Point weight isn’t always what you’d think

[LookMomNoSights]

    I’m only posting this as not long ago,  there was a conversation about point weight matched between broadhead and field point and how some or many can find themselves going the extra mile to make those 2 numbers match dead on.  I think we all head straight for that goal as it should make sense...... however many grains up front that makes an arrow fly true is what you go with and should yield great results barring all other things being sound.
Well,  recently got a new bow,  different poundage than usual,  time to tune some carbon:  after tinkering for a couple weeks with the finest details and bare shafting adnauseam,  I was getting satisfying results (essentially perfect) with a 500 spine arrow cut to 29.25 inches with 200 grains of point. I draw 27 and drawing 46# at that 27 with this new bow.  Practically perfect arrow flight with accuracy past 20 yards, before fletching.  So I’m shooting lots with complete arrows and stretching it out to and a little past the 40 yrd mark and I’m 100 percent confident I built the right arrow.   Time to go to broadheads:  160 VPA 3 blade on the long aluminum adapter gives me a matching point weight to my field points - 201 grains.  They shoot pretty good,  but I feel they could be a touch better to show lights out on the target.  For grins,  I take the same broadhead glued to a 75 gr STEEL adapter from another arrow,  check the spin, spins perfectly........ shoot.....dead nuts on perfect and the sound is even a bit different-better!  more of a heavy thud at release vs a slightly sharper thud sound.  I’m honestly a bit intrigued by that detail.
This is a 35 grain point weight difference....... accuracy is dead on with both arrows,  field point and broadhead,  but 2 different point weights. Trajectory is no different between the 2 out to 35 yrds...... a distance I’m not going to shoot animals at.  All other details with tuning and my form, release everything, is on point.    I guess what I want to convey with regard to point weight matching,  is to not always get hung up on that ..... broadheads that fly true and don’t have a drastically different trajectory,  is the goal.  And it’s not always going to be an exact match to your field point.

[Baylee]

Broadheads do not fly exactly like field points no matter how many people say they do.

[Terry Green]

Broadheads do not fly exactly like field points no matter how many people say they do.

False.

[McDave]

My personal experience is that increasing the point weight of an already heavy point has less effect on tuning than increasing the point weight of a lighter point.  You increased the point weight of a 200 grain point by 35 grains and didn't notice much effect on tuning, which jives with my own experience.  However, increasing the point weight of a 100 grain point by 35 grains would have a substantial effect on tuning.

My THEORY is that the effect of a weight change of the arrow point on tuning is more proportionate than absolute.  Your 35 grain increase in point weight was a 17.5% increase over your original 200 grain point.  If I increased the point weight of a 100 grain point by 17.5%, I would have a 117.5 grain point, which in my experience would show close to the same effect on tuning as your adding 35 grains to your 200 grain point.

I don't know if my theory is true, but I would be interested to know if any others have experienced the same effect.

[LookMomNoSights]

Broadheads do not fly exactly like field points no matter how many people say they do.

False.

Terry I think I know what you are getting at and if so I definitely agree.... that you can get your broadhead to fly like your field points..... as in being just as accurate and of flight identical to your field point... as they should be.  As I managed to do with the tuning I talked about in the original post.
Took some experimenting and lots of shooting to confirm,  but accomplished.  I can shoot a 200 field point and put the broadhead on the same spot with the next shot and both arrows fly exactly the same.

[Terry Green]

Eric just one case in point of many I could describe....

I was in my back yard once shooting at a thick latex block target from roughly 20 yards with a sharpened 140 grain Snuffer to 135 grains with a long aluminum adapter of 42 grains = 177 grains.

I shot the arrow into the target and the glue gave way and the Snuffer stayed in the target.  Not wanting to destroy any other Snuffers, I picked up an arrow with a 175 grain head on it and shot at the same spot I was aiming at with the Snuffer. When I went to pull the 2nd arrow is was rather hard coming out not like a field point.  The field point had entered the Snuffers furrel to the point of bulging it and making it so tight that it stayed on the field tip.

This was posted here on Tradgang years ago, I have no idea what thread its on.

My 175 grain Judos fly the same also.

[Friend]

McDave…Have consistently experienced proportionate front wt changes as having predictable results

^^^Have often had tuned bare shafts at 20 yards that would exhibit poor tune with BH tipped fletched arrows

^^^Have had 100% positive results when bare shaft tuned to 40 yards then switching to BH tipped fletched arrows that were shot to 35 yards.

