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Discussion Starter · #1 ·
Pretty new archer so please cut me some slack. But I've been wondering about something. Is there a difference (or big difference) between say a 100 grain broad head with a 50 grain insert compared with a 150 grain broad head, for example (both in terms of how the arrow behaves in flight and how it behaves going in / through an animal)? Basically I'm wondering what the reasons are for different weight broad heads, different weight inserts, etc., and why you would choose to use one over another.
 

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Pretty new archer so please cut me some slack. But I've been wondering about something. Is there a difference (or big difference) between say a 100 grain broad head with a 50 grain insert compared with a 150 grain broad head, for example (both in terms of how the arrow behaves in flight and how it behaves going in / through an animal)? Basically I'm wondering what the reasons are for different weight broad heads, different weight inserts, etc., and why you would choose to use one over another.
Arrows are rated for static spine. 340 spine arrow means in the arrow stiffness testing machine,
the supports are 28-inches part, and the arrow stiffness testing machine uses a weight (880 grams)
and then, measures the thousandths of an inch, that the arrow bends.

340 spine means that the arrow bends 0.340 inches...340 thousandths.

So, the more broadhead weight you put on the front,
the heavier the insert you install at the front of the arrow....you make the arrow behave WEAKER when you fire the arrow.

So, when the draw weight is too high...70 lbs versus 80 lbs versus say 90 lb draw weight compound bow,
the MORE the draw weight, then, you need a STIFFER behaving arrow.

The longer the draw length, then, you need a STIFFER behaving arrow.

So, say you shoot a 50 lb draw weight compound bow, and the broadheads and field points all group together at 30 yards, when you shoot a 400 spine arrow, and a 150 grain broadhead with the 50 grain brass insert. That means you have a total weight of 200 grains up front (broadhead and insert).

So, then you decide to shoot a 60 lb draw weight bow, a really FAST compound bow with say 350 fps for the IBO speed rating. So, you bump up to the 340 spine arrow, and you need to drop down to the 125 grain broadhead and the 12 grain aluminum inserts...so, you now have only 137 grains up front.

So, then, you decide to shoot a 70 lb draw weight bow, and an even FASTER compound bow with say 360 fps for the IBO speed rating. So, you bump up to the 300 spine arrow, and drop down to 100 grain broadheads and the 12 grain aluminum inserts....so now you have only 112 grains up front.

MORE speed, MORE draw weight, means you need a STIFFER arrow, and LESS weight for the broadhead, and LESS weight for the insert...to make the arrow behave STIFFER.
 

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Pretty new archer so please cut me some slack. But I've been wondering about something. Is there a difference (or big difference) between say a 100 grain broad head with a 50 grain insert compared with a 150 grain broad head, for example (both in terms of how the arrow behaves in flight and how it behaves going in / through an animal)? Basically I'm wondering what the reasons are for different weight broad heads, different weight inserts, etc., and why you would choose to use one over another.
So, 100 grain broadhead or the 150 grain broadhead or the 200 grain broadhead.
So what?

12 grain aluminum inserts, or 50 grain brass inserts or 100 grain brass inserts.
So what?

MORE weight up front, means MORE foc (Front of Center balance).
MORE weight up front, means MORE total weight for the entire arrow.

Who cares? More total weight. Big deal, right?
MORE weight means MORE momentum. Momentum is the resistance to change direction, and resists change in speed.

THINK a freight train. A heavy freight train, moves slower but will blow through brick building after brick building, and not lose very much speed. Think economy car plowing into a tree, trying to BLOW through a tree. TREE always wins, and the economy car (less weight than a freight train) is crushed like a fly.
 

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Concerning mostly compounds and hunters and that evolution as I sort of saw it around here. Traditional equipment staying more true to the original form.

Long ago before the internet, and cell phones, and even before people had more than one tv set in the house.
Mostly archery was slower arrows with a more traditional longer broadhead, people where pretty satisfied shooting with something that looked somewhat like medieval armament. And honestly for those speeds and arrows it did work good. Typically a longer broadhead when made with some thought to durability its going to weigh something. If you look at the Zwickey broadheads they were popular, look at their weights. And old Chuck Adams was traveling about kicking the legs out from under about anything that walked with one of them.

