Something to Ponder
 

I did some rough calculating involving heavy arrows flung from a 29" DL Allegience pulling 70#s, and came up with a mind boggling numbers. Having fallen into this trap before and being fooled since many high performance cams don't seem to be as efficient at heavier arrow weights, I emailed Pat to see what the AMO is.

Pat told me they don't AMO their bows, but he did fling some different weighted arrows through the chrony and gave me the results. Doing some quick extrapolating from his tests to my desired set up, ponder this-

A 70# allegiance drawn 29" should fling a 550 grain arrow approximately 275 fps, for a whalloping 92 foot #s of KE, and momentum out the ying yang.

Easy to tune, easy to draw and hits like a mack fricking truck... Mercy.

RE: Something to Ponder
 

Thats with the hush kit and nock set:)

RE: Something to Ponder
 

I'm pondering ?????? :D

But how can you get 275 fps out of a bow that IBO's 328 max after it's dropped an inch in draw length , set up with a hush kit, and shooting an arrow 200 grains over ! That has to be the most efficient cam system ever .........and maybe it is ! I will definately go test one when it comes in ! ;)

RE: Something to Ponder
 

I can't see those numbers coming to fruition. The allegiance has roughly the same IBO as my SC Patriot and I am shooting a 30" draw and a 444 gr. arrow about 287 fps with a bare string. Not that that is anything to sneeze at by any means. But if you added another 106 grains of arrow weight that would account for a minimum of 30 fps speed loss and that is with an inch more draw length. So, I just don't see how those numbers are going to work out. If you make it an 80 lb bow and added an inch of draw length that would appear to be closer based on the specs provided, unless I have missed something.

RE: Something to Ponder
 

i agree with silentassassin, 275fps is a hefty number for that set-up. i would love to see actual numbers though...

RE: Something to Ponder
 

Rangeball,
I'm assuming you are figuring your calculations from these numbers.........(with hush kit of course;))
Ponder these numbers.......these are the actual test numbers for a 28"/61# Allegiance

28"/61# (measured) shot a 536gr 2117 at 237fps. (67ft lbs of KE!) From a 28"/60# bow with a 7" brace height.
Think about those numbers for a minute.[:-]

That's 28"/61#.

It seems like this cam system is EXTREMELY efficient with heavy arrows.

That same bow shot a 301gr arrow 306fps (62ft lbs of KE) and a 398gr arrow 272fps......that's losing 1fps for every 2.85 grs added.

Now take that same 301gr arrow and factor in the 536gr arrow at 237fps. That's a loss of only 69fps for an addition of 235grs of arrow weight on a 28" draw length bow! The efficiency increases to 1fps lost for every 3.4grs added.

RE: Something to Ponder
 

Matt, that seems like them :)

Ok, I just realized I figured for a 30" draw, not 29". At 29" it should do 265ish, for just under 86#s of KE... Probably still more than adequate.

But for you fellers with arms... Mercy... :)

RE: Something to Ponder
 

I'm going to go out on a limb here, and say that they are going to sell a few of these things this year.[:-]
And oh yeah........it draws smooth!

I'm almost giddy thinking about these bows. (Me and my 30" draw length:))

I was intending to shoot a 30" / 70# Allegiance for the 2005 hunting season. Anyone make a 4" cutting diameter mechanical head?;)

RE: Something to Ponder
 

hi guys i just wanna add i was inches from buying a mathews and then i read some posts on here about bowtechs..i never held one in my hand b4 and found a brand new one on e-bay(mighty mite) and i absolutly love it.
i am shooting 27.5' ics 400's 390 grain... 28" draw ...70#'s and i'm getting 295 w/ hush kit..........recently i removed the silencers from the string and installed string leeches and gained 3 fps.oh yea peep and string loop.
whisker biscuit rest

just my 2 cents


otto

RE: Something to Ponder
 

Hey Matt... If they have these available in a 31" draw so I dont have to "short draw" my 30" Liberty, I'm sold!

2005 Allegiance at 70 lbs + 31"+ 560 grain arrows = enough penetration to go through a Buick!

RE: Something to Ponder
 

Josh,
Unfortunately no the Allegiance only comes in a 30" top end..........BUT the Old Glory DOES come in a 31" draw length.

