Summit Treestands
Difference in spine charts?
Equipment
Contributors to this thread:
LINK 07-Feb-22
LINK 07-Feb-22
sticksender 07-Feb-22
LINK 07-Feb-22
timex 07-Feb-22
LINK 07-Feb-22
x-man 07-Feb-22
timex 07-Feb-22
Beendare 07-Feb-22
WV Mountaineer 08-Feb-22
timex 08-Feb-22
goyt 08-Feb-22
DanaC 08-Feb-22
WV Mountaineer 08-Feb-22
ELKMAN 08-Feb-22
Inshart 08-Feb-22
DanaC 10-Feb-22
Whatthefoc 11-Feb-22
x-man 11-Feb-22
Whatthefoc 12-Feb-22
wildwilderness 12-Feb-22
Buck Watcher 12-Feb-22
x-man 12-Feb-22
timex 12-Feb-22
wildwilderness 12-Feb-22
Whatthefoc 13-Feb-22
ELKMAN 13-Feb-22
Whatthefoc 13-Feb-22
x-man 13-Feb-22
Mpdh 13-Feb-22
timex 13-Feb-22
Whatthefoc 14-Feb-22
x-man 14-Feb-22
timex 14-Feb-22
x-man 14-Feb-22
APauls 14-Feb-22
timex 14-Feb-22
x-man 14-Feb-22
x-man 14-Feb-22
timex 14-Feb-22
x-man 14-Feb-22
Scooby-doo 14-Feb-22
2Wild Bill 14-Feb-22
timex 14-Feb-22
carcus 15-Feb-22
x-man 15-Feb-22
timex 15-Feb-22
x-man 15-Feb-22
x-man 15-Feb-22
timex 15-Feb-22
x-man 15-Feb-22
Whatthefoc 15-Feb-22
x-man 15-Feb-22
Grey Ghost 15-Feb-22
sticksender 15-Feb-22
brunse 04-Apr-22
Shawn 06-Apr-22
wyobullshooter 06-Apr-22
x-man 07-Apr-22
From: LINK
07-Feb-22
Why do some spine charts like Carbon express say a 350 spine arrow is fine for an 80# bow at 28” arrow while others like gold tip recommend a 300 and is on the verge of a 250 spine? Is spine not measured the same regardless of the manufacturer?

From: LINK
07-Feb-22

LINK's embedded Photo
LINK's embedded Photo
LINK's embedded Photo
LINK's embedded Photo

From: sticksender
07-Feb-22
Shaft deflection (or "spine") is tested under one standard, but recommending a deflection minimum for a given bow weight and shaft length is somewhat subjective.

From: LINK
07-Feb-22
One chart having it well in the 350 camp by several inches and pounds compared to the other nearly suggesting a 250 seams really subjective.

From: timex
07-Feb-22
I could be wrong but in my 40+ years of both trad & compound shooting iv always done better with an arrow on the weaker side & its been my experience that the majority of folks with tuning problems are trying to make too stiff a shaft work & especially with trad bows.

From: LINK
07-Feb-22
Timex do you believe that to be the same with compounds? I’ve always heard to error on the side of stiff.

From: x-man
07-Feb-22
Actually you can't group Trad and modern compound together. Trad bows need borderline weak to produce the correct amount of archers paradox.

Modern compound bows shot with a release and proper form almost cannot be too stiff.

From: timex
07-Feb-22
I guess I'm just old school but I tune a compound the same as a trad bow well sort of. I have a short draw 26 with trad & fingers 27 with release & compound. With trad bows I start with a full length shaft purposely week & slowly shorten it until good bare shaft flight is achieved. With a compound I set my rest center the bow string with a Lazer rest alignment tool & then go through the same arrow shortening process until good bare shaft flight is achieved. Again I'm no expert but I believe tuning the arrow to the bow is better than selecting a shaft & then adjusting the bow rest to make the arrow work. Or adjusting the bow to the arrow. Hope this helps.

From: Beendare
07-Feb-22
Whoah, my experience has been the opposite of Timex.

sure exact spine matters in a trad bow as you need the archers paradox.

Not so with a compound....I and many of my experienced friends have been shooting an overspined arrow through a center shot compound for years and it tunes perfect. No reason it wouldn't.

IN FACT, Almost all of the tuning problems I've seen are due to guys being underspined with BH's.