Then....things started to speed up, faster arrows. Shot flatter,had a lot of peoples attention, cause many did not have or use any kind of range finder, and a misjudged yardage would have your arrow stick in the ground right under the belly of some animal and would make you're heart sink. And ....people were still shooting with fingers and tabs. Bows were harder to tune, and clean arrow flight was not as easy with fingers.

So....the idea came about for a shorter lighter broadhead that maybe would help with speed, and hopefully have aerodynamics that fit into the whole faster arrow thing and maybe be easier to tune. And also the carbon arrow invention,...now we're cooking. AND soon then the mechanicals which were even more suited to the easy to tune for fast arrow thing, especially if you're bow was just was a bugger to get perfect arrow flight with the nock end kicking one way or the other or you did not know how to get it to not do that or you were to busy chasing girls when you weren't hunting to worry with it.

Well ....then some guys started to rethink the weight thing, some had some field archery experience and found different tip weights helped with certain aspects of arrow flight. And some guys started to notice sometimes that light arrow maybe was not all that. Especially from lower IBO bows that could not toss that thing real fast. Penetration was not always there. But to add weight with the broadhead meant going back to the longer heads which by now, were mostly what your grandpa shot

Now fast forward...bow that would tune and be fast...release aids which helped everybody start to get clean releases and not twang the string. Now some guys are starting to experiment more , wonder if I can shoot those old big long broadheads out of this thing and get good arrow flight? I always liked how they killed and penetrated. And about the same time now bows are getting so powerful, you could throw a fairly heavy arrow , with some weight in the insert AND have a big ol gnarly broadhead to boot on the end. HUH, I think this may be the best of all worlds right here.

Now, you have a mix all over the board of what people are doing, and some don't really know a lot about their arrow, other than if they stick it in the right place it usually works.

But in general, for hunting, a major trend has developed toward putting at least some weight over a lighter standard insert of say 20 grains, on your arrow. Even if you stay with a shorter lighter head of say 100 to 125 grains. Many are opting for any extra 50 to 100 grains in the insert alone. ( some less some even more).

Now ....some have also went with the bigger heads in conjunction with the heavier insert for just a lot more weight on the business end, and that longer , less acute angle , more tapered cutting edge .

And a few on occasion will use the standard weight insert and just throw a heavier broadhead on it if they take a notion.

You might want an arrow for general purpose use with a lighter insert to use for lighter game and just punching foam for a lot of the year, and then , tune it up with a big heavy head to go shoot something else with .

People build arrows now like rifle reloaders build cartridges...and a similar thing happened in the rifle rounds. First heavy and slow with big bullet, then faster and smaller , then sort of in the middle. But usually still some that are extreme on both ends, with the bigger louder camp gravitating for the heavier more stoutly constructed bullet or broadhead...

The fun to me was in the experimentation and the learning curve. Once you get it all figured out it starts to get a little more boring to me, but you're results get better...
 

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Discussion Starter · #5 ·
So, 100 grain broadhead or the 150 grain broadhead or the 200 grain broadhead.
So what?

12 grain aluminum inserts, or 50 grain brass inserts or 100 grain brass inserts.
So what?

MORE weight up front, means MORE foc (Front of Center balance).
MORE weight up front, means MORE total weight for the entire arrow.

Who cares? More total weight. Big deal, right?
MORE weight means MORE momentum. Momentum is the resistance to change direction, and resists change in speed.

THINK a freight train. A heavy freight train, moves slower but will blow through brick building after brick building, and not lose very much speed. Think economy car plowing into a tree, trying to BLOW through a tree. TREE always wins, and the economy car (less weight than a freight train) is crushed like a fly.
Thank you for your comments. This is all very helpful. I'm learning about FOC and what that means in terms of weight up front. I'm curious though, whether it makes a difference having 100 grain broad heads and a 50 or 75 grain insert, for example, versus a light insert and a 150 grain broadhead. Is it basically the same thing since the weight at the front is approximately the same, or is there some advantage to having a heavier broad head?
 

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Discussion Starter · #6 ·
Concerning mostly compounds and hunters and that evolution as I sort of saw it around here. Traditional equipment staying more true to the original form.