It's 37 1/4" ATA Vs the 33 5/8" so really it's only a little over 1" ATA longer on either end, and a bit larger brace height at 7 1/4".......IBO speeds are just a tad behind the Allegiance at 315-323. That might be the bow for you if you want to kill tanks, or buildings, or entire hillsides or something?
[:-]

RE: Something to Ponder
 

Old Glory, that's the plan right now. I was getting about 285fps w/ some 415gr X-Cutters with 135gr's upfront for ASA (that produced 75lbs/ft KE), and over 290fps w/ my ACC 3-49 from what I was calculating in TAP. DL = 30" DW = 60lbs

I'm really thinking about shooting the Rocket Hammerhead next year with that set-up.

RE: Something to Ponder
 

That's exactly what I had behind my target as a back stop, just in case it blew through my block target...;):D

RE: Something to Ponder
 

ROFLMAO "That might be the bow for you if you want to kill tanks, or buildings, or entire hillsides or something?" Matt / PA , that was GREAT! LOL !!

Just thought that was darn funny. I needed a good laugh.[8D]

RE: Something to Ponder
 

Do you fellas want to take a guess what Big Daddy has on order for his first Bowtech bow of the season? :):D

What kind of numbers do you think I will get out of an Old Glory at a 31 inch draw length with a 70 lb draw weight flinging 440 grain Bemans? :D I haven't figured it out yet but I bet my backstop is going to be crying....Buick or not. ;)

RE: Something to Ponder
 

309fps for a tad over 93#s of KE...

I think I just saw your target run screaming over a hill into the sunset... :D

So, what head you gonna shoot?

RE: Something to Ponder
 

Can you screw two Hammerheads on the front of an arrow?

That might keep his arrow from blowing thru. :D:D

RE: Something to Ponder
 

Hmmm... I wonder if you could unscrew a pathfinder tip and screw in another head, offset from the others so you'd have 6-8 blades cutting a 2-3" hole...

RE: Something to Ponder
 

Dang-it, Range! You just had to do that, didn't you? You've done gone & got me pondering now. But I've already bought an '05 bow. You're going to have to explain to my wife why it is that I'll need to get another.

I picked up a Liberty about this time last year & have been very pleased with it and I've been able to resist the excitement surrounding the '05 Bowtechs until now.

I always knew you were trouble.:)

RE: Something to Ponder
 

Go with your gut. It's usually right... :)

That said, your gut told you you were gonna have to have one of these as soon as you heard about them, didn't it... If you need a note for your wife, just say the word :)

RE: Something to Ponder
 

Hmmm, I haven't given broadhead choice much thought until now. I was just going to go with the usual 2 inch Hammerheads but with that much KE I might look for something bigger.

Do they make something bigger?

:eek:;)

RE: Something to Ponder
 

This just doesn't seem possible to me for some reason. If you get 275 with that arrow weight I would suscept that the 29 inch draw length is not really 29 inches AMO. I would have to see it and measure it myself to believe it..

good luck at any rate. I'll bet it would be quiet though.

RE: Something to Ponder
 

Bees, we're both right :)

I corrected myself a few posts back. I had mistakenly figured based on a 30" draw. 29" draw does 265ish with just under 86#s of KE... ;)

RE: Something to Ponder
 

Oh I suppose I should read all the posts before I replay. But that is still fast for that arrow weight. I imagine you are drawing 70lbs or what ever max is for a long time. to aggressive for me, shoulders wouldn't take it, what is the brace height on that thing?

RE: Something to Ponder
 

I believe 7", with the bulk of the peak draw in the front 1/3 of the draw cycle, when most seem to be the strongest since using their larger muscle groups.

RE: Something to Ponder
 

I still don't see that happening at 60 lbs pull. At 70 lbs and 30 inch draw if you had a bow that would shoot at the top end of the listed specs (328) and you use the 3.4 number that Matt provided that would still put you at a loss of 59 fps for a top speed of 269 fps with a 70 lb bow. That is IF it is at the top end of the specs and IF the 3.4 number holds up. So I just don't see a 60 lb bow pulling that off. Not trying to rain on anyones parade I just don't want people to be disappointed when the bows get here and they don't live up to expectations that may have been set a little to high.

PS with my numbers it comes out to 88 lbs of KE with a 70 lb bow which is still pretty awesome.

RE: Something to Ponder
 

MAT/PA ,Buckblasters should do the trick for you , 6 blades and I think over 3" cut , Should feild dress them at the point of impact :)

RE: Something to Ponder
 

Me either. That's why I said 70# in my first post... :)

RE: Something to Ponder
 

Ahh...I got off on the wrong track thinking you were talking about a 60 lb bow. But the inch less draw puts in in the same boat basically IMO. I still don't think it's going to make it into the 260's with the average Allegiance. An exceptional one may barely crack the 260 mark at the specs you listed but it will be the exception and not the rule.

