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View Full Version : Lighter Broadheads vs Accuracy?



brotherjack
09-10-2005, 01:41 PM
So, the arrows I've been shooting this season out of my Horton SteelForce have been pretty heavy (total arrow weight just under 500 grains). The factory arrows are total weight like 385 grains. So, heavier is better for KE and bow life, but worse for trajectory. Flatter trajectory is better for well placed shots, which is more important than KE for a kill shot (presuming you have somewhat adequate KE).

Anyway, long and short of it is, after deciding I'd like flatter trajectory, and not wanting to go back to the ultra-light/small fletching/too short factory arrows (garbage for accuracy), I'm thinking real seriously about sticking with my longer/heavier carbon arrows, but going to a much lighter broadhead, like to a 75 to 85 grain (Muzzy or Montec - still debating with myself), which would get me to around 440-ish grains total arrow weight.

So, before I go spend the money, question for you more experienced folks - is there any concerns to be aware of regarding using ultra-light heads on relatively heavy arrows? Any accuracy issues? Other issues? Thoughts? Would I be better to stick with my 125 grain Muzzy's and use a lighter arrow?

Thanks for any input or advice.

Kirby
09-10-2005, 05:28 PM
I use 2 broadheads mostly, and am experimenting with a 3rd righ now, they are 85gr thunderheads, 90gr 4 blade muzzy, and am playing with 85gr spit-fires. I have never had a problem shooting lighter heads. Personally, I say go for what you are most confidant with. Test out some 85gr tips, and check to see how much of a difference they make, then decide.

Kirby

Tuffcity
09-10-2005, 06:20 PM
Flatter trajectory is better for well placed shots

Personally I'd go with more practice for well placed shots. It looks like you're going for short cuts for success. How far out are you trying to hit animals? If you're pushing past 40-50 yds (which I think is really stretching things) maybe go back to guns.

Short version: stay with the heavier arrows (bolts) If the trajectory is dropping off at the ranges you're trying to hit animals with then get closer.

OK, curiousity is getting the better of me so I have to ask: did you pick up a cross gun just for the extended season or do you like to get up close and personal with the prey? Do you practice with it or does it hang in the closet once the season closes? I'm not trying to slag you (with the internet not being the best media to convey what one trys to say) but the impression I get is that you're new to the archery game and trying for the quick fix over a practice regime.

If I'm way off base then you have my apologies, if not, then slow down, work with your weapon and find the limitations and accept them.

If you still bent on going lighter don't do it on the front end. You need a decent FOC (forward of centre) weight or it will cause all manner of tuning grief. I've never used X-bow so I'm not sure how severe it would be with too light a tip-especially with a short shaft, but my recurve likes about 15% FOC on a 31.5" shaft. After playing around with different FOC's I know it gets really squirrely flight under about 7%

RC

brotherjack
09-10-2005, 08:21 PM
How far out are you trying to hit animals?

Short version: stay with the heavier arrows (bolts) If the trajectory is dropping off at the ranges you're trying to hit animals with then get closer.

OK, curiousity is getting the better of me so I have to ask: did you pick up a cross gun just for the extended season or do you like to get up close and personal with the prey? Do you practice with it or does it hang in the closet once the season closes?

If you still bent on going lighter don't do it on the front end. You need a decent FOC

Yeah, I am 100% new to crossbows and bowhunting. I got a crossbow instead of a u-pull-it, largely because my wife hunts with me, and can't pull a 40lb string (at least not well enough to practice and get proficient with it). The inexpensive-ness of it also appealed to me - I'm officially poor, and $129.99 US on eBay was a lot nicer than around $350 for a cheap compound bow with decent sights and such.

I was not, and am not under any illusions as to the limitations (or lack thereof) of the weapon - it's a very short bow on the end of a stick; complete with all the yardage and accuracy limitations of a u-pull-it, as well as a few of it's own because of the short arrows and high poundage required to get decent velocity.

The Wife and I put in a LOT of practice getting ready for the season. We shot in the backyard till the string was almost wore out and my back was killing me before either of us ever pointed it at an animal. 25 to 50 shots a day, one arrow only - walk up and retrieve, and start over (because you don't get a second shot to tighten up your aim in the field).

Anyway, the reason I'm interested in a flatter trajectory, is that with the heavy arrows on the 150lb SteelForce with it's relatively short powerstroke, my trajectory is harsh even at 20 yards. The difference between even close distances like 5 and 15 yards is about 6 inches. By the time you hit 20, it's another 6 inches, and another 6 inches by 25 and so-on. Judging 5 yard differences in the field is significnatly more difficult than judging 10 yard differences. A heavy arrow like 500 grains at a relatively slow 200FPS just drops hard - it's a fact.