^^^Today, I may just rough in my bare shaft tune to 25 yards and go straight for my BH tipped arrow and tune to 35 yards…If possible, I will go straight to BH tipped fletched shafts and tune to 35 yards.

The tune of the BH tipped shaft is the one and only requirement that secures my confidence level.

[George Tsoukalas]

I don't shoot carbon arrows so just saying that I am not versed in tuning them. Typically, arrows are tuned with broad heads and then that translates to field points.

Just wondering how a 235 grain field point would fly.

Jawge

[LookMomNoSights]

My personal experience is that increasing the point weight of an already heavy point has less effect on tuning than increasing the point weight of a lighter point.  You increased the point weight of a 200 grain point by 35 grains and didn't notice much effect on tuning, which jives with my own experience.  However, increasing the point weight of a 100 grain point by 35 grains would have a substantial effect on tuning.

My THEORY is that the effect of a weight change of the arrow point on tuning is more proportionate than absolute.  Your 35 grain increase in point weight was a 17.5% increase over your original 200 grain point.  If I increased the point weight of a 100 grain point by 17.5%, I would have a 117.5 grain point, which in my experience would show close to the same effect on tuning as your adding 35 grains to your 200 grain point.

I don't know if my theory is true, but I would be interested to know if any others have experienced the same effect.

David,  I would be interested as well...... have to have experiences from folks through a range of draw weights to tell I suppose. I just can’t help but think that lots of folks once they would approach a weight difference exceeding that 20 grains or so,  might abandon ship and go to plan B without the actual testing to prove a set up doesn’t work?   It’s an interesting thing anyhow 

[Wapiti Chaser]

McDave what you stated makes perfect sense !

[Orion]

McDave.  Makes sense and agrees with what LookMom demonstrated.  That is that a relatively small, and sometimes not so small, change in point weight often doesn't make any difference on arrow flight. So we shouldn't get so up tight about a few grains one way or the other.   

[Stringwacker]

I read years ago an article by Roger Rothhaar and in it he stated that the broadhead eight should be about 25 grains less than a field point  to match the same arrow tune. The longer overall arrow length in conjunction with the additional weight shifted forward results in a slightly weakening of dynamic spine.

While I can't say its always 25 grains difference, I can say the broadhead weight always need to be less in my particular shooting style. Frankly, its usually not enough to notice but if you want to shoot a perfect single bareshaft; you need less broadhead weight. I test that by first tuning to a perfect tune with a field point; then wetting the feathers (or cutting the feathers to the quill) on a broadhead tipped arrow and shooting it to compare. I usually need to move my nock point slightly up as well.

[Dave Lay]

I read years ago an article by Roger Rothhaar and in it he stated that the broadhead eight should be about 25 grains less than a field point  to match the same arrow tune. The longer overall arrow length in conjunction with the additional weight shifted forward results in a slightly weakening of dynamic spine.

While I can't say its always 25 grains difference, I can say the broadhead weight always need to be less in my particular shooting style. Frankly, its usually not enough to notice but if you want to shoot a perfect single bareshaft; you need less broadhead weight. I test that by first tuning to a perfect tune with a field point; then wetting the feathers (or cutting the feathers to the quill) on a broadhead tipped arrow and shooting it to compare. I usually need to move my nock point slightly up as well.

Mark, I agree 100% the over all length is a factor no one is talking about although the OP is having the opposite findings by going to a heavier BH
Rather than a lighter one which would make sense to me

[Stringwacker]

I think we are talking about two different things. The OP has went up on his point weight, still has good arrow flight, impacts the same, and like the thump of the heavier weight better. There is a great amount of latitude in tuning and still achieving good flight with arrows. For example, a dozen of very good wood arrows has a 5 pound spine variance.... and still spins perfectly on its axis in flight when you have the right spine grouping for your bow

I was talking about what I see when I use a single bareshaft method on arrow tuning. Broadheads always bareshaft tune to a less weight than a field point...at least with what I have found for 30+ years. I can't say the results can't vary though. I take a little comfort knowing I'm in the middle of the sweet spot in arrow tune and nock height when shooting broadheads. It doesn't mean I couldn't add maybe 50 more grains and still make it work.

Does it really matter if the arrow shoots well and hits where you aim?...probably not. I'm just approaching arrow tuning with the precision of a scalpel.... vs that of a meat clever.

[trad_bowhunter1965]

Eric just one case in point of many I could describe....

I was in my back yard once shooting at a thick latex block target from roughly 20 yards with a sharpened 140 grain Snuffer to 135 grains with a long aluminum adapter of 42 grains = 177 grains.

