Do smaller diameter arrow shafts such as Axis or FMJ really get better penetration than normal size carbon shafts or aluminum shafts or is it just Easton marketing? If smaller diameter shafts do get better penetration where are Easton's competitors?
Assuming that you are talking about through animals, they probably do, however, no one has ever shown me any data to prove it. I believe any real differences are so small as to be unlikely to be easily measureable.
When one thinks about it, for example using a BH that has a 1" plus cutting diameter...arrow diameter IMO isn't really going to make a difference. The long of it is...I agree with Spike Bull...haven't seen data to prove it.
Trophy Ridge should be a top competitor! Thats what I just changed to. They have a insert outsert that is indestructable! I just shot on into a brick wall at 20 yds. Unscrewed the field tip cause it was stuck. Put a new one in and it shot just fine! But yes smaller shaft less friction and drag! Firm beleiver! Mathews S2 73# draw weight, 29" draw, around 68# of kenetics.
chuck adams used to say a while back that arrow diameter has no affect on penetration because the animal lubricates the arrow with blood and any other organs and also if the broadhead shaft if the same size as he arrow or a little bigger then it creates a channel for the arrow to go thru with minumal drag. i think he wont make that claim now tho. i dont see the difference between an easton axis vs a gold tip shaft making a signifigant difference in an animal. targets are different because a bigger shaft has more friction surface.
Joehunter8301, That makes sense. Less surface area on the arrow as it passes through would decrease drag and would be less likely to slow down the broadhead, even if we are talking milimeters, however, milimeters might be the differnece between a freezer full of meat and an unfilled tag.
I see the logic of less friction surface equaling less drag meaning better penetration. However, getting the arrow to its intended target is of paramount importance. If you can find a smaller diameter arrow with the correct spine and it flies well out of your setup then small is good, but I would never sacrifice ANY good flight characteristics for penetration. Flight first, then penetration. IMHO
Theoretically a smaller diameter arrow will have less drag and therefore less penetration. However, surface area of the tubing has nothing to due with friction.
Friction equals the coefficient of friction of the mating surface materials involved times the force perpendicular to the surface.
Drag due to surface adhesion would be dependent upon surface area. and would give a slight advantage to the skinnier or shorter arrow.
Frontal drag would probably be the main reason for a skinny arrow out performing a larger one. Drag=1/2 p V^2 C A with "A" being the frontal area. Less drag at the rear of a skinny arrow would also be a factor.
The skinnier arrow would not only arrive at a faster velocity ( thus having more KE), but it would also lose less velocity as it passed through any material that acted as a fluid.
Now back to the real world. When you put the same broadhead on both a skinny and a fat arrow, they would both have the same frontal area and therefore the same drag. The difference in penetration would be miniscule.
That first sentence should read MORE penetration.
I thought they were saying that because thier arrows weigh more per inch than say the gold tips do...
Lets say you are shooting 2 blade BH and the arrow splits a rib or a shoulder blade on a deer. After the BH goes through it the bone wants to pinch the arrow shaft. A skinnier shaft should have less friction therefore increasing penetration. That was my thinking.
Just for the sake of something to think about::::
What happens when you cut tissue? The wound opens up! Right? So therefore, there shouldn't be all that much drag on the shaft in the first place.
Don't know anything about all the scientific jargon or any studies that try to prove it one way or the other. All I know is that I never had a pass through on an elk when I shot aluminum. Since I switched to smaller diameter carbons, only one hasn't been a pass through and that was a petty tight quartering shot. The aluminums weighed more than the carbons I used to use (I've since switched to FMJ's) and I pulled 72 lbs then vs 65 now. I think the results are more than just coincidence.
I agree with WW. Think about it this way. The next time you shoot a deer, take a skinny shaft and a fatter shaft and push both through the hole in the deer with no broadhead attached. Both should go through with little to no effort required because the hole the broadhead made is MUCH larger than any arrow shaft. The shaft simply follows the hole the broadhead cuts and it's weight adds to the momentum that drives the broadhead forward.
The skinny arrow concept IMHO is just a big marketing gimmick by Easton. They base everything on the fact that skinny arrows of equal weights penetrate better than larger diameter shafts with FPs, which of course is true because of less drag. That concept is useless when you put a broadhead on the end which cuts a larger hole than any shaft out there.
Easton also claims their HIT insert system "automatically aligns broadheads to the shaft". The dozen Axis shafts I bought were the worst spinning arrows I've ever tested with significant wobble in 7 of the 12. There's a reason nobody is copying their designs and I'd look elsewhere for a hunting arrow.
Axis penetrates my target much deeper than carbon express. Never noticed a difference on deer unless I used a Rage. Even on TV the rages usually don't penetrate anywhere near through and through.
I've used Axis for years and doubt there is any advantage in penetration due to small dia
I use the FMJ's because they are heavy and durable. I have received excellent penetration with them on large, dense boned game species but I cannot tell you whether it is the weight, the diameter or both that account for this fact. This is all academic in the event you primarily hunt whitetail or most of our NA deer species. It becomes a significantly bigger deal in the event you actually need the penetration advantages slim shafting offers. In that situation, every potential advantage is worth trying.
your argument just may be right i you are using a big BH, however, if you to the Trophy Ridge website and see their testing, yu will see that they are using an arrow that is smaller in diameterwith a field point they are both the same diameter, there-fore proving that the smaller he diameter the more penetration, in fact they clai,m that their arrows have up to 27% greater penetration than any other, and that is with a fild point, check it out very one
sorry aboutthe gramer of my last post, my keyboard is a bit worn out, i need a new one
Of course you get better penetration with field points, I already said that. Stick a sharpened broomstick and a pencil into a target and see which is easier. Then put the same size broadhead on each and try again. There will be no difference.
