Spine Uncertainty

[Jahvette20]

I’m running low on arrows and debating a new build. Currently I shoot a 27” (Carbon2carbon) axis 5mm mg 340 with 175gn up front, a 4” wrap, and 3 blazers out of a RX1(80% mods) at 71# and 26” draw. These tune well but I’m considering a 4 fletch with aae max stealth. Do I stick with the 340s and keep them at 27” or go to a 400 and cut them to 25”? I figure the new vanes will add approximately 12 gn in the back. Any feedback is appreciated. Thanks

 

[cobbc03]

I would not go up in spine. Either stay at 340, or go down to 300, it seems to me you may be slightly under spined as is.

 

[Zac]

I have found that you may have to put a half twist in a yoke when going from three Stealth's to four. Definitely not a spine change for a single vane difference.

 

[Billy Goat]

Are you looking for anything particular? If chasing a lighter arrow you could probably do the 400 spine, it might end up shorter than 25" but with a 26" draw you should have the room. When running that much weight up front I can't imagine your chasing a lighter arrow. Your going to loose some durability going to a 400 from a 340. I wouldn't change it unless you felt like there was a really good reason to.

Might be your going to have trouble finding those arrows right now anyways, I do think some places have 400's. I believe 340's and 300's are hen's teeth right now.

 

[Wrench]

Glue one up and let it rip.....you will be able to see if it's something you can tune out with what you have going now.

 

[wayoh22]

Why would you cut your arrow 2in shorter? To make up for the weight from adding another vane + weight differential? Makes me think that if you have 2in to spare on an arrow that something is up.

Plugged your numbers into my calculator and you can be at a 340 or 300 spine. I'm currently running 4 fletch AAE Max Stealths with a 300 spine and love it. (29in Draw, 29.75in shaft, 67lb draw. Will be at 70lbs when I tune it.)

 

[Jahvette20]

Thanks for the replies. I had a feeling I’m on the edge between 400/340 as is. I figured with adding the 12 gn in the back I could cut length which is always nice, possibly even drop 25 gn from the insert, both of which would make up for some of the extra drag another game will bring, and go weaker. The main reason for the 175 rather than 150 up front is it tunes better. I’ve never tried a 400 in this setup though and I don’t even have any to play with. And yes 400s are easier to come by right now.

 

[Billy Goat]

What is your system upfront to get to 175?

The longer your insert system is the shorter it's making your arrow. Depending on what insert you are running, you might already be loosing close to 2" of shaft length. Generally it's only an inch or so, however the hit inserts already take up more shaft space than standard inserts.

 

[Jahvette20]

What is your system upfront to get to 175?

The longer your insert system is the shorter it's making your arrow. Depending on what insert you are running, you might already be loosing close to 2" of shaft length. Generally it's only an inch or so, however the hit inserts already take up more shaft space than standard inserts.

Yes I’m running the full brass hit, 75 gn. Part of the reason I’m running long arrows.

 

[Billy Goat]

Yes I’m running the full brass hit, 75 gn. Part of the reason I’m running long arrows.

You were having trouble with a stiff spine?

Generally you can go a fair amount stiffer than what the charts recommend.

I can't remember how much that brass hit takes up off the top of my head, but I think it's atleast 1" more than what a standard insert would in a .246 shaft, so even tho your arrow is 27" CTC it's going to react more like a 26" arrow.

 

[Jahvette20]

You were having trouble with a stiff spine?

Generally you can go a fair amount stiffer than what the charts recommend.

I can't remember how much that brass hit takes up off the top of my head, but I think it's atleast 1" more than what a standard insert would in a .246 shaft, so even tho your arrow is 27" CTC it's going to react more like a 26" arrow.

Yes it’s about an inch longer. I wasn’t having trouble, they tuned well. I’m just thinking I’m borderline and if I add 12 gn in the back, drop 25 from the front, and shorten the arrow by 2” I could possibly go to a 400 which could have a few advantages as far as less drag/drop and more speed. Plus I probably don’t need all that weight up front but that what tunes well. Really I have no reason to switch other than playing around so I’m just reaching for opinions I guess

 

[N2TRKYS]

I like my arrows to be 1” in front of my rest. If I was borderline on spine, I’d go to the stiffer one. I definitely wouldn’t be adding extra weight to the rear of my arrows.

 

[Billy Goat]

Yes it’s about an inch longer. I wasn’t having trouble, they tuned well. I’m just thinking I’m borderline and if I add 12 gn in the back, drop 25 from the front, and shorten the arrow by 2” I could possibly go to a 400 which could have a few advantages as far as less drag/drop and more speed. Plus I probably don’t need all that weight up front but that what tunes well. Really I have no reason to switch other than playing around so I’m just reaching for opinions I guess

Drag will be the same, except for fletching, that will be a constant no matter the spine tho. You will increase speed by loosing arrow weight, that's a personal thing. I really don't like being below 280, some guys prefer a really heavy arrow no matter the speed. For the way I hunt I like speed when I can get it.

