HOW SHARP IS SHARP ENOUGH?

[OLDSALT]

#5508

I HAVE READ AND HEARD A LOT OF INFORMATION CONCERNING THE SHARPENING OF BROADHEADS BUT I HAVE NOT FOUND OUT JUST EXACTLY HOW SHARP THEY SHOULD BE. I HAVE WATCHED SERVERAL FRED BEAR VIDIOS AND SAW HIM TAKE A FEW SWIPES AT HIS BEAR RAZORHEADS WITH A FILE AND THAN DECLARE THEY WERE GOOD AND SHARP. SOME PEOPLE USE A STONE HONE[course and fine] AND PUT SUCH AN EDGE ON THIER BROADHEADS THAT THEY COULD SHAVE THIER BEARD WITH ONE. I HAVE A VERY DIFFICULT TIME GETTING THAT KIND OF EDGE ON THEM BUT DO I REALLY NEED THEM THAT SHARP TO KILL A DEER WITH?

[Hiram]

#41717

There is a thread which goes into detail on this subject already existing here. You might try a search on broadhead sharpness or sharpening broad heads. I personally strive for shaving sharp on my hunting heads.One way to test them is with the rubber band method if you are afraid of cutting yourself trying see if they shave. You simply stretch several rubber bands across a small box fairly tight, on opposing sides so the broad head will two separate surfaces to cut. Push the head through and see if it cuts with ease. I simply just try the shave test on my arm but do not recomend it unless you are well versed in the practice. Another way is to drag the sharpend surface across a thumbnail for resistance. Another way is to test cut it on a piece of notebook paper held on the upper corner.

[tom-wisconsin]

#41961

In the Ashby library section the Doc has an article entitled “Getting an Edge on Success”.

[Clay Hayes]

#42586

OLDSALT wrote: I HAVE WATCHED SERVERAL FRED BEAR VIDIOS AND SAW HIM TAKE A FEW SWIPES AT HIS BEAR RAZORHEADS WITH A FILE AND THAN DECLARE THEY WERE GOOD AND SHARP.

I can get a broadhead shaving sharp with just a file. The trick is to raise a bur then cut it off.

And, no, you don’t need them that sharp to kill a deer. You need them that sharp to kill a deer quickly. 😉

If you have trouble sharpening a particular type of head, try another. I can’t sharpen a 4 blade very well, and a grizzly is harder for me to sharpen than a magnus or zwickey, but it can still be done. It just takes a little more time.

The broadhead is what does the killing. Don’t slouch in this most important, yet often neglected, area.

ch

[Robin Conrads]

#42917

Hiram wrote: There is a thread which goes into detail on this subject already existing here.

Daniel covered this pretty well in his thread called The anatomy of a broadhead’s edge.

[Cottonwood]

#53770

I wish his pictures were still up, so we could see them.

I still have my stone from when I used the G5 Montec’s with the other un-named bow. The one thing we did when using it, is to take a black felt pen to mark your blade edge on both sides (3 blade BH) then use your stone, and then a leather belt over the edge, just like you used to see the barbers use on a straight edge razor.

But a 6″ x 6″ piece of wood with a hole cut in it, with rubber bands stretched across is a what we teach in Bowhunters Education, and much safer than the shave test or using your finger nail, as most of our students are 12 to 18 yr olds with few adults. But even a juice can, soup can with both ends cut out will work as well, then stretch you the rubber bands in a crisscross pattern.

I guess there are several ways to do this, but this is one I use.

[Robin Conrads]

#53799

Dang. I didn’t know the photos were gone. They really added a lot to the explanation. 😥

[David Petersen]

#53806

It’s so strange that some of our most informed and vital members, like Daniel, Doc Ashby, Kingwouldbe and Sharpster for examples, are either here every day in full force, or else disappear entirely for months at a time. Ed is plagued with serious medical problems, while Daniel (I hear) is massively busy in his profession, as is Sharpster/Ron Swartz. Still, it sure would be nice if these and other experts in their fields could check in with us monthly or so, as does Fletcher. I miss ’em. :?:(

[Fletcher]

#54345

OLDSALT wrote: DO I REALLY NEED THEM THAT SHARP TO KILL A DEER WITH?