08-Feb-22
You can’t get too stiff an error on a modern compound. And, it’s my experience that trad guys shoot too weak of an arrow. YMMV.

From: timex
08-Feb-22
Here's a perfect example of my experiences & again perhaps im wrong but it's what I was taught & have always done. I Shoot a bowtec 101st airborne @ 70# trophy taker drop away & release with the same arrow & glue in glue on adapters & 130 grain zwicky delta heads & 125 field points for 10 years. Decided to drop the bow down to 60#s and field points still flew straight & hit where aimed but broadheads were now hitting left of field points. So now slightly STIFF... I did away with the glue in glue on adapters & went with an insert & short screw in broadhead adaptor bringing my broadhead weight to 155 & switched to 150 field points. thus slightly weakening the shafts & wala broadheads came back to same impact point as field points never touched rest or made horizontal sight adjustments. Did have to change vertical pin gaps... Now perhaps the expandable crowd can shoot whatever ya want But put a big fixed 2 edge on the end and not so much. In fact I know not !!!

From: goyt
08-Feb-22
Some of the charts have to be adjusted based on factors such as bow speed. I am not sure about the charts you are using. Plus, in the first chart it looks like a 300 spine is recommended for some shafts. Not all 300 shafts have exactly a .300 spine so the charts will differ a little. Finally, a heavier shaft will accelerate slower are requires less spine.

From: DanaC
08-Feb-22
"it’s my experience that trad guys shoot too weak of an arrow. YMMV."

It's been my experience that most traditional shooters are more likely to short draw, making the shaft effectively stiffer. So they're better served by a slightly lower spine, *unless* they have really good, consistent draw length and a clean release.

08-Feb-22
We might be talking along the same line Dana. I am in 100% agreement with you. Snap shooting has been adopted by the “instinctive” shooter crowd. It’s effective too. At karate range. But, it also lends to short drawing. Which leads to an over spined shaft; outside of carbon on a center shot trad bow.

From: ELKMAN
08-Feb-22
My tuning/shooting experience over the years has definitely fallen on the timex side of this debate. I can't explain why, but when I go on the weaker side of the spine and get that exact tune the set ups just seem SOOOO much more forgiving and easy to shoot. No clue why. And I do A LOT of tuning... Go figure.

From: Inshart
08-Feb-22
I've been setting up and tuning my own bows since the late 70's. For me, a stiffer spine has always tuned better then an under spined arrow, especially if you are going to shoot a heavy broad head.

From: DanaC
10-Feb-22
"especially if you are going to shoot a heavy broad head. "

A heavier head effectively make the shaft shoot weaker. So...

From: Whatthefoc
11-Feb-22
I have a set of field points that go from 100 to 300 grains, in 25 grain increments. I can go from a tail left tear to a tail right tear by changing nothing but the tip weight. In the middle somewhere, there is a weight that delivers a perfect bareshaft bullet hole thru paper. That would suggest to me that it is possible to be underspined or overspined with a modern compound.

As Crowder would say ‘change my mind’.

From: x-man
11-Feb-22
Whatthefoc, that falls in line with the same reasoning as a broken clock being right twice a day.

And I can shoot perfect bullet holes thru paper with my 45# target bow shooting a150 spined target arrow.

See what can be done with a proper tune?

From: Whatthefoc
12-Feb-22
X-man … achieving proper flight is a multi-varied equation. There are a dozen or more factors that all contribute to how that arrow flies.if your point is that one of those factors can hide another, I would agree.

I was sharing my opinion that we can in fact have ‘too stiff’ of an arrow with a compound - contrary to an earlier post on the thread.

I love a good metaphor, but your snarky broken clock reference makes you sound a little cuckoo.

12-Feb-22
You must be sure that you are reading actual spine and not arrow shaft “model number”.

I thought carbon express did that which was stupid- having a different model name than the spine of the arrow?

From: Buck Watcher
12-Feb-22
CX size number is not the spine.

CX Sizes/Spine: 150 (.500" spine), 250 (.400" spine), 350 (.340" spine)

From: x-man
12-Feb-22
And I was merely pointing out that your example is wrong. Your centershot is initially incorrect. Your example reads more in line with how a trad setup reacts with point weight tuning. An important step when you have archers paradox involved.

