Broadhead Weight Tolerances

[NullPointerException]

Hi all,

So I'm about to broadhead tune my bow, which will hopefully just consist of screwing on a broadhead and watching it group with my field points. I am using a model of broadhead that got redesigned this year. I have a bunch of leftovers from last year of the old design and just ordered a batch of the new design. Both heads look nearly identical (in theory both should fly the same), but the newer design is advertised as having more penetration. Also, the marketing folks say you can change out the blades to convert from old to new.

I should also mention that I have enough heads from the old design to last me my first hunt and maybe through the entire year if I never miss. The more likely scenario is I never get into bow range of an animal, but that's a different story.

I just got in my newly redesigned heads and saw something. The ferrule on them is cut differently, so a blade swap on my new heads will still not result in exactly the same head (shouldn't make a difference in terms of flight, but worth noting). It looks like the newer head's ferrule is milled out a bit more towards the tip for whatever reason. Sure enough, when I weigh the new heads (tested three and all were consistent) I get 123 grains, not 125 grains. Truth be told my old heads were a little light, but were around 124.5 grains.

Given the situation, I'm wondering what I should do. My first hunt of the year is in 10 days. I'm less concerned with penetration, but more concerned with consistent arrow flight out to distance since I'm hunting antelope. Does a whopping two grains matter? Should I just test/tune both sets of broadheads to ensure both fly like they should?

 

[rustednuts]

2grns is not going to make a difference. I weight match components when building arrows to not have massive weight variance.

 

[seeth07]

Probably your at what, a total grain arrow of 475? 2 grain difference is nothing.

 

[WapitiBob]

2 grains isn’t much but overall aerodynamics can be different. I’d shoot at least one of each and see, somewhere 50-60 yards.

 

[Mtnhunter1]

I'd say, shoot the new heads! If they fly true, then the grouping will be up to you and your shooting form.

Curious about your statement: " but more concerned with consistent arrow flight out to distance since I'm hunting antelope." what is the out to distance mean?

 

[NullPointerException]

I'd say, shoot the new heads! If they fly true, then the grouping will be up to you and your shooting form.

Curious about your statement: " but more concerned with consistent arrow flight out to distance since I'm hunting antelope." what is the out to distance mean?

I just want to make sure all arrows (field points, old style broadhead, new style broadhead) group together at my maximum effective range. My primary concern is that speed goats are relatively small bodied and I don't want to find out that my field points group in the center, old style heads 3'' high and new style heads 3'' low (ok, this is an extreme example).

 

[NullPointerException]

Appreciate all the replies. To give my OCD a rest I think I'll shoot one of each head out to 50 yards. I think I just need to convince myself that this is a non-variable. Come to think of it, last year I shot both a fixed blade and mechanical and both grouped in the same spot (human error was the cause of group size). I guess if the bow is tuned, this should be a non-issue.

 

[Mtnhunter1]

You should shoot both new and old at the same time and see if there is a difference in flight. I would expect that you will see zero difference. As far as getting your field points and broadheads to shooting to the same hole? You won't be hunting with your field points so dial in your broadheads and go hunting! I should say that I have not shot a field point in decades. My bows are for hunting, so I dial everything in with broadheads.

Good Luck with your antelope hunt and try not to stretch your shot yardage in the open country.

 

[NullPointerException]

Alright, I got some updates.

Poked the manufacturer. The 2 grains is by design to make the heads fly more like field points. Many broadheads will hit low at longer distances due to the increased drag. By making the head slightly lighter, they are trying to make up for that.

Shot both designs yesterday out to 50 (this is my max distance for antelope). The last three shots with the new design were 1'' left/high (40 yards), bullseye (40 yards), 3'' high (held for 50 yards, block was actually at 49 after ranging and the release didn't feel great). I'm confident that the new design flies well. If I had to make my arrows right now, I'd build them all of the new design.

The old design had issues. I first shot it at 20 yards (always making sure I'm going to hit the block first) and it hit an inch left. It was probably me. I then stepped back to 30 and 40 yards and had all sorts of fun. Despite focusing on each shot (learned my lesson at 20), I was getting misses 5-6'' to the left or right. I was about to start messing with my rest when I stopped myself and began thinking logically how both designs are similar enough to where I couldn't explain the erratic flight. So I began looking at the arrow and sure enough, the old design had deformed at some point (it looks like a helical vane!). I shoot a four fletch, so based on how I had the arrow nocked, I'm thinking that explained the left/right misses. I'm not too confident in the old design now (deforming in foam?!?!?!) and will probably build up all my arrows using the new heads.

Here's what I think might be the culprit (in order of what I think is going on):
1. Deformed head
2. There was something about the arrow that I screwed the old design onto
3. My bow is incredibly out of tune to where the old design flies differently (had a pro shop tune it in mid June)

I should also mention that my OCD meant that each arrow I used for testing was spin tested and indexed the exact same way (i.e., how the blades are in relation to the vanes).

At any rate, I have some more testing to do tomorrow morning. I don't get out there until this Thursday.

 

[NullPointerException]

My OCD has been cured. Both head designs fly great, as long as I do my part.