If your interested in playing with it go for it. You can't draw too many conclusions without experimenting for yourself. Might be you don't like the results and end up right back where you were. What is your intended target? With a shorter draw I don't know that I'd go too light for elk, deer it's not as big of a deal. I'm also not a fan of 4-fletch but that's just me. Lots of guys feel they get positive results from it. Experiment and find what works for you, I'd just recommend not experimenting with animals until you do feel really confident in your setup. I use to try to get away with the lightest spine possible, I don't anymore. Too much headache with tuning.

 

[N2TRKYS]

Order 3 Gold Tip Hunter XT 300(9.3gpi) arrows and 3 Black Eagle Carnivore 300(8.5gpi) to test out.

I did this a few months ago and found out both arrows fly pretty dang good. I like the Gold Tips, cause I’ve been using them in a different spine for over a decade. I liked the idea of the BE, cause you can increase foc easily(if that matters to you) without getting crazy heavy.

 

[Billy Goat]

Order 3 Gold Tip Hunter XT 300(9.3gpi) arrows and 3 Black Eagle Carnivore 300(8.5gpi) to test out.

I did this a few months ago and found out both arrows fly pretty dang good. I like the Gold Tips, cause I’ve been using them in a different spine for over a decade. I liked the idea of the BE, cause you can increase foc easily(if that matters to you) without getting crazy heavy.

Kinda curious what you would be testing there? Arrow brands? Same spine more or less, except for the variations within a spine size for a product line. At 27" your talking almost 19 grains difference. Not much once all the components are added.

The OP is asking about trying different spines, if anything he would be better served to order 4-400 spine and 4-300 spine to test against what he is currently using, see what tunes and how the speed/weight differences add up for what he is looking for out of an arrow.

 

[Jahvette20]

Drag will be the same, except for fletching, that will be a constant no matter the spine tho. You will increase speed by loosing arrow weight, that's a personal thing. I really don't like being below 280, some guys prefer a really heavy arrow no matter the speed. For the way I hunt I like speed when I can get it.

If your interested in playing with it go for it. You can't draw too many conclusions without experimenting for yourself. Might be you don't like the results and end up right back where you were. What is your intended target? With a shorter draw I don't know that I'd go too light for elk, deer it's not as big of a deal. I'm also not a fan of 4-fletch but that's just me. Lots of guys feel they get positive results from it. Experiment and find what works for you, I'd just recommend not experimenting with animals until you do feel really confident in your setup. I use to try to get away with the lightest spine possible, I don't anymore. Too much headache with tuning.

I took a bull last month with my current setup, at 25 yds full pass through. My primary target are whitetail here in PA however so speed doesn’t hurt that’s for sure. I’ve never messed with 4 fletch that’s why I’m thinking of tinkering with it but I definitely dont want to use 4 blazers which are what I’ve been shooting (3) for years. I’ve heard good things about the aae max vanes so I’d like to try them. I do like the heavy hit I’m getting with the current setup but the increase of speed may be worth sacrificing the say 60-70 gn I could potentially drop by going to a 400 cut shorter running 50 gn insert. I know I just need to play with each. Again, I just put this out there to suck up opinions and ideas. I do appreciate the feedback

 

[N2TRKYS]

Kinda curious what you would be testing there? Arrow brands? Same spine more or less, except for the variations within a spine size for a product line. At 27" your talking almost 19 grains difference. Not much once all the components are added.

The OP is asking about trying different spines, if anything he would be better served to order 4-400 spine and 4-300 spine to test against what he is currently using, see what tunes and how the speed/weight differences add up for what he is looking for out of an arrow.

Different weights, different foc, and different speeds/trajectory. There’s alot to be tinkered with with those two setups.

The charts I looked at suggested that he didn’t need to shoot 400s and 340 was iffy. Why not go stiffer, especially, if you’re loading the front?

 

[Marble]

It might tune well with the field points at 400 spine but I would be concerned about putting a broadhead on there and seeing what happens.

Thats my experience. The broadhead can amplify an issue or create one. However you want to look at it.

I was in the same situation sort of. A 340 shot well with 200 upfront with 4 fletch. A broadhead made it do wacky stuff. I switched to 300, same length, same tune. Put 175 up front and the arrows all flew together. Just my experience. Arrow weight went from 512 to 525 with the BAR.

Sent from my SM-G986U using Tapatalk

 

[Billy Goat]

Different weights, different foc, and different speeds/trajectory. There’s alot to be tinkered with with those two setups.