A modern compound with a release and a stiff enough arrow will not flex the shaft on release. Allowing one to change point weight without changing arrow flight characteristics.....when your arrow moves from tail left to tail right simply by changing point weight, that tells a good archery technician that the bow is not tuned yet. Or, you have a lot of hand torque.

From: timex
12-Feb-22
X-man I'll have to disagree. Perhaps with expandable broadheads your theory holds true. But put a big fixed 2 edge head on just any stiff enough shaft & the chances of field points & the broadheads having the same impact point is highly unlikely ...

12-Feb-22
Thanks Buck Watcher-

I could never understand why Carbon Express would do that

From: Whatthefoc
13-Feb-22

Whatthefoc's embedded Photo
Whatthefoc's embedded Photo

From: ELKMAN
13-Feb-22
Whats the question

From: Whatthefoc
13-Feb-22
The question is for xman - we are headed toward an ‘agree to disagree’ moment.

“ A modern compound with a release and a stiff enough arrow will not flex the shaft on release. Allowing one to change point weight without changing arrow flight characteristics..”.

WTF?

From: x-man
13-Feb-22
"X-man I'll have to disagree. Perhaps with expandable broadheads your theory holds true. But put a big fixed 2 edge head on just any stiff enough shaft & the chances of field points & the broadheads having the same impact point is highly unlikely ..."

Says everyone who doesn't have a tuned bow. There are hundreds of guys here on this very forum who can tune their bow so that they can hit same point of impact with field points and fixed head BH's.

whatthefoc, you are using a 40 year old paper tuning chart... please get with the new century. I for one would be glad to teach you how a modern compound bow actually functions. just ask

From: Mpdh
13-Feb-22
I think it’s physically impossible for an arrow to not bend when it is hit with 60 or 70 lbs of force on one end. It may not be much, especially if the shaft is over spined for the setup, but it still bends.

From: timex
13-Feb-22
X-man...go to the top of this thread & read my 2nd post.

A bow I had shot for 6 years I decided to turn down from 70 to 60# field points hit the same but fixed 2 edge now hit left indicating slightly stiff. I changed my broadhead adaptors bringing my broadhead & field point weight up 25 grains & now both are back to the same impact point. Never changed anything on bow except sight pin gaps.

Before you go on any further with your (any stiff enough not to flex shaft) nonsense I'd suggest you watch a slow mo video of an arrow leaving a compound bow.

From: Whatthefoc
14-Feb-22
One more x for xman

From: x-man
14-Feb-22
You guys have been watching too many youtube videos. Paper doesn't lie. perfectly round bullet holes at the end of the bow and every distance from there out to the targets in my indoor tuning range tells me(and every other reputable archery tuner) that a properly tuned modern compound bow with a stiff enough arrow shaft will not bend the shaft at release. After all, crossbow bolts don't flex, and they have 175# of force behind them....

Yes, there are still a large number of old-school guys who still read the Easton Tuning Guide which was written in the 1970's. Back when archers paradox was a real thing (it still is if you shoot fingers or trad). And YES absolutely if you watch an Olympic archer shoot in slow motion, those arrows flex like crazy. Fortunately they don't have to shoot with a large fixed broadhead steering the arrow out front. Every time your hunting arrow flexes, that broadhead will steer your arrow off-line. That's physics at work. Ever bend the tip of a paper airplane? Bowhunters with weak spined arrows will rarely group field points and broadheads together because that flexing arrow shaft catches air at the front blades and it goes in that direction. If you have enough spin on your arrow it will corkscrew around it's intended path and head in the right direction but,... your broadhead arrows may hit high at 20 yards and left at 30 yards ect... by comparison to your field points.

It's obvious you're in over your heads. There's no shame in admitting that and taking this opportunity to learn how to properly tune your bow. You don't have to learn from me if your pride won't allow it. Search "The Nuts and Bolts of Archery" it's written in this century at least.

From: timex
14-Feb-22
Well we're just gonna have to agree to disagree.

My bowtec 101st airborne with drop away rest set to center with Lazer shooting 70# & 27" radial x weave 200s can't remember the spine. 340 I think. And 125 heads Would group zwickey delta heads & field points together to 80 yards & I busted many a nock at 50 yards & even a few Robin hoods at 50. Then I dropped the pounds down to 60 making my arrows stiffer & broadheads hit left.

Increased point weight & broadheads came back to same impact as field points.