I shot the arrow into the target and the glue gave way and the Snuffer stayed in the target.  Not wanting to destroy any other Snuffers, I picked up an arrow with a 175 grain head on it and shot at the same spot I was aiming at with the Snuffer. When I went to pull the 2nd arrow is was rather hard coming out not like a field point.  The field point had entered the Snuffers furrel to the point of bulging it and making it so tight that it stayed on the field tip.

This was posted here on Tradgang years ago, I have no idea what thread its on.

My 175 grain Judos fly the same also.

When you can do that twice in a row let me know lol.
Other than luck a 145 grain field point does not fly exactly like a 145 grain 3” long Broadhead. If you have to “tune” anything or adjust anything they ain’t flying exactly the same. It might not be enough of a difference at 15 yards but it’s not identical.

Well I am no expert but I have been shooting for over 40 + years both Trad and compound and I can tell you from my experience that if my bow is tuned to my arrows and my arrows are spinning perfect it doesn't matter how long the broadhead is as long as it is the same weight as my field points or judo point they hit the same spot. And right now I am shooting 3 difference broadheads all 160gr Grizzly, Wolverine and a Bear and they all hit the same as my field point. 
 

[RIVERWOLF]

Just an opinion
but several Good Points being made.  The more inital point weight needed should equate to less effect with small amouts of "point weight" changes. Sounds logical to me   Which would wager  that a lesser initial point weight would likely lead to more exagerated effects in smaller weight changes to the point weight. Same as with lighter weight arrows in my  thinking.

I would also be in full agreement with  Terry and others that good arrow flight with field points and matching weight broadheads should be the same....(If not , and they are mounted "true" )you have been walking (shooting) a very fine line of exceptable spine for your rig . So fine that VERY MINOR variances in form-release-etc.. have LARGE/great effect on that fine line .....With the "BEST" spined shaft choice you should have a wider (the widest degree of exceptable change ) SAFE ZONE if you will where that spine combination is most tolerable of small changes. If that makes any sense ;^)))

[LookMomNoSights]

Eric just one case in point of many I could describe....

I was in my back yard once shooting at a thick latex block target from roughly 20 yards with a sharpened 140 grain Snuffer to 135 grains with a long aluminum adapter of 42 grains = 177 grains.

I shot the arrow into the target and the glue gave way and the Snuffer stayed in the target.  Not wanting to destroy any other Snuffers, I picked up an arrow with a 175 grain head on it and shot at the same spot I was aiming at with the Snuffer. When I went to pull the 2nd arrow is was rather hard coming out not like a field point.  The field point had entered the Snuffers furrel to the point of bulging it and making it so tight that it stayed on the field tip.

This was posted here on Tradgang years ago, I have no idea what thread its on.

My 175 grain Judos fly the same also.

When you can do that twice in a row let me know lol.
Other than luck a 145 grain field point does not fly exactly like a 145 grain 3” long Broadhead. If you have to “tune” anything or adjust anything they ain’t flying exactly the same. It might not be enough of a difference at 15 yards but it’s not identical.

If we are being literal with "flying",  I'd say yeah .....so flying is the action of the arrow moving from the bow to the target.  POINT OF IMPACT is a great deal of what folks are roping into "flying",  when we talk about how an arrow will fly.  Bottom line is if you got a field point that you drill bullseyes with,  and an arrow with a broadhead that you drill the same bulleyes with,  your broadhead arrow is flying (impacting) identical to your field point - the desired result - regardless of adjustments with the arrow and point weight and such.  I'd venture to guess that in many instances, your field point weight will not exactly match your broadhead weight for the broadhead arrows that will fly and hit where you need,  which was pretty much the point of the original post.

[GCook]

I disagree.
 If I do my tuning well any broadhead of the same weight, regardless of length or width, will fly the same as the field point weight I tuned with.  Or blunt or judo or . . .

[Dave Lay]

Stringwhacker, Mark I guess I’ve never gotten that precise with bareshafting , I bareshaft with what field point weight I want in a broadhead, get it as perfect as possible with my crappy release , put the broadheads on, then fletch em with 5” , shoot em to check flight and go hunt  that’s about as precise as I can get. Lol

[Stringwacker]

Dave,  your method seems to work for well for 99.99% of the folks!

I just like to take things to extreme. I should have stated the only way to tune an arrow properly is start by knowing the natural rotation of the arrow out of the bow.... so that you know whether to use right or left feathers when you eventually fletch

Seriously, I just like 'playing' with arrows. Hopefully, you can make it to my place this year so you can see just how eccentric I can be:)