I have a personal limit I have set of 30 yards for my longest shot. In practice, there's been no danger of getting even remotely close to that - the farthest I've ever shot an animal from is 15 yards. I actually lost an animal this year because I shot it from about 3 to 5 yards away, and my sight was set for 15 yards - arrow through the backstraps - I hated that. But I like up close and personal. I like it a lot. I'm probably going to rifle hunt using a lot of the same techniques I've learned while out with the bow for just that reason.

Anyway, in practice, with the 300-some grain factory arrows, the trajectory is almost flat to 20 yards, although the accuracy is awful - the stock arrows are too short (17"), too light for a 150lb snap, and the fletchings too itty-bitty to properly control flightpath after the violence of the launch. If you put the bow in a vice, and cocked it with a machine, I bet it'd still not plant better than 6 inch groups at 25 yards with the stock arrows. They're that bad. I can split nocks with the heavy 20" carbon arrows, so I'm pretty sure that the accuracy issues are the arrow and not the bow.

What I am looking to achieve, is a more graceful medium. Significant arrow drop at 10 yard intervals instead of 5 would take a LOT of the headaches out of trying to judge yardage in the field. In reality, what I am probably needing is a significantly faster shooting, higher quality bow - but refer to the early statement about being officially poor. :)

Thanks for your time,

greybark
09-10-2005, 09:41 PM
Hey Brotherjack , I agree with Tuffcity in regards to 15% FOC and don`t for sure but i would think the shorter the bolt the more critical the FOC. The Easton arrow charts explain how to figure out it out .
I appreciate you attitude in putting to use your new knowledge and you practice ethics.
Good luck to you.
P.S. Did we met on the Morrisy rd (near there) just before archery season . You had an "A fram" camping trailer.

REMEMBER -- Keep Your Fingertab On --

Tuffcity
09-10-2005, 10:10 PM
I appreciate your candor. Some people get into archery for the wrong reasons, particularly a cross bow because it's a set the scope and go, no practice required... or so they think.

Your last post certainly sets you apart from that crowd.

I can sympathize with rainbow trajectory, I shoot an arrow that weighs around 600gr from a 55# recurve. It's probably moving about 190 f/s. Except that my brain does the auto hold over calculations (shot instictively) so I'm not relying on a site pin. Not really applicable to your situation however. :)

I'd still suggest that you stay with heavier and more accurate versus light and better trajectory. Mainly because I think you'll find that mometum ( mass X velocity ) is a better indicator of arrow effectiveness than KE. ( ½ mv2 )

If you hunt from elevated stands you can always discreetly mark your yardages for better ranging.

RC

Fred
09-10-2005, 10:41 PM
I just picked up BCHunters Barnett RC150 and was comparing your comments to the instructions on the Barnett site.
As I am fletching and preping my own arrows already(for my Mathews Feathermax) I have a bit more insight into what may or may not be required. Well, at least I think so!;-)
The Barnett has 5 inch vanes compared to my usual 3 inch. This probably helps to stabilize the short 16 inch bolts.
Also they recommend not going lower in weight than the "as supplied" bolt weights to help avoid potential disasters. They also recommend using only aluminum(not wood) and I can't help but wonder if Carbons would hold up to the much higher poundage of the crossbow.
I read somewhere on the Barnett site that their arrows for the RC150 were 3hundred and something in weight(375?). They also recommend a 125gr field tip or hunting tip. It seems to me that a weight somewhere between the factory standard and your 500gr would work better for you. For myself a bit of experimenting is in order with my Chrony and the first thing I will try is removing the 22 scope off of this Barnett. I just can't get far enough away fron it to get a decent sight picture. Fred

brotherjack
09-11-2005, 04:56 PM
P.S. Did we met on the Morrisy rd (near there) just before archery season . You had an "A fram" camping trailer.


I don't think so. I don't know where Morrisy road is, and I don't have a camping trailer. I'm either a 4dr dark purple Chevy Tracker with monster mud tires, or a red 4x4 Ford F150 (junker) with an old cab-over slide-in camper.

brotherjack
09-11-2005, 05:19 PM
I can sympathize with rainbow trajectory, I shoot an arrow that weighs around 600gr from a 55# recurve. It's probably moving about 190 f/s.

I'd still suggest that you stay with heavier and more accurate versus light and better trajectory. Mainly because I think you'll find that mometum ( mass X velocity ) is a better indicator of arrow effectiveness than KE. ( ½ mv2 )


I agree with the "more force is better" theory, up to the point where there's very adequate force. After that, it seems to me that having the flatter trajectory has a bigger payback than the extra force of the heavier arrow.

I'm thinking this way after my experience to date - my initial thought was that I wanted the heaviest thing I could shoot reasonably out of the SteelForce.

