetration where appropriate equipment set-up is a given. Appropriate equipment is another important debate entirely, to which Ed Ashby has contributed a considerable amount and is properly the subject of another post – not this one.

Irrespective of the gear we choose to use, the question was – do we use momentum or kinetic energy as the best indicator of whether or not we will obtain reliably humane lethal penetration on game animals?

We could go on for ever arguing among ourselves about the above, but could I ask the readers to take the time to think about what they post before they post it and not simply react to what they think is being said or inferred before they have read the whole post.

If you think something controversial is being said either against your own argument or another’s, cool off for an hour or two and think about what you have read before you reply.

Please also be open to the idea that someone who opposes you just may well have a valid point anyway. That doesn’t mean that you have to go along with everything they post, or that you have forfeited the right of reply where you disagree.

In essence, I am making an appeal to common decency and fairness in debate. So please, could we –

1. Keep it relevant and to the point of the original topic;
2. Leave out the insults or ridicule;
3. Back up our arguments with references as much as possible;
4. State personal opinion as such; and
5. If a separate topic is introduced, show where it is directly relevant to the original, or start a new thread;
6. If personal experience is cited in an argument, especially in respect of equipment performance, please give specific and as detailed examples as possible – the more the better.

Over to you all,

Dennis La Varenne
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#41 Post by erron » Thu Jan 29, 2004 12:27 pm

Dennis,

I wholeheartedly support your appeal for decency and fairness in debate.

We really must strive to make this the best place for exchanging ideas that we possibly can, and the issue always revolves around respect for others, even when we disagree with what they say, or it pushes our buttons for some reason.

As a moderator, I especially take on board your plea to ‘or start a new thread’. Folks, if you think a thread needs to be split, either have a bash at it if you’re a moderator, or contact one of us to get it done.

Thanks all,

Erron

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