Long ago before the internet, and cell phones, and even before people had more than one tv set in the house.
Mostly archery was slower arrows with a more traditional longer broadhead, people where pretty satisfied shooting with something that looked somewhat like medieval armament. And honestly for those speeds and arrows it did work good. Typically a longer broadhead when made with some thought to durability its going to weigh something. If you look at the Zwickey broadheads they were popular, look at their weights. And old Chuck Adams was traveling about kicking the legs out from under about anything that walked with one of them.

Then....things started to speed up, faster arrows. Shot flatter,had a lot of peoples attention, cause many did not have or use any kind of range finder, and a misjudged yardage would have your arrow stick in the ground right under the belly of some animal and would make you're heart sink. And ....people were still shooting with fingers and tabs. Bows were harder to tune, and clean arrow flight was not as easy with fingers.

So....the idea came about for a shorter lighter broadhead that maybe would help with speed, and hopefully have aerodynamics that fit into the whole faster arrow thing and maybe be easier to tune. And also the carbon arrow invention,...now we're cooking. AND soon then the mechanicals which were even more suited to the easy to tune for fast arrow thing, especially if you're bow was just was a bugger to get perfect arrow flight with the nock end kicking one way or the other or you did not know how to get it to not do that or you were to busy chasing girls when you weren't hunting to worry with it.

Well ....then some guys started to rethink the weight thing, some had some field archery experience and found different tip weights helped with certain aspects of arrow flight. And some guys started to notice sometimes that light arrow maybe was not all that. Especially from lower IBO bows that could not toss that thing real fast. Penetration was not always there. But to add weight with the broadhead meant going back to the longer heads which by now, were mostly what your grandpa shot

Now fast forward...bow that would tune and be fast...release aids which helped everybody start to get clean releases and not twang the string. Now some guys are starting to experiment more , wonder if I can shoot those old big long broadheads out of this thing and get good arrow flight? I always liked how they killed and penetrated. And about the same time now bows are getting so powerful, you could throw a fairly heavy arrow , with some weight in the insert AND have a big ol gnarly broadhead to boot on the end. HUH, I think this may be the best of all worlds right here.

Now, you have a mix all over the board of what people are doing, and some don't really know a lot about their arrow, other than if they stick it in the right place it usually works.

But in general, for hunting, a major trend has developed toward putting at least some weight over a lighter standard insert of say 20 grains, on your arrow. Even if you stay with a shorter lighter head of say 100 to 125 grains. Many are opting for any extra 50 to 100 grains in the insert alone. ( some less some even more).

Now ....some have also went with the bigger heads in conjunction with the heavier insert for just a lot more weight on the business end, and that longer , less acute angle , more tapered cutting edge .

And a few on occasion will use the standard weight insert and just throw a heavier broadhead on it if they take a notion.

You might want an arrow for general purpose use with a lighter insert to use for lighter game and just punching foam for a lot of the year, and then , tune it up with a big heavy head to go shoot something else with .

People build arrows now like rifle reloaders build cartridges...and a similar thing happened in the rifle rounds. First heavy and slow with big bullet, then faster and smaller , then sort of in the middle. But usually still some that are extreme on both ends, with the bigger louder camp gravitating for the heavier more stoutly constructed bullet or broadhead...

The fun to me was in the experimentation and the learning curve. Once you get it all figured out it starts to get a little more boring to me, but you're results get better...
Thanks! Very helpful, especially the analogy with rifle reloaders. So far, I've killed critters fine with factory ammo, but I see the appeal.

The idea of at least some weight in front on an arrow has some intuitive appeal to me though, and seems to be what I'm reading about these days. Right now I'm just shooting basic arrows with a basic insert and a 100 grain field tip, but as I gain experience and reps and hopefully good habits, I'm looking toward getting some better arrows and broadheads for hunting in the 2022 season. It's all very interesting.

I guess I will also have to play around and see what works for me and how much weight up front makes sense. Then I guess I can figure out a balance of broadhead weight and insert?
 