What TimBow said. I very seldom get less than pass through with 2219 alum. arrows - the BH cuts a big hold and the drag is almost nothing.
Scotty I believe is spot on. A straight flying arrow is the most important thing. I know this thread is on shaft diameter and penetration.
I currently use a 65#@31" recurve and shoot 2216 and 75/95 GT Traditionals all with 3bld Muzzy BH. I see no difference in penetration between carbon and aluminum. They all blow through the animals. I'm only going by my experience with elk, deer and bison. I also saw no differnce when I was shooting 2514 poles compared to carbon from my old 85# PSE Fireflite.
Someone above stated never attaining complete penetration on elk while using aluminum arrows. I find this amazing and question if those arrows were flying straight. How can many hunters using lighter weight bows attain complete penetration while others with much heavier rigs fail. I think of arrow flight as the number one reason.
I never have bought into the so called theory. When you cut a hole 1+" with a bh, the shaft diameter shouldn't really come into the equation unless it exceeds the diameter of the bh. The shaft would be passing through flaps of tissue. UNLESS of course you shoot field points into big game. THEN, I'd say the diameter would be relative.
"Someone above stated never attaining complete penetration on elk while using aluminum arrows. I find this amazing and question if those arrows were flying straight."
Simple answer to your question. Yes, they were flying straight. All I know is I have had better penetration with carbons. As for the reason, don't know and don't care.
Wyo, I don't know you but I've seen 55# bows blow through elk and you were shooting a 72# bow and falling short. There is a problem and it ain't the aluminum. That arrow couldn't be flying straight or if it was you were hitting something very solid. I'm glad your current setup is performing like a bow should. Keep the faith!
I have seen a difference in obtaining more passthroughs after switching to the thinner carbon from the larger aluminum, but like others have stated, I'm really not sure why.
I will say that one big advantage is shooting in a significant crosswind. The smaller carbons drift far less than the fat shafts.
I also like the fact that they are quieter.
Dreamcatcher...evidently you do know me since you must have been standing next to me and observing all the elk that I shot with aluminum arrows. It's amazing how the Internet has allowed some people to analyze other's experiences with such authority.
I have a short draw length. Back when I shot aluminums, technology was nowhere near what it is now. Short draw length equaled slow bow. I was lucky to get 235 fps. My KE was around 50-52 ft lbs. Last elk I shot with aluminums was 22 yds broadside, leg forward. Didn't hit rib and penetration was only to the fletch. I was, and still am, a perfectionist as far as tuning my bow, so I hate to burst your bubble, but yes, my arrow was flying straight.
Fast forward to the following year. Same bow, same everything, except I had switched to carbons. Elk was 25 yds, slightly quartering away. Hit rib going in, hit rib going out. Arrow was laying 10 yds from where it went through him.
I responded to the original question based on my experiences. They are based on fact, not speculation. After all, I should know. I was actually there.
Wyo, I'm responding from what I experienced over my 30 years of hunting too. No, I wasn't next to you but you sound like a real peach to hunt with.
What you say/type makes no sense to me. I say this because I have a buddy that is able to blow through elk with his 60# bow and 26" draw using aluminum. Funny, he uses carbon now but never had an issue with aluminum. He states the carbon are more durable and that was why he switched. Perhaps the elk your hitting are bigger than the ones we get in NW Montana.
As you stated, the aluminum arrows were heavier than the carbon. Speed does not kill and the increase in momentum you attained with the aluminum compared to the carbon should IMHO have caused that short arrow of yours to blow through the animal. This is with the same BH.
The number one reason for lack of penetration is poor arrows flight. I know everyone has perfectly flying arrows as you also stated. This is not the case from what I've seen over the years even with so-called veteran hunters.
From my experience, carbon arrows are easier to tune and are more forgiving than aluminum. The deeper penetration is a direct result. Now your arrow is truly flying straight like it should have been with a properly tuned aluminum shaft. The slight decrease in diameter thickness is certainly not the reason for increased penetration. The simple and very logical excuse is poor arrow flight and some are just to ignorant to realize.
So you can tell me what you experienced and I will tell you, simple physics don't lie. I don't have to be there next to you to realize what you were claiming went against everything taught to me in school many years ago.
I used to shoot 2514 logs for many years and it was never an issue. And those are about as big as they get. Admittedly only one elk with those shafts, but a good many deer and pigs.
Through flesh and blood I saw no problem, never an issue. Never really noticed much when I switched to carbon penetration wise either. The carbon arrow was a bit lighter, but went faster. But not by too much.
In theory I believe diameter may come into play going through bone or cartilage as the cut the broadhead makes doesn't give the clearance flesh does, nor the lubrication.
All else being equal as to weight and tuning, I wouldn't give the nod to one or the other WRT penetration. If it's not a total "non-issue" it's close enough to it for me.
I would imagine regular size shaft compared to the ultra thin shafts would be about the same. Maybe if you go from the 2514 and down to an Axis you may notice? But I'd doubt it. Sure wouldn't be what I based my selection on.
TD, I also used the 2514's and never noticed a difference either!
I have a brother living on Or. that hunts Elk and bear with a 61# recurve and 29" draw. I just got done talking to him on phone, he has no computer. He uses Alum. arrows on both animals, XX75 2216's - he clames to get complete pass through on about six of seven animals. He uses the same BH I do, the old snuffer three blade COC. If they are super sharp and your shot is true, you have a dead animal, pass through or not.
If the diameter of the shaft matters enough to even discuss, your penetration problems began way before you released the arrow.
Slow motion footage of the different shaft materials tell us why the skinny carbon arrows penetrate better.
Dream Catcher...PM sent