Quote:
Originally Posted by Outbakbowhunter
Woody,
I beg to differ, a double bevel broadhead with 20 degree bevel angles on each side of the blade, has a combined angle of 40 degress. ( 20 X 2 = 40 ) and we all consider that a good angle for sharp.
A single bevel angle is what it is. What ever the broadhead maker sets it to be.
I believe that single bevel edges are plenty strong enough, as long as they are made at no less an angle than 30 degrees angle of bevel.
Which is still significantly sharper than your example of the 20 degree double bevel. (20 X 2 = 40 degrees )
I also disagree about the twisting cutting motion that single bevel edges give.
If they dont twist, as you say, how is it that all the photo's of s shaped entry wound pictures, of single bevel heads, are shown on bowhunting forums, when ever the single bevel broadhead style is discussed.
Either you are mistaken on that point, there is another explanation for them, or there are one hell of a lot of photo shopped photos circulating out their with a pro single bevel broadhead agenda.
I mentioned in an earlier post, that I dont think a single bevel makes all that much difference on deer sized game, double bevel heads are still working just as good as they always did, so dont misunderstand me, I am not advocating single bevels to the exclusion of all others.
I personally like them because I find them very easy to sharpen, and I do think they have a very small edge in accuracy ( tighter groups ) especially as the range get out to 50 yards or more.
I have had quite a few guys say this to me, its not just my single idea, but when I can afford one I would really like to buy a hooter shooter to ascertain whether or not its just my misguided opinion or a prove-able fact.
It is true that most commercial single bevel style heads in the US, are made with very low angles, which can work if the blades thickness is enough to allow higher tempered hardness values for edge retention.
I think this works on the 200 + grain heads if you are going on a safari in Africa, but in the 125 grain weight class broadhead for average day to day hunting, a 30 degree bevel angle on 1055 spring steel blades, about 50 Rockwell hardness is about right.
Ultimately, the commercial success of any particular broadhead style, over the long term, depends on whether it works.
If a thing is a lemon you will only get one purchase per customer, they return for more only if they are happy with its performance.
Whether or not they are your "cup of tea" I do think single bevels are here to stay.......
|
Angle isn't the only thing that contributes to sharpness. Most single bevels are at a lesser angle than 30 degrees and suffer a greater loss of edge retention just as I wrote in the begining and in the article. I just reported that from what I actually saw while testing on carcasses from NC whitetails to AK moose. I also observed the inconsistency of the rotation through carcasses by use of a high speed video camera. They will turn counter to their suggested rotation as deemed by the bevel. I will be putting that video up on my website eventually along with microscope pictures of damage to the edge in comparision to a double going through the same area of a carcass.
From what I see first hand, the tip has more influence than the bevel on the blade but the larger you make the tip the less efficient it is. The more it will increase directions on impact, push bone and stretch hide, exhausting energy. I personally don't see the need for such large tips on any NA game or SA for that matter, its more eficient to strengthen by blade thickness for volume than geometry. Since most use heavier heads for such game it is more suitable.
Like what you like, doesn't really matter to me. I don't see the benefit as claimed to the single bevel or the need to re-invent the wheel. If the benefit was as obvious as some claim we would use it. Its definately easier to manufacture and would speed up run times on grinding heads, which equals more money but the benefits of the double bevel outweigh it on our line.
I believe the majority of the "S" wounds you see in hide are from the tip extending hide beyond its limits, rupturing it or trying to force its way through and wrapping it up. The rotation isn't consistent in wound tract survey's.