In reality, no. Pretty sharp will kill, but it’s not nearly as effective as a really sharp edge. The sharp edge will kill much quicker and leaves a better blood trail. It takes only a little more effort to get that very sharp edge and it is well worth the effort.

The very sharp edge isn’t hard to achieve. It only takes some technique and practice. If you seem to be “sharpening challenged”, get yourself some sort of tool, like a KME, and learn to use it. There are YouTube videos and tutorials on some of the other sites like TradGang. If all else fails, ask your buddy how he does it.

[J-dog]

#54724

I want to be scared when handling mine!, I can get em prety dang sharp with a stone but since I started using the paper wheels from ABS – there is no going back. Still keep my file on me in the field, just in case; but then where I hunt I carry three arrows and am highly unlikely to have to resharpen before hitting the house again. Those paper wheels will truly make an edge that will frighten you in 2 minutes or less.
Sharpen them all grizzlys, STOS, that I normally use and then wrap em in duct tape so as not to beat up my edge till they go on the end of an arrow. IDEA: might carry a couple spares wrapped in DTape in the pack?

[Mark Turton]

#54933

I find sharpening a form of meditation if I don’t clear my mind and focus on the job in hand I will pay, in blood.

If you are laying aside sharpened blades dip them in the wax toolmakers use to protect cutting tools, stops corrosion and protects them from minor damage.

Mark.
PS. I also miss Daniels input.

[LimbLover]

#59908

I got mine to hair popping last year with a little bit of force but not shaving like a razor blade.

This year I’m taking mine to my Dad’s neighbor who has been doing it for 30 years. His heads are always razor sharp.

I’ve watched the videos but I’m still not getting it. I’m going to have him show me ropes.

[sharpster]

#15503

David Petersen wrote: It’s so strange that some of our most informed and vital members, like Daniel, Doc Ashby, Kingwouldbe and Sharpster for examples, are either here every day in full force, or else disappear entirely for months at a time. Ed is plagued with serious medical problems, while Daniel (I hear) is massively busy in his profession, as is Sharpster/Ron Swartz. Still, it sure would be nice if these and other experts in their fields could check in with us monthly or so, as does Fletcher. I miss ’em. :?:(

My apologies Dave, Robin and to all. Yup, guilty as charged.

Now to see if I can add anything even remotely useful…

“How sharp does a broadhead need to be to kill”? That’s easy- not sharp at all. Any animal can be killed with a target point if it punctures both lungs (bi-lateral pneumothrax). The reason a broadheads level of sharpness is so critical is not so much to up the odds of a kill (although it certainly does). The level of sharpness plays a huge part in upping the odds of our actually recovering that animal. (and that’s the real goal, right)?

There are many benefits and no downside to getting the absolute sharpest edge we can on our heads. As the level of sharpness goes up, the level of drag/resistance on the head from slicing soft tissue goes down, result… increased penetration. Translation- A crazy sharp BH requires and uses far less energy to penetrate hide, hair and soft tissue than a semi-sharp head of the same design/weight does. So a shaft with a super sharp BH will have used up considerably less of its limited energy when the BH reaches the off side of the animal and will have a much greater likelihood of continuing through and attaining a full pass-through than a shaft with a pretty sharp head will, even when bone is encountered.

The biggest benefit of a surgically sharp broadhead is in its ability to dramatically up the odds of a successful recovery of the animal. This is accomplished in two ways. Foremost is the impact on the bloodtrail. All else being equal, the best bloodtrail will always be produced by the sharpest broadhead. Not the biggest BH or the one with the most blades but the sharpest BH. Few things in bowhunting are set in stone but in my mind at least, this comes close.