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Thank you for your comments. This is all very helpful. I'm learning about FOC and what that means in terms of weight up front. I'm curious though, whether it makes a difference having 100 grain broad heads and a 50 or 75 grain insert, for example, versus a light insert and a 150 grain broadhead. Is it basically the same thing since the weight at the front is approximately the same, or is there some advantage to having a heavier broad head?
Technically, the broadhead is farther away from the nock.
Technically, the insert is a tiny bit closer to the nock.

You can balance the completed broadhead arrow on another arrow shaft (just the tube) on the dining room table.
The arrow shaft tube works like the pivot for a see-saw.
Find the balance point with the 100 grain broadhead and the 50 grain brass insert (150 grains total weight).
Find the balance point for the 150 grain broadhead and the 12 grain aluminum insert (162 grains total weight).

The balance point will not be EXACTLY the same...the balance point will move "slightly".
Will the 100 grain broadhead and 50 grain brass insert group the same at 40 yards
compared to
the 150 grain broadhead and the 12 grain aluminum insert?

Maybe. Maybe not.
Depends on how true your broadheads spin on an arrow spinner (less wobble versus more wobble).
Depends on your group size at 40 yards.

REALLY just one way to find out. Shoot arrows both ways.
 

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What bow do you have and what draw length ? Do know what diameter arrow you want to use? To build an arrow with very high FOC and not be on the really heavy end when finished...you have to start with a shaft that is lighter in grains per inch.

Each diameter arrow has some light and heavy per inch versions. Generally if you want say build a 410 to 450 grain arrow and want it to have say 14 percent front of center it will usually have to be an arrow that weighs like 7 grains per inch. And you will want to have at least say 75 grains in the insert alone, to get you there with a 100 to 125 grain head.
In typical spines of 400,340,300
A hyper light arrow will weigh 5,6,7 grains....medium weight 7-8-9 grains per inch....and heavy side 10-11-12 grains per inch...and ultra heavy on up from there.

If you start with an arrow that weighs like 11 grains per inch, but still want 15 % FOC, you will end up having to put a lot of insert,broadhead weight to get you there, and in the process make the whole arrow weigh 550 to 650 grains for example. Just need to understand a little about where you want to end up....to know where to begin. And be satisfied with your selection.

Good thing to build up a couple test arrows in three different weights and shoot them at different yardages for a while a get a grasp on what your bow can do with what arrow.
 

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Discussion Starter · #9 ·
What bow do you have and what draw length ? Do know what diameter arrow you want to use? To build an arrow with very high FOC and not be on the really heavy end when finished...you have to start with a shaft that is lighter in grains per inch.

Each diameter arrow has some light and heavy per inch versions. Generally if you want say build a 410 to 450 grain arrow and want it to have say 14 percent front of center it will usually have to be an arrow that weighs like 7 grains per inch. And you will want to have at least say 75 grains in the insert alone, to get you there with a 100 to 125 grain head.
In typical spines of 400,340,300
A hyper light arrow will weigh 5,6,7 grains....medium weight 7-8-9 grains per inch....and heavy side 10-11-12 grains per inch...and ultra heavy on up from there.
I shoot a Halon X I bought used here on AT. 30.5" draw length per the mod, closer to a 31" overall. 60lb. limbs that at max shoot 62lbs, but currently tuned down to 56lbs. Right now my few arrows are the cheap Easton 6mm carbon arrows made in China. Once I get some good practice in I want to get some hunting and/or 3D focused arrows. Currently thinking about 5mm shafts, sort of split the difference between the 4mm and the 6mm, as I am out west and will be possibly taking long(er) shots (depending on my ability). Not looking at being trendy, but want to figure out a solid arrow and broad head that will hopefully pass through game (deer for now, elk someday) for an ethical and quick kill if I do my part. I guess I'm looking to improve my form and shooting, and then figure out an arrow and setup that will give me a balanced overall profile with a moderate FOC for hunting. But I feel like it would be good to start practicing with an arrow and approximation of a setup I plan to use going forward sooner than later.
 

