Stiff spine

[DanielB89]

I have some arrows that a buddy traded me.  They are all .340 spined arrows and came fletched.  I was wondering what would be the best way to tune the arrow that is already fletched?  

It is hitting about 5" to the left(Right handed) of where I am looking pretty consistently.  I was wondering If just raising the point weight some would move them back to the right some?

[JimB]

Raising the point weight will bring it in to tune but the question is,how much point weight?What is the .340's length and point weight now?What is your bow weight at your draw?

[McDave]

I like to have a bare shaft for every type of arrow I shoot.  If they were my arrows, I would trim the feathers back to the quill on one of them and then tune in the usual way. One advantage of leaving the quill and glue on when you bare shaft tune is that it makes the bare shaft closer in spine to the finished arrow, but still has the characteristics of a bare shaft.

[BigJim]

If you are shooting a bow pulling 55lbs and below, they don't make enough pt weight.

Pt weight is a very poor way to make arrows work unless you are already close. You should first ensure that they are the correct spine and then the correct length and adjust pt weight to suit.

good luck, bigjim

[JRY309]

I would strip one bare and find out for myself.Alot can depend on how long are arrows,how close to center is the riser cut and other factors.When I first started shooting carbon arrows,I bought some used ones that were already cut about a inch past my draw.They were showing alittle stiff,so I thought I could add more front end weight to weaken the spine.They got worse and were showing even stiffer with the more weight I added.They were bouncing off the riser insead of flexing around the riser.I did tune the same spine for that bow but started full length and tuned well and alittle over 1&3/4" longer then the used ones.

[mahantango]

.340 is a really stiff arrow. All you can do at this point is increase point weight - it could take a lot, and raise brace height.

[DanielB89]

I am shooting them out of a black widow MAIII THAT IS #53@28. I bare shafted a GT 5575 and could not get it to tune. I swapped to a beeman ICS .340 and had it bare shafting perfect. Then I traded my buddy and he had the .340 MFX's and they shoot a little different than the ICS BOW HUNTERS. I know the MFX's are skinnier, I just didn't know that that would affect it that much.
The arrows are not far out of tune, they just hit a few inches to the left.

[JimB]

Give it a try and see what happens.I couldn't predict how much it would take but be prepared to jump it up a bit.You can decide then if the overall weight etc is for you.I will say,I would also take the fletch off a couple,as others have said.The fletch will overcome some tune issues so they could be off a lot more than you think.Bareshafting would show that immediately.Good luck with them.

[DanielB89]

JimB, good point. I just assumed that since the other .340's bare shaft tuned well these .340's would also be tuned well. How would the MFX's being a skinnier shaft make them tune differently?

[MnFn]

It is startling how fast my 61-62# shoots 340's but I have not tried them in anything else.  They have the .75 grain hit insert  and 145 grain point but I don't really know how much weight has been added because the tip end has been re-enforced with a sleeve epoxied on.

Originally posted by DanielB89:
JimB, good point. I just assumed that since the other .340's bare shaft tuned well these .340's would also be tuned well. How would the MFX's being a skinnier shaft make them tune differently?

It may not have anything to do with the diameter of the shafts! One reason could be because neither are exactly .340 and the two different shafts are not the same as each other. I have never shot either of the two shafts you are playing with now.

I shoot 5575 Gold Tip XT Hunter (.003 straightness) black shafts. These shafts say they are .400 spine on the factory label. I run every shaft through a carbon arrow spine tester and group them into groups of .010 stiffness. I have probably run 25 dozen of these shafts through this spine tester AND NEVER ONCE HAD A SHAFT SPINE OUT AT .400. They are all stiffer and actually vary much more than I ever would have thought before doing this.

Bisch

[DanielB89]

Bisch,
I would have thought they would have been more precise than that.  I cut the feathers off one of the arrows and they flew very well.  On a few shots I did notice that it flew slightly weak.  And I do mean slightly. At 15 yards they were all flying well.

I did notice that the one arrow that showed stiff has a 150 grain head where the others had a 175 grain head.  Do you think that 25 grains would make that big of a difference?  If so, I could possibly bump up my head weight to around 200 or keep the same weighted head and use a brass insert.

