IBO speed for a Black Hawk

[Mikelo]

Does anybody know the approx IBO speed for a 60" SR swift Black Hawk takedown recurve? I have been trying but it seems hard to find...

[ishoot4thrills]

Nobody I know of puts their trad bow through that much torture just to see what their trad bow shoots at 5 grains of arrow weight per pound of draw weight. I can't imagine shooting a 300 grain arrow out of a 60# recurve drawn to 30 inches!

That's best left to the wheelie bows.

Most trad shooters, that care about these things, check their bow speed with arrows at 8 or 9 grains per pound of bow weight at around 28" draw when comparing their bow with other bows.

[redant 60/65]

Not really Doug       There are alot of trad shooters that shoot less than 7grns per inch. I hunt with heavey arrows, and shoot a lot of 3-D with  lighter arrows. And I don't know the answer to the question about the Black Hawk bow speed.

[Mikelo]

Yeah, Larry, I myself shoot with exactly 7,01gn per inch, although I hunt with much heavier arrows...
It is just curiosity...

[ishoot4thrills]

But we're not talking 7 grains per pound here. IBO specs are 5 grains per pound!

And, btw, it's grains per pound instead of grains per inch.  

You were asking about IBO speeds so that means 5 grains arrow weight per pound of draw weight. Lot of difference between 5 gpp and 7 gpp.  

You shoot 5 gpp and you're asking for trouble!

[Swamp Yankee]

Both IBO and AMO speed "standards" seem to be written for compound bows only.  I don't see how they could be applied to a recurve or longbow with the 30" draw requirement.  If either organization were to expand their standards beyond compound bows they would have separate rules for non-compound bows that make sense; but they won't because that's not where the money is.  Hopefully one day the "traditional" bowyers will come together and agree on a set of real standards to measure things like speed and string lengths that make sense.

You can certainly shoot any traditional bow at 5 gr per pound at 30"; but who cares if you can only do that a few times before the bow blows up?

[bigbadjon]

Theres a lot of hooplah about not shooting arrows below 7 gpp. I know in the old days everybody shoot lighter arrows and hunted with them and I have some doubts about how detrimental it really is. Maybe some tournament shooters or bowyers will chime in shortly.

[Jeremy]

Originally posted by Swamp Yankee:
Hopefully one day the "traditional" bowyers will come together and agree on a set of real standards to measure things like speed and string lengths that make sense.

The AMO standards for bow and string length were set in place in Feb of '68.  Strings are properly measured under tension which negates differences in materials and strand count and the bow's length is defined as 3" longer than the string length needed to properly brace it.  Both of those make perfect sense, IMO.
AMO speed testing is done at 30" with 540gr arrow - 9 gpp

 

Both IBO and AMO speed "standards" seem to be written for compound bows only.  I don't see how they could be applied to a recurve or longbow with the 30" draw requirement.

My draw length, with a longbow, is a hair over 30"  :D

[Swamp Yankee]

Originally posted by Jeremy:
 

Originally posted by Swamp Yankee:
Hopefully one day the "traditional" bowyers will come together and agree on a set of real standards to measure things like speed and string lengths that make sense.

The AMO standards for bow and string length were set in place in Feb of '68.  Strings are properly measured under tension which negates differences in materials and strand count and the bow's length is defined as 3" longer than the string length needed to properly brace it.  Both of those make perfect sense, IMO.
AMO speed testing is done at 30" with 540gr arrow - 9 gpp

Agree, except very few bowyers actually comply with this standard.  In my opinion, life would be a lot simpler all around if a 58" string was a 58" string and bowyers simply wrote what length string their bow needed right on the riser.  AMO used to be 4" shorter, then 3" shorter; so the "standard" depends on when the bow was manufactured; and if the bowyer complied with the standar or not.  Most string makers and suppliers don't even bother with AMO anymore for that very reason.  Check out Three Rivers or Kustom King; you can't even order a string by AMO length unless it's one of their own bows.  The world has moved on; AMO and IBO have not.
   

Both IBO and AMO speed "standards" seem to be written for compound bows only.  I don't see how they could be applied to a recurve or longbow with the 30" draw requirement.

My draw length, with a longbow, is a hair over 30"    :D   [/b]

Yup, but most trad bows use the 28" draw length as a default "defacto" standard draw length.  Some shorter bows simply don't draw well at all beyond 28".  All I'm saying is the standard doesn't make sense because it really can't be applied to all trad bows.  30" makes sense for a compound because it's pretty much in the middle of the range with those machines.  A 30" draw is pretty much on the high end for target recurves, and very much on the high end for hunting recurves (due to shooting style, not equipment so much)

[oxnam]

I think they use that abnormally long draw length to squeak out every single fps possible.  Makes the bows look a little better on paper.

[Archer Fanatic]

A friend of mine here in Ohio makes custom bows and he will not stand behind any of his bows that an archer uses any arrow lower than 8 grains per pound.

[Mikelo]

So you think 285 could be an accurate figure...?

[Jeremy]

Originally posted by Swamp Yankee:
AMO used to be 4" shorter, then 3" shorter;

Nope.  AMO standards for string length were NEVER 4".  They have remained unchanged since 1968.  The confusion, then and now, is bowyers and string makers not going by the standard.  The standards were adopted for a reason.

If a bow is marked 64" AMO it should need a string that measures 61" under tension.  A 10 strand string out of dacron that measures 61" under tension will measure under 60" resting.  An overbuilt FF string measuring 61" under tension will measure right around 61" when resting.

I should be able to order 6 strings, all with different strand counts and out of different materials for my bow by just giving the AMO length of 64".  That was the whole idea behind adopting an industry wide standard.  Those 6 strings will all measure differently when resting, but they should all measure 61" under tension and after settling in.

I should also be able to put those 6 strings on any of my 64" AMO bows.

Bowyers not going by the AMO standards or, worse yet, not going by the standards and marking their bows "AMO" is a HUGE pet peeve of mine.  String makers not measuring or marking their strings properly is a very close second!  And the ones that send out a 61" string that wasn't pre-stretched so you have to twist it up like crazy...   :mad:  

Ok, end of rant.

The 30" standard draw length for speed testing is arbitrary and is just meant for comparison purposes.  

Most of the guys I've helped with setting up their wheel bows have a 28" draw as well  

[ishoot4thrills]

Jeremy, that was a GOOD rant with some good info.