Arrow/broadhead deflections?

[Ridgerunner7]

I recently shot a buck perfectly broadside slightly behind the front leg. Arrow sign and blood trail indicated that it exited far back through the guts. I was using a Killzone 2" mechanical. This is the second time I believe I had some major directional change once the arrow entered a deer's body with this broadhead.

Have you guys ever experienced this? I've heard about it but haven't heard many first hand experiences. So what causes it? Here's a interesting video of what I'm referring to.
http://youtu.be/um2Sa20KTGE

[ Post made via iPhone ]

[JakeJD]

I have had a couple deflections like you are referring to - solid broadside shots that entered in the chest and exited through the guts / back legs. Both were confirmed with recovered deer / autopsy.

I assume my head must have just hit a rib perfect and deflected once in the body cavity?

I believe I was shooting Slick Trick mags with both...

[cbigbear]

I recently shot a buck perfectly broadside slightly behind the front leg. Arrow sign and blood trail indicated that it exited far back through the guts. I was using a Killzone 2" mechanical. This is the second time I believe I had some major directional change once the arrow entered a deer's body with this broadhead.

Have you guys ever experienced this? I've heard about it but haven't heard many first hand experiences. So what causes it? Here's a interesting video of what I'm referring to.
http://youtu.be/um2Sa20KTGE

[ Post made via iPhone ]

Purely a guess, but I'm thinking the deflection is caused by one blade opening & catching a rib/bone while the other is still closed or not open to the same angle yet.

[stash59]

Here's an interesting viewpoint!

https://www.youtube.com/watch?v=rVv7QAQZ45A

[JoeRE]

Good topic. I have experienced something similar a couple times. In 2006 I shot a nice buck, slight down angle at 18 yards, the arrow deflected up a rib and miraculously had enough power to damage the spine and put him down. In the photo the arrow made contact with the rib right at the start of the split from the outside and slid up.



In 2007 I shot another buck slightly quartering to me. The arrow hit a rib and deflected back, sort of the opposite of what was in that video. It ended up being a lethal raking shot but not pretty and if you just looked at the wound channel a person would say the deer had been almost straight on. I know that was not the case and it was a close shot, the deer did not jump the string much if at all.

In both these cases I was using crappy broadheads with weak ferrules. Both ferrules bent badly I think just from the initial impact on hard old buck ribs. They were the old Wasp snaplock broadheads. As the ferrule bent that steered the arrow to deflect.

I have never had a major deflection with a muzzy, slick trick, mangus, or any other quality, rugged head. With some expandable broadheads, weak ferrules might be an issue too but also forward opening blades causing it to skip?

I have been on a couple trailing jobs where I SUSPECTED the arrow slid up under the shoulder like on the video but never confirmed it as we never recovered the deer.

In my opinion, a lot of quartering away "1 lung shots" are actually arrows that do exactly what is shown in the video and never punch the chest cavity.

[MOBIGBUCKS]

Only time I've seen it is with light arrow setups. I shot a 161" back in 2010 at 32 yards and drilled him quartering away and the arrow broke trying to change its course. After that I beefed up my setups with mechanicals; I tune my bows to shoot a spine size heavier just for the added weight and stability (something I love about two track Binary cam bows--easy to tune an arrow with different spines within reason of course)

[JoeRE]

MOBIGBUCKS made me think of one other thing. He mentioned light arrows...the only time I have seen it were in light arrows with pretty [glow=red]low forward of center (FOC)[/glow] as well.

The more momentum you have the harder it is to change the direction of an arrow. Period.

[Ridgerunner7]

I recently shot a buck perfectly broadside slightly behind the front leg. Arrow sign and blood trail indicated that it exited far back through the guts. I was using a Killzone 2" mechanical. This is the second time I believe I had some major directional change once the arrow entered a deer's body with this broadhead.

Have you guys ever experienced this? I've heard about it but haven't heard many first hand experiences. So what causes it? Here's a interesting video of what I'm referring to.
http://youtu.be/um2Sa20KTGE

[ Post made via iPhone ]

Purely a guess, but I'm thinking the deflection is caused by one blade opening & catching a rib/bone while the other is still closed or not open to the same angle yet.

Yeah, I forgot to mention my last buck has a clear mark on a rib on entrance side. My arrows aren't lite but not super heavy either. 422 gr at 70lbs and 29.5" draw.

[ Post made via iPhone ]

[rancid crabtree]

I watched that video with the “Moses” buck. That was wild. I don’t think I recall him mentioning what broadhead he used. Was it a Mech???

This is why I shoot a heavy setup with lots of FOC (I even use brass inserts instead of aluminum) and I tune the out of my bowhunting rig for good broadhead flight out to 70 yards.

