Here i go again...Carbons (Update #2) a blow by blow of trying to tune a carbon

[LongStick64]

Look into the CX Maxima Blue Streak carbons, remind me of the Grizzlystik arrows by Alaskan Bohunting supply, but with better components and they come in longer lengths than the Beman. These shafts are Spine Weight Forward.

[wtpops]

             

Well the footings did the trick. Put a 3" 2016 on the MFX 340 shaft and it stiffened it up just right. The first bare shaft out of the Boarder Black Douglas flew so good i got that 10 year old, i just got what i always wanted smile on my face, I must have shot the bare shaft 15 times and it hit right where i was looking and some of the best flight I’ve seen out of my shooting in a long time. I am so happy i could just....well you know.

Footed and fletched up a cupule and all i can see is a white knock with fletching spinning around it as it flies right to where I’m looking.

Here are the specs on the finished arrow...
32" MFX 340
75 grain HIT insert
175-grain point
32 grain 3" 2016 footing
3-grain point adapter ring

Total up front 285 grains
Total arrow weight 662 grains
Comes to 11 gpp
20% FOC

This thing it going to be tipped with a 175 grain VPA Terminator.

This is going to be one hog-killing arrow.

Did i say          

[scedvm]

Excellent news!  Thanks for keeping up with the thread and glad you found what you were looking for.

[wtpops]

Just a tip for all you long draw guys:

I used the footing as a tunning aid and not so mush as a protection aid, something i never thought of doing before. The footing will make this arrow almost indestructible and ofcourse is a huge plus even though that was not my main objective.

These arrows did end up a bit heaver than i like but they are flying so good out of my Boarder with the HEX 4 limbs that i am very pleased with this arrow. The Boarder is about 3# heaver than my Widow that i was trying to tune these to and the HEX 4 limbs seem to have a little more kick so at 11 gpp I dont seem to have any drop in trajectory (the trajectory that im used to). I think its going to work out well.

[atatarpm]

Glad to hear this thread!  From another 31 incher

[JDunlap]

How far away were you shooting your bareshafts?

[cacciatore]

For hogs that would be a killer arrow.

[Shawn Leonard]

Anything added to the end of the shaft will weaken it, did you add it to the nock end?? Also if added to point end it will become a breaking point as anything much past the insert creates a point at which the shaft will break. Shoot a fletched shaft thru paper at 12 ft. or so and see what type of tear you get! Shawn

[Shawn Leonard]

I re-read your post and do not see how even adding 3"s to the insert end can stiffen the dynamic spin. The last bit of a shaft does not go thru paradox that I am aware of, please explain how it acts to stiffen the shaft. Shawn

[DesertDude]

The lenght of the footing (3") may cause the shaft to act like is was cut shorter, Flex point would be behind the footing. If it was just weight added then it will weaken, I may have to cut different lenght footings and see what affect it has on static spine, if any..

[xtrema312]

I tried some longer footings and got more stiff acting flight, but not sure it was a stiffer arrow or just the dia. of the arrow moving it out from the riser.  You can also try larger or more silencers, thicker string, and a little something behind the strike plate to work it out.  I have been amazed at times what silencers changes will do.

It is not just you long draws that can have problems.  I draw 29 ½” and have issues with some bows because I fall between 500 and 400 spine.  I have the same too light and too heavy issues if my bows are lighter weight and or cut out from center.

[wtpops]

Originally posted by Shawn Leonard:
I re-read your post and do not see how even adding 3"s to the insert end can stiffen the dynamic spin. The last bit of a shaft does not go thru paradox that I am aware of, please explain how it acts to stiffen the shaft. Shawn

The HIT insert is 2" long when you add a footing that is longer than the insert, in my case 3", you are in effect making 3" of the arrow non-flexable and in my case turnning it into a 29" arrow.

With the 2" insert and no footing it makes a 30" arrow. The 32grains added to the tip is no way near enough to off set the 1" loss in carbon arrow length therefore making it stiffer.

[wtpops]

Originally posted by Shawn Leonard:
Anything added to the end of the shaft will weaken it, did you add it to the nock end?? Also if added to point end it will become a breaking point as anything much past the insert creates a point at which the shaft will break. Shoot a fletched shaft thru paper at 12 ft. or so and see what type of tear you get! Shawn

In reguards to the breaking point you are correct but all i really did is move my breaking point from 2", the back of the insert, to 3" the back of the footing.

[wtpops]

Originally posted by JDunlap:
How far away were you shooting your bareshafts?

From 15 then 20 yards, thats all i can get out of my back yard.

[Shawn Leonard]

Sorry but watched a bunch of slow-mo footage and the last few inches does not flex upon release or appear to flex, it does on impact but not wrapping around a riser on trad bow or at the shot, the flexes is several inches behind the point at the least more than 3 from what I have seen. Shawn

[wtpops]

Originally posted by Shawn Leonard:
Sorry but watched a bunch of slow-mo footage and the last few inches does not flex upon release or appear to flex, it does on impact but not wrapping around a riser on trad bow or at the shot, the flexes is several inches behind the point at the least more than 3 from what I have seen. Shawn

I have seen a few of those videos my self and agree with you on what you see. But we all know and i assume agree that to tune a week arrow you cut some off and it stiffins the arrow all i did is in effect shorten the arrow with out cutting it off by makeing it non-flexable.

Also with Stu's calculator, when he first came out with it I asked him if he had accounted for the insert making that first 1" of the arrow non-flexable he said he had not and soon changed it to account for it. Also in the instructions it states that if you use a longer insert such as a HIT or the longer 100 grain brass insert to account for it in the calculator.

All i have done is used this principal and made the first 3" of my arrow non-flexable which has the same effect as cutting off 3" as far as dynamic spine goes.

[Shawn Leonard]

There you go than, I do not believe in Stus calculator. Escp. when it come to FOC. I have tried it and entered all the correct info. and it is always wrong for me and my real world results. Shawn

[wtpops]

Originally posted by Shawn Leonard:
There you go than, I do not believe in Stus calculator. Escp. when it come to FOC. I have tried it and entered all the correct info. and it is always wrong for me and my real world results. Shawn

Ya the calculator does not work for me eather, to many form variables. But does work for most.

But the concept of a shorter shaft or one where a part of it is rendered non-flexable being stiffer is purity much a givin.

Anyway thank you for your input.

[katman]

Very glad to hear you got it worked out. That combo of weight and foc should penetrate well. Thanks for sharing your process, adds another tuning variable to the mix.

[Zbearclaw]

Hey pops congrats on finding "the" arrow!

That's all we really want anyway.  I got some .340 MFX Classics too and will hopefully get them dialed in here shortly.

regarding the flexing, the proof is in the pudding.  I have personally been baffled in the past as to why a shaft got stiffer when going from a longer insert but the same overall weight from a test arrow.  

The tip may not flex, but stiffening it does move the point that does flex farther from that tip, thereby making it stiffer like you found.  

When are you going pig hunting?