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Thank you for your comments. This is all very helpful. I'm learning about FOC and what that means in terms of weight up front. I'm curious though, whether it makes a difference having 100 grain broad heads and a 50 or 75 grain insert, for example, versus a light insert and a 150 grain broadhead. Is it basically the same thing since the weight at the front is approximately the same, or is there some advantage to having a heavier broad head?
The heavier broad heads are made of steel rather than aluminum, have stronger thicker blades that won't bend/fail as easily as the light ones. I prefer one made from a single billet of tool steel then hardened to at least 55Rc. Some people don't want to or can't sharpen their broad heads choose the thin replaceable blades. I shoot every broad head on the shaft then sharpen it to insure it's flight, hard to do with the lightweight mechanicals. I also prefer a heavier head instead of a heavy insert because the blade angle increases with the extra weight and the weight is moved further forward.
 
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Discussion Starter · #11 ·
Technically, the broadhead is farther away from the nock.
Technically, the insert is a tiny bit closer to the nock.

You can balance the completed broadhead arrow on another arrow shaft (just the tube) on the dining room table.
The arrow shaft tube works like the pivot for a see-saw.
Find the balance point with the 100 grain broadhead and the 50 grain brass insert (150 grains total weight).
Find the balance point for the 150 grain broadhead and the 12 grain aluminum insert (162 grains total weight).

The balance point will not be EXACTLY the same...the balance point will move "slightly".
Will the 100 grain broadhead and 50 grain brass insert group the same at 40 yards
compared to
the 150 grain broadhead and the 12 grain aluminum insert?

Maybe. Maybe not.
Depends on how true your broadheads spin on an arrow spinner (less wobble versus more wobble).
Depends on your group size at 40 yards.

REALLY just one way to find out. Shoot arrows both ways.
Thank you. That makes sense. So it all really comes down to FOC, balance, and how the arrow shoots. A heavier broadhead would move the balance slightly forward compared to a lighter broadhead and heavier insert, but otherwise maybe there isn't a huge difference.
 

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Pretty new archer so please cut me some slack. But I've been wondering about something. Is there a difference (or big difference) between say a 100 grain broad head with a 50 grain insert compared with a 150 grain broad head, for example (both in terms of how the arrow behaves in flight and how it behaves going in / through an animal)? Basically I'm wondering what the reasons are for different weight broad heads, different weight inserts, etc., and why you would choose to use one over another.
Here's how I look at it, the most common sized broadheads are 100 grains, they're easy to find, and fairly inexpensive. Insert weights are easy to find, and relatively inexpensive. 150 + grain broadheads aren't as easy to get, and cost a lot more. So for me to get the higher foc, I would rather have a 50 grain or more insert and a 100 grain broadhead.
 

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100 and 125 grain broadheads.
50 and 75 grain brass inserts.

Some combination of those things together is plenty of weight out front, and the components are pretty easy to find without breaking the budget.

If you use software like Archers Advantage you will see how the different weights on components effect overall weight, FOC, etc. Technically the further you dangle something off the end, the more the FOC goes up. It's just common sense. So a heavier broadhead will technically cause a higher FOC than the insert... but we're talking so small it doesn't matter.

Keep it simple. Stick with common components and build a basic arrow between 400-500 grains in total weight with a sharp non-mechanical broadhead that is tuned with a tuned bow. You'll be fine.
 

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A simple answer. NO. If you use a 50 grain insert and a 100 grain head , OR, a 150 grain head, then no, you want see any difference anywhere with anything. Speed , poi, flight, penetration, will all be the same. This is assuming that both are 150 grains. If you use a standard insert on the 150 grain head, then you would have a total of about 162 grains in the frond. And no, that 12 grains want net or cost you any amount to measure at 50 yards or more. In fact, I bought some broadheads from a guy awhile back. He said all 6 were 100 grains. I shot them, for practice. Shooting and sighted in a 5 pin sight out to 60 yards. All 6 arrows would hit a 3” orange dot at 60 yards. But after a few days, I was fiddling around and was weighing some arrows and components and found that the 6 broadheads were actually 10 grains difference. 3 were 100 grain and 3 were 90 grains. Yet the arrows being identical except for the weight difference of the head, they all grouped and hit same poi at 60 yards. Now further back, you would start to see a small poin change in them. But honestly, most average hunters would never know the difference , even at a 100 yards. But
 

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Arrows are rated for static spine. 340 spine arrow means in the arrow stiffness testing machine,
the supports are 28-inches part, and the arrow stiffness testing machine uses a weight (880 grams)
and then, measures the thousandths of an inch, that the arrow bends.

