jebo0420

I have decided to switch from a traditional mechanical head to the 2 blade bloodrunner. While making that switch I also changed from a standard d loop to a "torqless" loop. I can group my field points out to 40yards no problem, walk back is a line up and down but my broadheads land in roughly a 10in group. I tried to make moves to bring the broadheads to my fieldpoints but I just end up changing my fieldpoints impact as well, not improving my impact for both. Question is could I be having a spine issue?, I'm scratching my head... any insight will be appreciated.

BGfisher

It could be a spine issue, but there is no way of telling as you haven't listed the details of your setup.

How is your broadhead group scattered? Up? Down? All over?

jebo0420

sorry, bow is an 09 stinger 70lb. draw, replaced strings with vapertrails bout 2 years ago. whisker bisket, truglo range finder single pin, arrows are carbon express termiantors 6075, arrows are cut to 27.5 and my draw is set at 29. there is no consistent group "to the right,left,up,down" maybe if any low right. I've checked for fletch contact with powder on the riser...nothing? I may just borrow some different heads to see if maybe it's the new heads I'm trying... I'm trying to improve my kinetic transfer down range. I lost a deer 2 years ago, and almost an other this year because of poor blood trails and I figured Insuring a double pass thur would definitely help those, neither deer had one at 30yds. One I'll place blame on the broadhead, this year I have to blame the bow or the set I have. That's the only reason I'm tweaking my set up. I would love to buy one of the newer bows with more speed, not to say what I have now won't work just never want to have that experience again of not finding an animal.

bronko22000

If you are adjusting your rest to get your broadheads closer to your field tips then you field tips WILL change their point of impact as well. If you cannot get your BHs and FTs to hit at or very close to same POI than you likely do have either a spine issue or fletching contact issue.
Just FYI - I was having the same problem with my PSE DNA. Shooting the same draw weight and draw length and same arrows as my Martin Firecat. I finally resolved this by going to a heavier spined shaft. I can only surmise that PSE shoots a much faster arrow with a more radical cam which required the stiffer arrow.

jebo0420

thank you for the response, I figured as much. The more I dig into this sport the less I realize I know, lol. On a side note has anyone had any experience with the Easton full metal jackets?

super_hunt54

Okay, I'm digging this post up from the grave I know. If your BH's are the same weight as your field tips then no it is not a spine issue. If say you are shooting 100gr field tips and 100gr Broadhead's then how could it be a spine issue if the field tips are shooting consistently? It's the broadhead's themselves that fly crappy. You aren't the first one to complain about this particular BH planing at past 30 yards and grouping poorly. The company tries to say that they will fly true to field tips with no "BH to Fletching tuning" but that is total horse pucky. Very few, if any, 2 blade fixed blades fly well without tuning. It's the nature of the beast with them.

bronko22000

super-hunt there are a couple flaws in your logic. It can be a spine issue that is magnified by the BHs. As I previously posted, I had the same problem. Second, there is no evidence that 'tuning' BHs to fletching improves flight. It is a myth. If your bow is tuned to properly spined arrows and your BHs are aligned (ala spin check) you will not have a flight problem - period. I shot various 2 blade BHs with excellent results including Bloodrunners.
I would bet that if this guy went up to the next stiffer arrow, did a bit of tweaking, his bow would shoot better than he can hold.

super_hunt54

Like hell it's a myth. 2 blade fixed heads can and will "fight" your fletchings. I have been an archer for well over 40 years, and have seen it many more times than I can remember. Now granted I didn't think about the spine issue but I know full well it is NOT a spine issue because he is having this problem at 40 yards. At 20 yards an improperly tuned bow or improperly spined arrow may have a little forgiveness with a field tip and group well but NOT at 40. If he is grouping well at 40 with the field tip then he will group well with the broadhead if he is not having a STEERING problem! It's simple as that. Tuning your 2 blade to fit well into the helical of your fletchings will 90% of the time solve this issue. The other 10% of the time it is usually because you are "under fletched" and probably need to go up an inch or get a higher profile wing. Those Bloodrunners aren't long enough to really throw off FOC so it would have been highly doubtful if it was that.

Now speaking of fletch (and why does friggin spell check underline fletch?) that could also very well be the issue. He may very well not have enough angle on them. Some people try to get away with a little 1.5 to 2 degree offset (basically straight) on their fletching and that just will not cut it for most fixed blade set up's. It's fine and dandy for a field tip but not so good for a fixed.

Topgun 3006

(and why does friggin spell check underline fletch?)

It underlined it because you improperly used the word as a noun. Fletching would be the proper terminology in that sentence and you would use the word fletch strictly as a verb when you would say you are going to fletch your arrows. I also believe what you stated in your response about BH flight is accurate, although I'm a novice in archery compared to your many years of experience.

super_hunt54

I've heard several people nowadays trying to say that "steering" is a myth and that properly aligning your Broad Heads to your fletching is not needed. I find it funny when they try to "tote the company line". Most of today's advancements in BH technology is to fight planing. Better aerodynamics with less of a cross section to react to cross wind. In a few of these, that has resulted in much more stability off the string. Less need to align to your fletching. But with many of them you STILL need to align properly or you will end up with poor down range flight. It's simple aerodynamics. You have the blades trying to fly the arrow and the fletching trying to fly the arrow. If not properly aligned, they fight each other and arrow stability is lost. How that has obtained "myth" status I have no idea. It's more along the lines of simple observation. Advanced physics isn't needed to understand the concept yet many out there listen to what the advertisers are trying to shove down their throats to make them believe they have the best flying BH in the world.