[rattus58]

The numbers of the 2016 and the like express shaft diameter and wall thickness. 2016 = 20/64 and .016 wall thickness. I'm assuming the 500 = 2016 refers to a carbon shaft of equal spine.

Spine is the "bendability" of the arrow, or maybe more accurately, it's resistance to bending. On a traditional bow, where there is a riser from which the bow is launched, whether off the shelf or off a rest mounted on the riser, that arrow will bend as it accelerates. If it bends too much, you have a weak arrow and it will fly off course generally to the right of your target from bending too much (right handed shooter).

Conversely, with a too stiff arrow, you will not get enough bending, and it will generally shoot to the left from the same bow.

Looking at spine charts is relatively easy.

2412 S 299 A
2314 S,75 330 A P
2215 S,75 331 C
2117 S,75,E 373 B P
2216 S,75 373 A
3-49 ACC 271
2-49 HSpd 222
400 ICS-H 250
400 EVLN 276
410 RDLN 245

This is copied from another site.... 2314 and 2117 would be the popular selections, A would be a hard spine, B would be softer, and C would be the softest. Middle common is arrow type and right column is arrow weight for a 31" arrow with a 100 grain point on it.

Arrow Length: From string groove in nock to back of point.
Bow Wt @ Your Draw

-------25"- 26"- 27"- - 28" - 29" - 30"- 31"
30 lb 1616 1616 1716 1816 1816
35 lb 1616 1716 1716 1816 1816 1916
40 lb 1616 1716 1716 1816 1816 1916 1916
45 lb 1716 1716 1816 1916 1916 2016 2016
50 lb 1716 1816 1916 1916 2016 2016 2018
55 lb 1816 1916 1916 2016 2016 2018 2018
60 lb 1916 1916 2016 2016 2018 2018 2020
65 lb 1916 2016 2018 2018 2020 2020 2117
70 lb 2016 2018 2018 2020 2020 2117 2216
75 lb 2018 2018 2020 2020 2117 2216 2219
80 lb 2018 2020 2020 2117 2216 2219 2219

Aloha.. :beer:

 

[Viper1]

gbgt -

IIRC a 300 is a 2317.

The new (500, 400 etc) number are relatives deflections in inchs, ie a 500 deflect .500", but the numbers are nominal at best.

As to your other question is it a 29 or 30" draw and what arrow length are you planning on using?

Viper1 out.

 

[dbgt]

-well i did some searching around and going with the wingspan/2.5 i got 31", but when i actually pulled back the string on the bow and had someone measure where it felt comfortable it was 29.75" that is to the front of the riser.

-I am still searching on and trying to learn about the form that you should try to use when shooting. so i am not sure excatly where and how everything should line up.

-Thanks for the responses thus far

 

[trapperDave]

I'm going to make an assumption here...

assuming the bow is 40 @28", so your pullin about 45lb at 30, so you gonna need a 2016 or its equivalent.....assuming your gonna put about 125 gr up front. If youre gonna use a heavier head...youll need a stiffer arrow.

 

[Kinetikx]

I'm going to make an assumption here...

assuming the bow is 40 @28", so your pullin about 45lb at 30, so you gonna need a 2016 or its equivalent.....assuming your gonna put about 125 gr up front. If youre gonna use a heavier head...youll need a stiffer arrow.

Not that it matters much since I'm very much a beginner at all of this stuff but I'm going to agree with TrapperDave on this one just because that's the arrow I decided on for my longbow which hopefully should be about 45# @ 30" when done.

Not to hijack the thread too much but I'm still unsure of how point weight will effect my accuracy with this bow and arrow combination. I've ordered some 75 and 100 grain field tips so I'll be doing my own experimentation, but any info you guys can add would be helpful at least to myself and hopefully also the OP.

 

[Viper1]

k -

For all but the hightest levels of shooting, it takes about 45-50 grains for show a 5# difference in dynamic spine.

Viper1 out.

 

[alanraw]

OK. Is the bow listed as being 40#@28"? If so, as trapperdave said, at your draw length, it'd probably be around 43#-46# or so. I would probably go with 1916s, myself. Maybe 2016s. I'm not sure...and also, you should always use feathers on a traditional bow shooting off the shelf; you can use vanes if shooting off an elevated rest, but I have no idea of your setup, so...