340 spine means that the arrow bends 0.340 inches...340 thousandths.

So, the more broadhead weight you put on the front,
the heavier the insert you install at the front of the arrow....you make the arrow behave WEAKER when you fire the arrow.

So, when the draw weight is too high...70 lbs versus 80 lbs versus say 90 lb draw weight compound bow,
the MORE the draw weight, then, you need a STIFFER behaving arrow.

The longer the draw length, then, you need a STIFFER behaving arrow.

So, say you shoot a 50 lb draw weight compound bow, and the broadheads and field points all group together at 30 yards, when you shoot a 400 spine arrow, and a 150 grain broadhead with the 50 grain brass insert. That means you have a total weight of 200 grains up front (broadhead and insert).

So, then you decide to shoot a 60 lb draw weight bow, a really FAST compound bow with say 350 fps for the IBO speed rating. So, you bump up to the 340 spine arrow, and you need to drop down to the 125 grain broadhead and the 12 grain aluminum inserts...so, you now have only 137 grains up front.

So, then, you decide to shoot a 70 lb draw weight bow, and an even FASTER compound bow with say 360 fps for the IBO speed rating. So, you bump up to the 300 spine arrow, and drop down to 100 grain broadheads and the 12 grain aluminum inserts....so now you have only 112 grains up front.

MORE speed, MORE draw weight, means you need a STIFFER arrow, and LESS weight for the broadhead, and LESS weight for the insert...to make the arrow behave STIFFER.
@nuts&bolts That makes sense, ofcourse. But the different situations that you describe, is it purely from experience or can I find the numbers somewhere? I know the spine charts of the different manufacturers, but how to determine the weight of the tip and insert is still unclear to me.
 

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My question is more of a durability issue. To me it makes more sense to pair a heavy SS insert with a heavy BH.
Just for one example: If you went after 225gr up front: A 125gr BH with a 100gr SS insert seems much stronger of a system than putting a 200Gr BH with a 25gr alumin insert.
Maybe it doesnt matter but thats my thought.
I personally use 150gr BH with 100gr SS insert
 

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N&B briefly explained 'static' spine of an arrow shaft....putting on a spine tester with a prescribe weight in the middle and measuring the deflection....the amount of bend. The stiffer the shaft, the less it will bend....the weaker the shaft, the more it will bend. Then we have 'dynamic' spine, which is a given arrow shaft being abruptly propelled forward at the nock end by a bowstring.....which applies significant force upon the stiffness of the shaft. If it is too weak, it will flex too much and not recovery quickly enough by the rudder effect of rear fins (vanes). If the stiffness is correct, it flexes a bit and quickly recovers with much higher levels of consistent accuracy. As a truism of archery, a shaft that is too stiff is better than a shaft that is too weak in spine.

The way the arrow is built....IE the components and layout of the arrow will likewise have a direct bearing on how it will fly. More or less point weight....more or less tail weight....all factor into the dynamic equation. That is how shaft companies such as Easton, GT, CX, etc base their arrow charts....they cite common arrow insert and point weights, then recommend a range of effective application. That is the middle of the road stuff.....but the pendulum of archery continues to swing and is current on the heavy end of the spectrum for a vocal segment.

You can add weight to an arrow without increasing the FOC....using a lighted nock, long vinyl cap wrap and longer or more vanes (3vs4) and arrow mass goes up. However adding weight to the rear of the shaft tends to INCREASE dynamic spine a bit, while adding weight to the front end increases FOC (as decribed by N&B) and tends to DECREASE dynamic spine. For newer folks just learning all this....or more experienced folks who were satisified screwing "X" field point/BH on to the front, sighting in and calling it good....this all seems complicated. Precisely why some tech savvy folks put together and sell subscriptions to online calculators which take the guess-work and experimentation out of the equation....mostly, but not all. Even the calculators are hitting the middle of the pack and your milage may vary.

However for some of us who have been around for a while and didn't have online programs to consult, we simply tried various combinations to see what happened. How much front weight could be added to a particular spine shaft that was cut a particular length and shot out of a particular poundage of bow. Of course the design of the cams which effects the IBO rating (maximum factory speed....often inflated) also has an effect....but that is proven out in testing.