This completely debunks your stiff enough will shoot anything therie. In fact I'd be willing to bet 100 against 10 that you've never even shot a 1&3/8 or wider fixed 2 edge heads. In fact pm me your address & I'll sent ya a 1.5 wide magnus classic so you can watch it do some boomerang type stuff at about 40 yards with your any stiff arrow will work setup.

From: x-man
14-Feb-22
My shop was a Magnus dealer and my son was a staff shooter for Woody Sanford at Magnus. I know them very well. Please call Magnus and ask to talk to Mike Sohm. He will back my story.

From: APauls
14-Feb-22
Couple years ago I could get my fixed heads to tune to my FP. Was constantly chasing withy adjustments and couldn't catch up. I had found some cheaper arrows that were a little too stiff and all the "can't be too stiff" talk was still in my memory.

Went to the archery shop, he gave me a couple correctly spined arrows and I was good to go. Not sure if that is because I was using a biscuit? I 100% believe guys get great tune with arrows that are way too stiff, but it wasn't my experience.

I wonder if you can get great tune with an arrow that is so stiff it doesn't bend at the shot like X-man states, as well as the "right stiffness" but maybe there is a problem range with in between being a little too stiff yet bending at the shot? I dunno. I rarely change my setups so once I've got the solution I am good for years. I don't muck around with it as much as many guys.

From: timex
14-Feb-22
I fully understand what he's saying take a 50# target bow 200 spine shafts with 75 grain nibb points & their so stiff their probably gonna go straight. I know how to tune a bow been shooting both trad & compound for over 40 years the majority with fingers. Wasn't until I bought the bowtec that I used a release.

I'm not what I'd consider a great bow shot but have shot mid 290s indoors in bowhunter class. Fingers pins & short stabilizer with a 80# hunting bow & I've also killed 14 deer in a season with a bow & big fixed 2 edge heads. So I'm not some stooge that is just spewing off on the keyboard.

Perhaps I comes down to the individual & probably bow torque or lack of it being the determining factor all I know is I've always tuned better on the week side. Fingers or release.

From: x-man
14-Feb-22
There isn't a large percentage of archers willing to fine tune their equipment. Which is why you hear a lot of statements like "you can't hit same POI with large fixed heads" " my bow won't shoot fixed heads with my practice points so I sight in with my broadheads" " my bow won't shoot fixed heads with my practice points so I use mechanical BH's"

I'm not saying everyone [should] use an ultra stiff arrow. But,... I do know that every bow I have ever sold and tuned will shoot a stiffer shaft than the shaft tuned with without changing anything but the sight elevations to compensate for any added or reduced weight.

Another observation is that almost every bow shooter who starts out shooting fingers will almost always torque the grip. That's a hard habit to break. And shooting a weak shaft can "mask" some torque issues. That doesn't mean however that it's properly tuned. It just means that you've found by trial and error the shaft flex that matches your hand torque. A different shooter could grab your bow and not hit the same point of impact that you do. Which is a tell tale sign. While,...a properly fine tuned bow should be sighted in for any shooter of the same draw length with good form.

From: x-man
14-Feb-22
Apauls,

You likely improved by going from "cheap" arrows to arrows with a more consistent spine. Think about it, do you really want an arrow shaft that flexes as it goes through a WB hole? If a shaft flexes more than the diameter of the hole, it's going to get hung up in those bristles.

From: timex
14-Feb-22
So your an expert bow tuner but can't get the same weight field points & fixed heads to hit the same spot.

I'm done with this conversation.

From: x-man
14-Feb-22
Yes I can. Your reading comprehension skills need improvement.

From: Scooby-doo
14-Feb-22
Timex is correct. Deflection is deflections for carbons the weigfht is applied at 14" centers and supported on each end 28"s apart. Manufacturers alway err on the stiff side I believe due to liability issues. I shot 67#s for a lot years with a 27" arrow and a 27.5" draw. I shot .400 spine with 175 to 190 grains of point weight. 90 percent of guys would say no way that shaft is too weak. It tuned perfectly. Shooting 54#s and 240 grains of point weight now with same arrow is no issue. The thing is with todays rests and the new technology in arrows, as long as you are not way off, you can get most arrows to tune.

From: 2Wild Bill
14-Feb-22
Silly me, thought this thread was about politicians.