Really, what I'd like, is to go pickup about a 175lb Excalibur and stick with the heavier arrows, but I don't have that kind of money available, so I'm trying to work with what I got.

brotherjack
09-11-2005, 05:27 PM
The Barnett has 5 inch vanes compared to my usual 3 inch. This probably helps to stabilize the short 16 inch bolts.


Yeah, for whatever reason, the Horton shipped with fletchings that are like 2 inches long, and small to boot. The picture on the box shows fletchings twice the size they are on the ones I got.



Also they recommend not going lower in weight than the "as supplied" bolt weights to help avoid potential disasters. They also recommend using only aluminum(not wood) and I can't help but wonder if Carbons would hold up to the much higher poundage of the crossbow.


The carbon's should be fine. I've shot 3 of mine half to death, and not the first sign of any problem out of them. (I've got 3 more I only use for hunting).



I read somewhere on the Barnett site that their arrows for the RC150 were 3hundred and something in weight(375?). They also recommend a 125gr field tip or hunting tip. It seems to me that a weight somewhere between the factory standard and your 500gr would work better for you. For myself a bit of experimenting is in order with my Chrony and the first thing I will try is removing the 22 scope off of this Barnett. I just can't get far enough away fron it to get a decent sight picture. Fred

Yeah, I think about 50 grains lighter, but sticking with the 20" arrow and longer fletchings would do pretty good for me.

You might like a red dot scope too. That's what I got on mine, and I love it. It's like having a lazer sight basically. They make one with 3 dots at different ranges specificly for crossbows.

Fred
09-11-2005, 10:56 PM
I had a bit of a look see at those red dots but the price would likely put me off!:mrgreen: I will try extended rings first on this little 22 scope. Fred

brotherjack
09-19-2005, 02:24 PM
UPDATE:

So, after rewinding my serving with fishing line (becuase I'm too lazy and poor to order a new string just because the serving's worn out), I got down to some field testing on this topic. Here's my results using a 125 and 100 grain field point on identical Horton MX carbon arrows.

2 yards - no noticeable difference.

10 yards - about 2 inches higher with the 100 grain.

15 yards - about 4 inches higher with the 100 grain.

20 yards - about 7 inches high with the 100 grain.

25 yards - about 9 inches high with ther 100 grain.


So, 25 grains less definitely results in a MUCH flatter trajectory at close range. I didn't test any farther out than that - that's my self imposed hunting limit anyway.

Balancing the two arrows across an edge, the FOC looks to be moved rearward about a quarter an inch because of the lighter heads. This did not seem to affect accuracy in the slightest. That said however, the 100 grainer consistently pulled about 1 inch to the right compared to the 125, but as long as any differences are consistent, I don't consdier that accuracy affecting - I can just adjust the sight to compensate.

The better news in all this is, with the dial-a-range setting on the crossbow set to 0 (point blank range, in theory), and the 100 grain point, I can shoot out to 20 yards and be within 2 inches of the point of aim (about 2 high at 2 yards, and 1 low at 20 yards).

This is EXACTLY what I was hoping for.

Anyway, just thought some of you might find my results useful. For reference, the bow is a Horton SteelForce 150lb.

If I get ambitious, I may grind down a field point to around 75-85 grains, and see if that improves things further, or just wonks up accuracy. But probably, I'm thinking I'll get what I'm after by just dropping back to a 100 grain head from a 125.

brotherjack
09-20-2005, 10:23 AM
More Update:

So, I took a 125 grain field point, a vise, and an angle grinder, and cut it down a bit. Ended up with a head that was 4 grams (60-something grains), which is lighter than I was going for (I was trying to get one around 5grams/80grains). However, I didn't want to cut up another one, and I thought it would be reasonable for testing purposes, so I gave it a whirl.

This one moves the balance point of the arrow to the rear just under 3/4 of an inch from the 125 grain point.

At closer ranges (20 yards or so), the accuracy seemed to be fine. No noticeable drift compared to an arrow with a 100 grain head on it.

However, at 30 yards, I did notice it drifting a bit (2 inches approx). Still not enough to botch a well aimed kill shot, but enough to be noteworthy.

The trajectory, again, improved dramaticly. It broght my effective range with the sights set on 0 (point blank) out to nearly 30 yards. Yeah!


So, in conclusion, I'm planning to do the following:

Switch from vanes to feathers (about 10 grains less at the rear of the arrow).

Switch from 125 grain 4 blade Muzzy's to 75 grain 3 blade Muzzy's. (I was originally thinking about going to a 90 grain 4 blade, but I think the 75 grain 3 blade will suit me better).

I'm assuming, that since even with a 60 grain head, the arrow accuracy wasn't affected too badly, that loosing 10 grains in the back and having an extra 15 in the front will tighten that up.

Anyway, no idea if anyone else will find this useful or not, but here it is, for whatever it's worth. :)