Another often overlooked and very under-discussed benefit of blazing sharp broadheads (particularly 2 blade) is the amount of flight response triggered in the animal at the shot. In other words, the animals reaction to being shot. If we can zip an arrow right through an animal in a flash, (without hitting heavy bone) often they’ll jump and look around like “what the heck was that” and not even realize that they’re injured. This is exactly what we want because an animal that doesn’t know it’s been shot frequently doesn’t run. They just casually walk away with blood pouring out both sides and fall over in sight. I used to think the best bloodtrail was the one a blind man could follow but I’ve changed my mind, the best bloodtrail is without question, the shortest bloodtrail.

When heavy bone is hit, that animal instantly knows that something very bad just happened and he’s headed for the next county at hyperspeed. Even with a perfect double lung hit it can take 90 seconds or more for the animal to succumb, and we all know how much ground they can cover in that short time. In this case the level of sharpness becomes even more critical because we’re not hounds, and we can’t scent track. The only hope we have of recovering the animal is to follow the bloodtrail, and the sharper the head, the more blood there will be on the ground.

I’ll be the first to admit that a super sharp BHD will never make up for poor shot placement. The complete recipe for consistant game recovery is: 1) Shot Placement
2) Penetration, and 3) BHD sharpness… and we need all three ingredients.

Ron

[David Petersen]

#15549

Ron — Your “flight response” tip is critically important, and I recall discussions of it many years ago, then it just sort of disappeared, including from my mind. So important! Aside from sharpness, and as you suggest in parentheses, it seems logical that the more blades and the wider the broadhead, the more shock will be delivered on impact and the animal thus alerted to flight. Which brings us back to Ashby’s Mechanical Efficiency (ME)recommendations — long, narrow two-blade. That said, I can’t wait to try out the huge new El Grande 200s. Huge as they are, they still have near optimal ME. It’s all fun. dave

[Patrick]

#15826

Awesome, thought provoking post Ron!

[tom-wisconsin]

#16001

Thanks Ron et al. Always learn something here.:)

[MontanaFord]

#16646

Ron,

Thanks for dropping in and giving us some food for thought.

Michael.

[Dan Jackowiak]

#17221

I had completely forgot about the 3 blade and the flight response as well. It is a fact tho, at least from my experience 20 yrs or so ago. Back then I killed quite a few deer with 3 blade heads shot from compounds and all of them took off like rockets, generally going as far as they could before they died. When I went to traditional I went to 2 blade heads and observed the first few kills, most deer would run maybe 20 yds then walk until they fell over. Elk would spook a little with a pass threw from the arrow making noise in the brush on the other side. Then they would either walk off or just look around a little bit before falling over.

Those heads I used back then were the chisel tip variety, but it would only make sense that the great area of a coc 3 blade would cause the same response. But I’m not sure about that cause I’ve never tried it? Would make for a good experiment and hopefully I get a chance to find out this yr.

[kingwouldbee]

#21310

Um, I like-um sharp, thanks Ron, well said.

[kingwouldbee]

#21336

oops

[Ed Ashby]

#50534

Sharpster has said it perfectly. An arrow need not be sharp at all to kill … when everything goes well. I was present (in camp) when one whitetail was killed with a field point, and have met and talked with a bowhunter who killed a moose with a metal blunt. That’s not surprising. Non-expanding (solid) bullets are widely used on big game (such as buffalo and elephants) and are very lethal, even on body hits. Many humans have been killed with ice picks (for those of us old enough to remember what an ice pick is).

That said, there’s no such thing as overkill with an arrow and no such thing as a broadhead that’s ‘too sharp’. Just as with everything else in the setup of a hunting arrow it’s the marginal hit where maximizing the overall lethality potential of your setup will make the greatest difference. Also, as Sharpster pointed out, the sharper the broadhead you use the less reaction one generally sees when an animal is hit (excluding when a heavy bone is impacted). Ever cut yourself with an edge so sharp you didn’t even know you were cut until you saw blood? Most have experienced that at one time or another.

The thinner and sharper your broadhead, the smoother the cut and the less disruption there is to the tissues severed. The more ‘perfect’ the cut the faster the blood flow from the incision and the longer the clotting time before bleeding slows and/or stops (see the ‘hemmoraging cascade’ in “Getting and Edge on Success” for a more complete explination).