[johnnyk71]

Originally posted by DanielB89:
I am shooting them out of a black widow MAIII THAT IS #53@28. I bare shafted a GT 5575 and could not get it to tune. I swapped to a beeman ICS .340 and had it bare shafting perfect. Then I traded my buddy and he had the .340 MFX's and they shoot a little different than the ICS BOW HUNTERS. I know the MFX's are skinnier, I just didn't know that that would affect it that much.
The arrows are not far out of tune, they just hit a few inches to the left.

I shoot .340 spined GT out of my RER Retro that is exactly the same weight as yours. 53#@ 28". They are 31" long. I use a 100-grain brass insert and 150 grain broadheads. they spine and shoot perfectly for me.

[JimB]

"Do you think that 25 grains would make that big of a difference?"

Yes,25 grs can definitely make a difference that could be seen with a bareshaft but probably wouldn't be noticed,shooting fletched,alone.

Originally posted by DanielB89:
Bisch,
I would have thought they would have been more precise than that.

You and me both. I started spining my shafts because I shoot a lot of 3D and a pretty high level compound shooter friend of mine told me that it would make a difference. It is just habit now. I don't know that it makes a whole lot of difference, but what it does do, is help with the "flyers". It gets my arrows all grouped together, spine wise, and I don't have one arrow way off at the end of the spectrum acting goofy compared to the rest of them.

Bisch

[DanielB89]

Originally posted by johnnyk71:
 

Originally posted by DanielB89:
I am shooting them out of a black widow MAIII THAT IS #53@28. I bare shafted a GT 5575 and could not get it to tune. I swapped to a beeman ICS .340 and had it bare shafting perfect. Then I traded my buddy and he had the .340 MFX's and they shoot a little different than the ICS BOW HUNTERS. I know the MFX's are skinnier, I just didn't know that that would affect it that much.
The arrows are not far out of tune, they just hit a few inches to the left.

I shoot .340 spined GT out of my RER Retro that is exactly the same weight as yours. 53#@ 28". They are 31" long. I use a 100-grain brass insert and 150 grain broadheads. they spine and shoot perfectly for me. [/b]

I think I will try out the brass inserts.  Unfortunately these arrows got to me already cut and they are 30.5 from back of point to the valley of nock(30" just carbon).

I do wish they were a couple inches longer, but I cant add what isn't there.  I received 28 shafts that were all new(but cut), so I hope to make these work.

[flyne]

The skinnier shaft will make a diffrence as the center of the shaft is closer to the center of the riser so basically it's like having a bow cut closer or past center cut  hope that makes sence
Jim

[Pivo]

I think the fact that they are relatively long is helping soften them up.  Lots of difference when you go adding a couple inches to an arrow IMO. If they were cut to 28.5" they would be aweful stiff for 53#

[johnnyk71]

Originally posted by DanielB89:
 

Originally posted by johnnyk71:
 

Originally posted by DanielB89:
I am shooting them out of a black widow MAIII THAT IS #53@28. I bare shafted a GT 5575 and could not get it to tune. I swapped to a beeman ICS .340 and had it bare shafting perfect. Then I traded my buddy and he had the .340 MFX's and they shoot a little different than the ICS BOW HUNTERS. I know the MFX's are skinnier, I just didn't know that that would affect it that much.
The arrows are not far out of tune, they just hit a few inches to the left.

I shoot .340 spined GT out of my RER Retro that is exactly the same weight as yours. 53#@ 28". They are 31" long. I use a 100-grain brass insert and 150 grain broadheads. they spine and shoot perfectly for me. [/b]

I think I will try out the brass inserts.  Unfortunately these arrows got to me already cut and they are 30.5 from back of point to the valley of nock(30" just carbon).

I do wish they were a couple inches longer, but I cant add what isn't there.  I received 28 shafts that were all new(but cut), so I hope to make these work. [/b]

hope it works for you. you should be pretty close. leaving them longer definitely helps. at hunting distances, a heavy front end shouldn't hurt your flight, and should pack a pretty good punch. i long ago went to using the same weight arrows for hunting as 3-D or everything else. less adjustment that way. remember, you can even go a tad heavier up front if they aren't spinning quite right.

[DanielB89]

Well if anyone wants to trade some full length ones for these, i will gladly do so!     It is just came with the trade!