RE: Something to Ponder
 

You're quite possibly right, but remember this is with the nock and hush kit. Some tweaking could be done if one desired. Either way, it seems to be packing a whallop with heavier arrows, while still providing blistering speeds with lighter arrows, not a combo I'm used to seeing.

Time will tell, until then, we'll continue pondering... :)

RE: Something to Ponder
 

I see a little confusion in the numbers here.........
I'll see if I can add to it.

First off I don't even know if that 3.4grs for every 1fps loss will hold true for a 70# or a higher draw length.........remember we were using a 28/61# bow for the example so the actual efficiency might vary. However if I were to guess HOW it would vary, I would guess that it will be even MORE effecient, based upon the bow being designed around a 30" platform.

Common sense would lead me to believe that if a bow at 28"/60# could do 237fps at 536gs, that if you took that same bow and added 2" of draw length to it, chances are you have a bow that is doing about 257fps +/- (if we all agree that 1" draw length generally means 10fps+/-) After all the starting point for the 28"/61# Allegiance was 306fps? 306fps is basically a 20fps drop over the IBO listed speed.

Now if you take that same bow that is doing (for sake of argument) 257fps at 30"/61# and a 536gr arrow, increase arrow weight by 14grains to 550(14gr/ 3.4= 4fps),......this should result in a net speed of about 253fps.
Now keep everything the same but bump the draw weight up 9-10#, and I find it very possible that a 30"/70# model could easily do 260+ with a 550gr arrow. After all the 30"/60# should only be about 6-8fps under 260fps.

I do have an “Armchair Engineer” theory WHY this thing is so efficient, and it has to do with the shape of that draw force curve.......it doesn't seem to slide up to a peak weight, it is basically at or near peak weight from the get-go (hence the comment that it “feels like a recurve”, and “it is stout right up front” ). This gives it more "front end drive" (for lack of a better term) which would be more necessary in powering a heavy arrow than a light one.
Where a regular bell shaped draw force curve actually loses weight/performance on the return cycle peaking somewhere toward the middle, this Equalizer cam carries it across almost to the point of rest givin’ this puppy one heck of a shove.

I didn't engineer the thing , but that is my impression of the nuts and bolts of why I think we are seeing some of these numbers with heavy arrows.
I am also starting to see in little snips of these reported numbers that this cam system probably isn't going to conform to our notions of "Standards" with respect to arrow weight/ velocity that we've grown accustomed to over the years.
This is a different animal that's for sure.

The thing I really find AMAZING in all of this is that I am hearing comments that it is as quiet as a Liberty and maybe just as recoil free.
Can you even imagine?

RE: Something to Ponder
 

Here what TAP is telling me. For arguments sake I'm using the top end number 323fps as well as 331fps (bare string +8fps).

@ 323fps
30" 60lbs 540gr = 250fps 75KE
30" 70lbs 540gr = 267fps 85KE

@331fps (bare string)
30" 60lbs 540gr = 256fps 79KE
30" 70lbs 540gr = 273fps 90KE

I have found TAP to be quite accurate w/in 1-3fps, take them for what they're worth. If you look at the low end. 315fps & 323fps (bare string).

@ 315fps
30" 60lbs 540gr = 244fps 71KE
30" 70lbs 540gr = 260fps 81KE

@ 323fps (bare string)
see above

I would say 260fps w/ 500gr+ arrow should be easily attainable in my opinion and if the cam is more efficient then these numbers could be higher.

These numbers are based on theoretics no actual testing will be done, hopefully next weekend I'll be doing some testing with my 30" 60lb Old Glory.

RE: Something to Ponder
 

My interpretation of the efficiency of the Equalizer cam: As with most cams, the weight builds as you draw. The E cams are near peak at the front. Other cams will hit hard, initially, at release. Then deliver less energy as the cam rotates toward brace. The E cam will not hit quite as hard initially, but will continue to deliver more energy, as it returns to brace. If I'm right, this would account for the higher efficiency with heavier arrows. Possibly with shorter draw lengths as well.

RE: Something to Ponder
 

The Old Glory I ordered will only be 50lb.limbs so I guess I will be checking out the lower end of the K.E. scale:D When they chrono the bow at the factory will it be at 5 grains/pound? I don't have any arrows less than 300 grains[8D]

RE: Something to Ponder
 

Bowshopper,
Yes they will chrono the bow with a 250gr arrow.....but it doesn't sound like you will have too many probelms with your 300gr ones.;)