Ed

[David Petersen]

#52137

Watch for a pair of excellent articles by Doc Ed and Sharpster in an upcoming issue of TBM, covering why sharpness is important and how to attain it. Thanks Ed and Ron. 😉 dave

[Steertalker]

#52154

I used to think the best bloodtrail was the one a blind man could follow but I’ve changed my mind, the best bloodtrail is without question, the shortest bloodtrail.

AMEN!!!!!!!!

My personal experience with “crazy” sharp Grizzlies is that the animal goes down before a bloodtrail even starts:wink:

Brett

[John Carter]

#59651

Ron,your comments on flight reaction mirror my own thoughs on the subject.

My most resent Deer actualy ran 10 yards “then stopped turned around an came back to see what the heck had happened,,,an then fell over a few yards from where she’d been hit.
I wish I’d been able to film that for no other reason than to show guys that use those poke an cut things what can happen if you don’t “hurt” the animal.

Thanks,
John.

[sharpster]

#59815

That’s the way to do it John, Good for you buddy. I was talking with a compound shooter who lurks here but doesn’t post. He shoots 650+ gr arrows tipped with Grizzlies or Abowyers so he’s not your typical wheelie bow guy. He also uses decoys from time to time and has killed several deer that never ran anywhere. He says it apears that they think the decoy may have done something to them because after the shot the deer will walk straight over to the decoy and fall over. You may not have your kill on video but tell everyone you can about it. Congratulations! Thanks,

Ron

[Ed Ashby]

#60145

Just to add another important factor about ‘how sharp is sharp enough’, not only does your broadhead need to be “truly sharp” when it impacts an animal, it should be just as sharp AFTER it’s penetrated through the animal. If it’s not just as sharp at exit as it was upon entry then the broadhead has lost some of its cutting efficiency at some point during the course of penetration through the tissue(s). This retained sharpness makes the most difference (in recovery rate) on shots through tissue(s) that have few, or fewer, sizable blood vessels, such as stomach, intestival and pure muscle hits.

This is a sharpness factor that I see few bowhunters paying enough attention too, and one that does affect the likelyhood of recovering game on many less-than-perfect hits. Sharpenss retention requires good quality steel in the broadhead, which generally also means a broadhead that takes greater effort to get ‘truly sharp’ in the first place.

Ed

[RedTape]

#60575

Dr. Ed Ashby wrote: Just to add another important factor about ‘how sharp is sharp enough’, not only does your broadhead need to be “truly sharp” when it impacts an animal, it should be just as sharp AFTER it’s penetrated through the animal. If it’s not just as sharp at exit as it was upon entry then the broadhead has lost some of its cutting efficiency at some point during the course of penetration through the tissue(s). This retained sharpness makes the most difference (in recovery rate) on shots through tissue(s) that have few, or fewer, sizable blood vessels, such as stomach, intestival and pure muscle hits.

This is a sharpness factor that I see few bowhunters paying enough attention too, and one that does affect the likelyhood of recovering game on many less-than-perfect hits. Sharpenss retention requires good quality steel in the broadhead, which generally also means a broadhead that takes greater effort to get ‘truly sharp’ in the first place.

Ed

Can you get a blade too sharp, i.e. fine, resulting in a rolled edge when impacting bone and therefore a lack of sharpness retention? Or would that be caused by using the wrong bevel angle?

In the simplest of thinking , a finer blade would result in a sharper blade, however it would also make the blade weaker. Of course that’s not factoring in any other variable such as blade material, etc.

[Ed Zachary]

#60716

This has to be the best, most crucial and important topic/post/thread/discussion I’ve ever seen to date on TradBow. Kudos to Dr. Ed and all the other “heavies” out there!

Super sharp that stays super sharp = dinner 😀

Good hunting

[sharpster]

#61019

RedTape wrote:

Can you get a blade too sharp, i.e. fine, resulting in a rolled edge when impacting bone and therefore a lack of sharpness retention? Or would that be caused by using the wrong bevel angle?