[Ridgerunner7]

I watched that video with the “Moses” buck. That was wild. I don’t think I recall him mentioning what broadhead he used. Was it a Mech???

This is why I shoot a heavy setup with lots of FOC (I even use brass inserts instead of aluminum) and I tune the out of my bowhunting rig for good broadhead flight out to 70 yards.

I remember the show. He was using a mechanical.

[ Post made via iPhone ]

[MOBIGBUCKS]

I recently shot a buck perfectly broadside slightly behind the front leg. Arrow sign and blood trail indicated that it exited far back through the guts. I was using a Killzone 2" mechanical. This is the second time I believe I had some major directional change once the arrow entered a deer's body with this broadhead.

Have you guys ever experienced this? I've heard about it but haven't heard many first hand experiences. So what causes it? Here's a interesting video of what I'm referring to.
http://youtu.be/um2Sa20KTGE

[ Post made via iPhone ]

Purely a guess, but I'm thinking the deflection is caused by one blade opening & catching a rib/bone while the other is still closed or not open to the same angle yet.

Yeah, I forgot to mention my last buck has a clear mark on a rib on entrance side. My arrows aren't lite but not super heavy either. 422 gr at 70lbs and 29.5" draw.

[ Post made via iPhone ]

I shoot heavier arrows at 60 pounds. Makes a big difference on deflections and pass throughs in my opinion man.

[johndeere506]

Its hard to really understand what going on with a moving target. Live animals that can move before and during impact make terrible repeatable experiments.

Kinetic energy is 1/2 m V^2

Momentum is just mv

By using lighter arrows, the momentum drops much faster that the KE does. I did calculations with a 300gr and a 400 gr arrow, and the lighter arrow retains [glow=red]93% of the KE[/glow], but only [glow=red]83% of the Momentum[/glow].

So, the guys preaching momentum, and the guys preaching arrow weight are saying the same thing. I agree with them as well.

The problem is, deer move. What if a high momentum setup is used, and after impact the deer jumps and the shoulder muscle starts changing the direction of that momentum by applying a force from a new direction on the arrow shaft. Or a rib deflection compounded by a deers initial movement? Lots of things cant be explained, but you just cant beat momentum. Math/Physics says so....LOL

edit...FYI i used a 70lb, 28inch, 330ibo for my example, with speeds of 293 for the 400 gr, and 326 for the 300grain.

[Bowhunting Brian]

My guess is the cutting diameter of the blades is so big. They can catch on more things and can get deflected. Try using a smaller cutting diameter head and see what happens.

[ Post made via Android ]

[Lockdown]

I have have had several deflections over the years, but none were major.

The buck I shot this year was probably the worst I've had yet. I thought he was broadside but could have easily been quartering to a little. The exit was 4 or 5" inches back from where I thought it should be, which I thought was not quite right. However it was lower than the entry by 3" or better. I shot him from the ground on level ground.

Between the two I know there was some deflection involved. I shoot 100 grain 3 blade fixed muzzies.

I've always got a pass through unless I hit the off shoulder, but this arrow didn't come out until 30 yards from impact. I'm sure a direction change on entry will effect penetration substantially.

Ridge runner in your case I can see how major deflection could happen by one blade fully contacting a rib, and the other sliding in between ribs. Now this is just speculation, but a two blade is way more prone to deflect than a 3 blade. I also feel this is true for a steep cutting angle on the blades. The kill zone head has 2 blades AND a steep cutting angle. If you do contact a rib like is described above, the blade that isn't contacting bone can freely cut rib meet an the shaft will freely kick off to the side.

Now if you imagine a fixed 3 blade, if one blade contact bone squarely, the other two aren't going to cut as freely as a lone horizontal blade. The 2 blades will start turning sideways and the back sides will start angling sideways and catching meat. That resistance will help get thru the bone.

I hope this makes sense.

[ Post made via iPhone ]

[JoeRE]

Its hard to really understand what going on with a moving target. Live animals that can move before and during impact make terrible repeatable experiments.

JD you are right, the physics of both a moving target & arrow, resistance of different tissues, damage to a broad head etc gets really complex. A person would have to measure the results of a huge number of actual shots before being able to "prove" much of anything. It would be really interesting to soup up a ballistics program to try to simulate all that though...

The underlying principles are still pretty simple. In layman's terms the definition of momentum is the resistance to change in motion, meaning what it takes to stop that object from moving (or change its direction). That sounds like penetration to me.

If I were God for a day I would delete every mention of kinetic energy from every bow hunter on the face of the planet and the world would be a better place

I don't mean to derail the thread. There are still a lot of factors that can cause deflections. They can be minimized with more momentum and changing nothing else or solved by diagnosing and fixing the exact reason behind the deflection (such as ferrules bending, steep cutting angle blades, or forward opening blades kicking off ribs).