So let's say you have a 60# draw weight compound bow with a 29" draw length.....you consult the charts and it says a 400 spine will work. But you shoot the 400 spine with a fixed BH and it doesn't fly so well....it is a bit weak. To influence dynamic spine a bit stiffer, you can: cut down the arrow shaft length (as long as it remains safe); reduce point weight; or drop the poundage of the bow. If decide none of those are desirable, the next step is to move one spine range up to a 340 spine. Now you read about FOC and want to add point weight via a heavier insert and your standard 125gr BH.....how do you know if it is going to work? Well in the olden days we took it outside and shot it. Depending upon your bow tuning method, a bare shaft at 10 yards will reveal a lot of information very quickly. If that combination flies, you can also consider leaving your standard inserts and simply raise the weight of your field point/BH. How do you know if it is going to work? Take it outside and test shoot it. But I don't want to "waste" the time and money to buy and try something that may not "work"! Well then you let others do the work and put it into an electronic program and accept their results. Your choice....learn by trial and error or follow the leader.
 

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OP IMHO you are looking at things that simply don't matter. Like the tiny differences in FOC between a insert & head vs a heavy head. These are threads that really go off into the weeds and you'd be 1000X better off putting that time into just shooting any arrow that is between 10% and 18% FOC and (for you) 380 - 500 grains and just go hunting.

I have tried in the field arrows that were very low FOC vs very high and 380 grains to 575 grains and every combo inbetween............the differences in how they kill game is there WHEN you go to the extremes for sure but even then they all worked it was just what are you really looking for? Once you get off the extremes like 425 - 475 etc and anything in between that the changes get so small you are hard pressed to see anything. At that point you are looking for niche things mostly....comfort stuff.

Your spec's of 31 inch draw 62, pounds and a newer bow even make this whole effort more pointless. So now we are debating the difference of 150 grains and how it is distributed of the last few inches of a 30 inch arrow? Think about that.

I really feel people spend a lot of time on these type things and in reality it's so detailed you'd be very hard presses to even see any difference. Pick yer' total arrow weigh, the right spine and then go with the inserts or the big head and then just tune it, shoot and hunt. You are focused way to much on one bristle in the paint brush.

Don't get me wrong I'm not a just grab an arrow and sling it guy I like to be VERY thorough and take a lot of time to dial in my hunting rig and set it up specifically for me.......that said your wasting time on things are will not make you a better hunter, get you more game or even make you a better shot. Get er' back between the white lines and start practicing. Good luck
 
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Thank you. That makes sense. So it all really comes down to FOC, balance, and how the arrow shoots. A heavier broadhead would move the balance slightly forward compared to a lighter broadhead and heavier insert, but otherwise maybe there isn't a huge difference.
When the balance point changes the pivot point of the arrow in flight when receiving interference changes, but how much that change affects overall accuracy and penetration and such is math that's beyond my simple, crayon-eating Marine brain. The best way I can think of to explain it is to think of the arrow as a vehicle that turns with its rear wheels. Like a forklift. The balance point is the front pair of wheels that it pivots on. Whether that balance point is a little further forward or back will change how sharply the vehicle can turn, but how much you need or want is highly subjective and usually a personal choice. Some people are happy with none, some people want it all, most people are in the middle.
 

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Thank you. That makes sense. So it all really comes down to FOC, balance, and how the arrow shoots. A heavier broadhead would move the balance slightly forward compared to a lighter broadhead and heavier insert, but otherwise maybe there isn't a huge difference.
@nuts&bolts That makes sense, ofcourse. But the different situations that you describe, is it purely from experience or can I find the numbers somewhere? I know the spine charts of the different manufacturers, but how to determine the weight of the tip and insert is still unclear to me.
Simply an example to demonstrate the concept. You can purchase Archery Software that will calculate all of this for you. Pull down menus for every brand and model of arrow, will have the weight per inch, will have the static spine rating, and will calculate the dynamic spine reaction for any point (brand and model), for any vane (brand and model), for any insert (standard aluminum, or optional brass), for any nock (push in nock, pin nock, lighted nock).
 
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