pounds per inch

[blacktailchaser]

the main question is how many pound per inch does fiberglass gain or lose in draw.....now i know this is differant from bowyer to bowyer...my bear grizzly is 55 @28...but i draw 26"...i just dont know if its 2# or 3# an inch...thanks

[TIM B]

Not sure but you could pull it 26 with a fish scale and see.
Tim B

[Whiteoak63]

Assuming the brace height is around 8” and it really is 55# at 28”, it should be around 2.75# per inch.

[McDave]

Most commonly it’s between 2-3 lbs/inch, but it varies along the force draw curve for each bow. For a 55# bow at full draw that is not stacking, my guess would be 3#/inch.

[Appalachian Hillbilly]

My guess is around 3 as well. Heavier poundage bows build faster. My 50 kb is about 2.75, my 40 is less.

[blacktailchaser]

whiteoak63 brace is 8 1/4....McDave thanks i am think its 3'' thanks guys

[woodchucker]

"General rule of thumb" is about 2 1/2# per inch.....

However...  My experience has been, (with my old Bear recurves)
That over 28" is closer to 3# and under 28" is closer to 2# per inch. OMMV

[stevem]

Assuming a linear draw curve try this-  55# / (28" - 8.25") = 2.8# per inch

[mnbwhtr]

Back in the day I shot a 32" draw I checked All of bows and they usually went up from 60# to 75# over those 4 inches. They were Bear T/D's and a Carrolls T/D but with the Carrolls you felt no stacking at all.

[Kirkll]

the main question is how many pound per inch does fiberglass gain or lose in draw.....now i know this is differant from bowyer to bowyer...my bear grizzly is 55 @28...but i draw 26"...i just dont know if its 2# or 3# an inch...thanks

Draw force curves are measured in pounds per inch and change a lot from one limb design to the next. It's not the glass that changes the PPI throughout the draw cycle, but the shape of the limb, and where the limb is bending.

You can have one limb design that has higher preload and the PPI in the first several inches will be 5-6 PPI, then drop clear down to 1.6 PPI mid draw, then slowly gets higher at the tail end of the draw.  This let off feeling makes for a smooth draw. Typical recurve designs do this as well as some hybrid long bows.

Other designs have lower preload, and a lot less PPI in the first few inches and a steady increase as the draw gets longer. Such as a D shaped long bow.

I would say your 55 @ 28" grizzly will be very close to 50# @ 26". it's probably about 2.5 to 2.75 PPI between 26-28". After 28" it will climb up to 3 PPI pretty quickly to 30" draw, and probably go higher between 30-31".      Kirk

[Russell Southerland]

I did not read any post, it depends on the Bowyer's design and the draw force curve there is no such thing as a standard.

[blacktailbob]

What Tim B said. end of story.

[TIM B]

Lol I’ve been watching this.  Almost strung up my 55# griz to test but that’s not the answer either….every bow is different
Tim B