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arrow spine?

My buddy and I were shooting yesterday and we happen to get a video of a .340 spine arrow robin hooding an old arrow haft shaft we had in the target to hold a orange sticker in place. When it hit you can see the arrow ripple and bend like no joke. Any further and it would have snapped. The arrow seems fine after close inspection but I am curious if you think any damage occurred to the structure of the arrow? Would you continue to shoot it?

I have shot more robin hoods than I can remember. Both carbon and aluminum. Just shot another two days ago. Not my favorite thing to do as arrows are expensive and is a waste. After showing them off for a few minutes, I always pull them apart and shoot the arrow again and again. Never had a problem. Hang the robin hood on the wall if you are worried and show it off as a trophy. I kept my first aluminum and a couple of my first carbon robin hoods. They make great conversation pieces, but as mentioned, now I pull them apart and move on.

your title is a bit misleading... but this link may be of help to your query.

Sandman,

Sorry about the title. There was supposed be a video that follows that shows the .340 spine arrow flexing a ton. I will get it posted soon I hope.

I know the safety procedures to check an arrow but my goodness I cant believe with as much flex as we saw that the arrow would be completely undamaged even though it appears to be fine. The arrow almost bent in half. A still shot of it shows it made a steep V shape. I would also think the arrow straightness would now be affected and I would think the arrows spine would be undermined.

Will try to post the vid tonight and you wont believe how much it bent. I still cannot believe it did not break. Maybe I can load the still pic and get the vid up later.

This is a pic of the video where I stopped it and snapped a pic with my phone. Not the greatest quality but it shows what it did.

Is it possible for it to do that and be completely undamaged? It bent hard in 2 spots actually. It's hard to see the 2nd bend but it bent badly where it went into the other arrow shaft too.

It looks undamaged but wow...I didn't think an arrow could take that.

Amazing pic. Does that arrow have any wobble to it if you spin it?

No wobble that I see.

Here is the video. My arrow 1st with normal flex and then my massive flexing and bending arrow to the nth degree and then my pal shot his with fairly normal flex. lol......I don't think most archers realize how much arrows really flex when they don't hit exactly flush or straight in. Some flex is normal but my arrow almost snaps and that is incredible that any arrow can withstand that much force and come out looking undamaged.

Optical illusion? Like the old rubber pencil trick.

im seeing it but im not believing it. that is an awesome video. im sure there is an explanation on why it looks that way. i suspect its some form of optical distortion. look how long your vanes look on the "bent" arrow as compared to the stationary ones. either that or the fact that it is recording so much data with that crazy high frame rate its showing the front before the back, just not at the same time. Man, i dont know. cool video though.

Not an optical delusion but I am sure there is a tiny amount of stretch due to the speed. Kinda like a blur so it may be 10% more than it actually was but that arrow did flex very, very badly. In normal speed you do not see the fletching's elongate like that. This is in super slow-mo speed. If it would have flexed anymore it would have broken in half IMO. My buddy has video of a few arrows that have flexed less and snapped.

Note worthy. Anytime an arrow nicks another and throws it off its straight line motion we see more arrow flex. It is hard to see it but the last shot on the vid you will see my arrow fletching's move just a bit before the loosed in flight arrow hits the target. This is why the last arrow flex's pretty good IMO. My 1st arrow did the same but not near as badly because it did not change direction as much. I will no longer shoot groups like this anymore. I will move around the target instead. I am at times shooting so tight that my arrows are stacking and I am hitting them and causing the arrows to flex a lot where if they stay straight and don't change direction they normally flex only a little bit as the energy keeps pushing forward and straight in until it dissipates. I will try to get some vid up soon of what they do when they do not hit anything on the way in. Those last 2 where they hit something 1st and changed direction kicking some energy sideways instead of forward shows how much energy can be lost by an arrow that does not hit correctly..

The shot with massive flex clearly hit another arrow 1st and then started to move upward and came to a sudden stop when it Robin hooded that half shaft so it bent in 2 directions if you look at the tip. A lot of the energy went out the center of the arrow because it did not hit straight. A poorly tuned arrow that does not hit straight could do the same but of course no where near to that extreme.

I guess if you could get an arrow tuned where it had as little flex as possible on impact because it is flying straight and true then you would get the most energy possible forcing through the shaft and forward down the shaft where it belongs. I always try to get my arrows to tune where they always hit straight on with the arrow azz following straight behind the tip instead of it going all caddywampious on the way in. lol.... It will be interesting in coming weeks what we can uncover on the vids with poorly tuned arrows that don't hit straight on versus arrows that do hit directly straight front to back.

This is why I don't shoot groups with my compound anymore. Arrows are too expensive to wantonly destroy.

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