In the simplest of thinking , a finer blade would result in a sharper blade, however it would also make the blade weaker. Of course that’s not factoring in any other variable such as blade material, etc.

Redtape,

I have a saying… Sometimes you can get a knife too sharp for a particular application but, a broadhead can never be sharp enough.

And you nailed it BTW, it’s about combining the right steel with a “take the hair off your arm in clumps” level of sharpness and using a bevel geometry that will support that cutting edge throughout the penetration cycle. I’ve heard it said soooo many times- “well a broadhead only needs to make one cut”. Yes, that’s true but think about the stresses that the cutting edge has to endure when making that one cut. A broadhead slamming into hair, hide, flesh, bone and even soft tissue at 160 fps with all the momentum and KE of a heavy shaft driving it through the animal in the blink of an eye is similar to a knife making 1000 cuts. I’ll let Ed explain what he means by “thinnest edge” but I know he’s not talking about extremely low sharpening angles.

Ron

[Ed Ashby]

#61145

How low a sharpening angle you can use on a broadhead and still have it retain its sharpness all the way through the course of penetration is a function of the quality and hardness of the steel in the broadhead.

As Sharpster aludes to, an edge can, in theory, be reduced to a single molicule of steel at virtually any sharpening angle, but I also prefer as long a bevel (as low a sharpening angle) as I can use and still have the edge retain its sharpness during penetration.

The edge bevel itself is a simple machine; and inclined plane. The lower the sharpening angle the higher the mechanical advantage (MA) of the edge bevel. The higher the edge bevel’s MA the deeper it slices at any given level of pressure between the edge and the tissues; or one could say it slices equally deep at less tissue pressure than an equally sharp edge having a lower mechanical advantage.

When the broadhead you are using has softer steel you need to have the angle of the edge bevel more abrupt (a steeper sharpening angle) in order to prevent the edge rolling or dulling during the cut, but that sacrifices the edge’s MA.

To put it in simple terms, when an edge bevel with a higher MA barely touches the wall of a vessel it is more likely to cut into the vessel than is an equally sharp edge having a lower MA.

Attention to small details sometimes makes a big difference in outcome. This tiny difference in the broadhead’s edge design can make a big difference on marginal hits.

All that not withstanding, you need to find the correct sharpening angle for the individual broadhead you are using, and that’s why you need to evaluate just how sharp your broadhead is AFTER EACH SHOT you make through the tissues of game. We learn from observing the outcomes.

One more point. While the “ideal edge” will remain totally undamaged and retain its sharpness on each and every shot through tissues; regardless of the tissues hit; it’s FAR better to have a broadhead with steel hard enough that it loses a few small chips from the edge on hard tissue hits than it is to have one with steel so soft the edge dulls, rolls, or, even worse, bends on hard tissue impact.

Ed

[David Petersen]

#61250

Ed and Ron — speaking of chipping of edges in hard steel, I recently noticed that one of my ABS Ashby heads, probably the one I shot through a bull elk shoulder last year for penetration testing (19″ with an angled shot from 15′, via the scapula flat). I’m thinking that head is 57, which would make it the hardest steel on the broadhead market (though I may disremember), but it’s solid cast and thick. These chips are few and so very tiny as to not be a concern. But I’m rather surprised. Grizzly is about the same hardness, I believe, and thinner, yet I’ve never had one chip. Maybe you can update us on relative hardness of leading single-bevel heads? So far the Brown Bear — around 53 Rockwell? — seems the perfect combo of hardness, thickness, factory sharpness and sharpenability, with a nice price to boot. Even so I’m elking this year with the new El Grande. dave p

[wildschwein]

#61275

Ok I think I am following you guys so far. But I have one more question. What is the ideal level of Rockwell? And is there any source stating where various broadheads stand in comparision? I will probably be shooting Ace Standards 125grs at big game this year but cannot find what Rockwell their steel is. I doubt anything will keep me from using them this year, but it would be interesting to compare them to other heads.