From: timex
14-Feb-22
Scooby-Doo... good to hear from ya. I still have that timberhawk.

I also have to question the finger shooters torqueing the bow statement ??? Myself personally hold or actually don't hold a compound the same irregardless of whether there's a tab or release in my other hand.

Now had he said trad bow shooters & especially asl shooters that switch to compound tend to hold & torque the bow I'd parcallaly agree with that.

From: carcus
15-Feb-22
My experience in the last year, I got bullet holes with easton axis 400, 340 and 300s out of my 70 pound bowtech solution, 70lb pse xpedite , 65 pound pse nxt 31 and 60 pound pse evl 34. All bows shot all arrows the same! lol Those axis are great arrows, especially match grade

From: x-man
15-Feb-22
"Now had he said trad bow shooters & especially asl shooters that switch to compound tend to hold & torque the bow I'd parcallaly agree with that"

That is exactly what I said....

From: timex
15-Feb-22
Perhaps your comprehension needs some help as well.

You said = almost every shooter who starts out shooting fingers will almost always torque the grip.

Plenty of folks out there that started out shooting compounds with fingers.

And in fact still do. I'm currently shooting an Oneida Phoenix with fingers.

From: x-man
15-Feb-22
Fingers is fingers, doesn't matter what's on the end of the limbs.

From: x-man
15-Feb-22
"And in fact still do. I'm currently shooting an Oneida Phoenix with fingers."

and yet you're trying to give advice relevant to shooting a modern compound with a release...that speaks volumes.

From: timex
15-Feb-22
Dude your a trip...

"Fingers is fingers doesn't matter what's on the end of the limbs"

So the fact that with one type of bow your holding the full weight of the bow at anchor. Back, Shoulders, arms, hands compressed by the full weight.

And the other bow type has 70 - 80% letoff back, shoulders,, arms,, hands relaxed by the letoff has nothing to do with it. ""(((REALLY)))""

The more you post the more I think you are full of poop

From: x-man
15-Feb-22
The statement about fingers was in regard to hand torque on the bow.

Reading comprehension please... you keep digging yourself in deeper and deeper.

From: Whatthefoc
15-Feb-22
X-man … I had no idea you ran an archery shop. Where is it? I need to drop in and buy a bow. Maybe some overspined arrows as well. Soak up the intelligence.

From: x-man
15-Feb-22
You're welcome any time. I'm retired from retail now that we're empty nesters but the shop is still here.

There are dozens of former customers on this forum.

From: Grey Ghost
15-Feb-22
I have to agree with x-man on this one. It all boils down to nock travel. Assuming you have 2 cams of equal size that are timed perfectly, and the arrow is shot from the true center of the string, with the rest at the vertical center of the bow, you really can't over-spine the arrows.

Matt

From: sticksender
15-Feb-22
FWIW, changing a bow's draw weight means moving the limb bolt(s), which can subtly change bow geometry such as cam lean at brace and full draw, and therefore change center shot. Moving limb bolts can also effect draw stop timing and nock height. I'd want to check those things first, before assuming a point of impact change was related to spine.

From: brunse
04-Apr-22
I follow x-man’s advice often. Very Very knowledgeable for those new to bowsite.

From: Shawn
06-Apr-22
All arrow charts err on the side of stiff, it is a liability thing. I have owned spine testers a long time and folks have no clue how much the dynamic spine stiffens when cut down just a half inch. Most guys today shooting with a 28" draw shoot a 26.5 or 27" arrow. I can assure you that as long as you stay around or under 70#s a .400 spine will be fine with heads from 100-175 grains ecsp. when cut to 26.5"s. When you get to 28" shafts and longer and draw weights up over 70#s and point weights getting heavier than 340's or stiffer will do folks well. I believe as Timex said, a lot of folks shoot too stiff of a spine!! Folks say its hard to do that today but it is one reason guys cannot get fixed blades to fly. A perfect tune is a tad weak with a field point is perfect than add a broadhead and it stiffens the dynamic spine a tad and you are good to go. Shawn

06-Apr-22
Shawn, I can blow your theory completely out the window, and know several others that can as well. I’m also curious how a tune can be a tad weak with a field point, yet by simply switching to a BH the spine somehow stiffens?

From: x-man
07-Apr-22
I don't think anyone takes Shawn serious on here. I wouldn't waste your time trying to change his mind...

  • Sitka Gear