The charts I looked at suggested that he didn’t need to shoot 400s and 340 was iffy. Why not go stiffer, especially, if you’re loading the front?

My point is those two arrows it's not much difference. Inserts weigh the same, nocks weigh the same, I think they come from the same plant, just made to slightly different specs for the manufacturer but not certain. Epoxy is different between the two, I don't know that the carbon itself is any different. Both good arrows in my opinion, I'd use either assuming they fit into what I'm wanting to build. A Carnivore gets the nod for a slightly lighter arrow, or the GT ultra light. GT hunter is a good all around arrow.

If he cuts arrows back like he is saying it puts him in a way different realm on spine. Things start to change pretty quick with a shorter shaft. If he goes to a 25" or shorter arrow and looses a little tip weight he is going to be alright with a 400, I'd go ahead and stick with the 340 myself unless he is planning on only running a standard insert with a 100 grain head. I have run a 400 spine @ 27" from a 330 IBO bow @72# and 29" DL. Wasn't easy to tune, but it did work. I don't chase speed anymore like I did.

Cutting his shaft shorter is going to increase foc a lot. Ain't going to matter, but that will happen.

If wanting to try a different arrow weight but that is similar diameter to what he is using he can look at something like the BE rampage. Remember a rampage can use hits, so no need to use their half out system. Stick a standard hit aluminum insert (16g) in if wanting a light weight arrow. If wanting to play with heavier arrows go to a fmj. Gold tip kinetic would be a very similar arrow to what he is currently shooting, only .4 gpi heavier than what he is currently shooting if just looking to try a different arrow at similar specs.

Op has an arrow in excess of 450 grains. Not certain how heavy but right over 440 without vanes or a wrap, that's shaft, nock, and his claimed front weight. Hunting deer I wouldn't be concerned about being around 400 instead. Elk I'd stay right where he is. On my bows dropping from 450 gr to 400 gr is going to be around 13 fps, with his shorter draw he might not see as much of a difference. I'd prefer to have the 13 fps than the 450 grain for whitetail, for how I hunt. If he is hunting thick cover from a treestand and maximum shot distance is hardly 30 yards, he might be better to stay heavy. I hunt a lot of field edges and can shoot as far as I feel comfortable.

 

[N2TRKYS]

My point is those two arrows it's not much difference. Inserts weigh the same, nocks weigh the same, I think they come from the same plant, just made to slightly different specs for the manufacturer but not certain. Epoxy is different between the two, I don't know that the carbon itself is any different. Both good arrows in my opinion, I'd use either assuming they fit into what I'm wanting to build. A Carnivore gets the nod for a slightly lighter arrow, or the GT ultra light. GT hunter is a good all around arrow.

If he cuts arrows back like he is saying it puts him in a way different realm on spine. Things start to change pretty quick with a shorter shaft. If he goes to a 25" or shorter arrow and looses a little tip weight he is going to be alright with a 400, I'd go ahead and stick with the 340 myself unless he is planning on only running a standard insert with a 100 grain head. I have run a 400 spine @ 27" from a 330 IBO bow @72# and 29" DL. Wasn't easy to tune, but it did work. I don't chase speed anymore like I did.

Cutting his shaft shorter is going to increase foc a lot. Ain't going to matter, but that will happen.

If wanting to try a different arrow weight but that is similar diameter to what he is using he can look at something like the BE rampage. Remember a rampage can use hits, so no need to use their half out system. Stick a standard hit aluminum insert (16g) in if wanting a light weight arrow. If wanting to play with heavier arrows go to a fmj. Gold tip kinetic would be a very similar arrow to what he is currently shooting, only .4 gpi heavier than what he is currently shooting if just looking to try a different arrow at similar specs.

Op has an arrow in excess of 450 grains. Not certain how heavy but right over 440 without vanes or a wrap, that's shaft, nock, and his claimed front weight. Hunting deer I wouldn't be concerned about being around 400 instead. Elk I'd stay right where he is. On my bows dropping from 450 gr to 400 gr is going to be around 13 fps, with his shorter draw he might not see as much of a difference. I'd prefer to have the 13 fps than the 450 grain for whitetail, for how I hunt. If he is hunting thick cover from a treestand and maximum shot distance is hardly 30 yards, he might be better to stay heavy. I hunt a lot of field edges and can shoot as far as I feel comfortable.

I found that they were really different. There’s zero chance I’d shoot a 400 spine in his setup and see no advantage to it.

Definitely, should check the speed difference and not rely on rules of thumb to figure speed. Mine drops way more than yours. The trajectory was definitely different inside of 30 yards.

You just have to test it to find what you’re happy with, speed/weight wise.