[Ed Ashby]

#61282

Dave, the Grizzly’s I’ve had hardness tested have run from R52 to R56, with R52-53 being the most common hardness. The ABS Ashby is harder, and that’s definitely noticable when the retained sharpness is tested after penetrating both the on and off side ribs of a buffalo.

Specifications on the ABS Ashby calls for R58 hardness. That not withstanding, the folks at ABS have recently changed the company doing the heat treating on the Ashby BH because they were getting a few heads testing above R62. I’ve tested up to R62, and that was the point where I first started to commonly see small edge chips (which is why the ‘spec’ was set at R58). Above R62 hardness would likely increase the number of chipped edges significantly.

BTW, the ABS Ashby is not a cast head. Each head is individually machined from a solid block of steel.

Ed

[Ed Ashby]

#61288

Wildschwein wrote: What is the ideal level of Rockwell?

The ‘ideal’ hardness varies by the individual type of steel used. Regardless of steel type, I’ve not found any broadhead with a hardness much below R50 that (when ‘truly sharp’ to start with) routinely retains its edge sharpness after penetrating a large animal, even when sharpened at higher sharpening angles.

I think this is why the (relatively) rough, ragged file sharpened edge became popular. When the edge is not actually sharp a ragged edge is more likely to tear the tissues, rather than push them aside. The ragged edge is better than a dull edge, but it is far inferior to a truly sharp edge that retains its sharpness. A small detail that shows a big difference in results.

Most broadhead that are EASILY file sharpened will have a hardness no greater than in the upper 40’s.

Ed

[RedTape]

#62040

sharpster wrote:

Redtape,

I have a saying… Sometimes you can get a knife too sharp for a particular application but, a broadhead can never be sharp enough.

Ron

Thanks for the info. I’ve always got my broadheads sharp enough to cut hair…but never quite to what I would consider a *razor* blade. This was partly because of the softness of the broadhead. I’m switching to Grizzlys this year and will plan on stropping them until they are properly sharpened.

[Ed Ashby]

#62214

sharpster wrote: Sometimes you can get a knife too sharp for a particular application

The perfect example of a knife ‘too sharp for the job’ is one used for fleshing a hide. The best edge for that job is one that’s a bit ragged and far less than razor sharp. Too sharp and it’s almost a certainty that you will end up cutting through the hide too.

Ed

[Fletcher]

#62824

Wildschwein, you can go afield with full confidence in your Ace heads. I don’t know what their Rockwell is, but mine have always held their edge all the way thru. I sharpen my double bevel edges to a total 45 degree angle; 22.5 on either side.

[jaytbuzzard]

#62866

I sat up late last night sharpening my Bear Razorheads. The hair just pops off of the arm. This will be my first season hunting deer. I’ll be using my Dad’s Black Widow recurve and his Bear Razorheads, he passed away a few years ago. I can’t wait.

[Ed Ashby]

#63266

jaytbuzzard wrote: I’ll be using my Dad’s Black Widow recurve and his Bear Razorheads, he passed away a few years ago. I can’t wait.

Situations like this are one of the intangable factors that make a hunt something truly special. Hope you nail a monster buck!

Ed

[David Petersen]

#63289

Thanks, Ed. Inexplicably, for some reason I “want” the El Grande to be the all-around best head; I just really like its looks I guess. Yet all things considered including last year’s elk, I keep coming back to the believe that at the moment, with all Ashby info considered, the Brown Bear is the best head on the market for the money. Yet I’m packing two 200 El Grandes (one of carbon with EFoC, one on a heavier wood shaft with nornal FoC) and an ABS Ashby, as these have been tested (by me) only on freshly killed elk and I want to see performance on a live moving animal. Now to find a cooperative bull! 😀 dave p

[Ed Ashby]

#63309

Go get ‘um Dave! What I find so great now is that we (finally)have enough well designed, quality single-bevel broadheads around that it’s getting harder and harder to chose which one is best. That’s a very good ‘problem’ to have!

Ed

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