.360 and .400 Deflection Converted to Poundage of Spine

[Steelhead]

i was curious if any one new what poundage as far as spine a .400 and .360 deflection carbon arrow has?

example .400=75# spine or .400=80# in spine.

I have shot mostly woodies and aluminum and have a few different carbons that a gentleman said had .360 and .400 approximate spine ratings.

I am more used to poundage ratings,not deflection ratings for spine.

my 2020s were 77#s on 26 inch centers,2018s 67 #s,2115s 70#s.These were listed on the Kelly bow charts as some of you guys will remember and or Foxfire Archery later.

Thanks

[JOEBO]

AMO Spine

.300 = 86.7
.400 = 65.0

ASTM

.300 = 105.1
.400 = 78.8

[Steelhead]

thanks for the response JOEBO!

[JOEBO]

I missread your first Question
.360 = 72.2
Amo spine is 2#@ 26"
Astm spine is 1.94#@ 28"

[Mike Burch]

What's .500?

[Fletcher]

52 lb AMO

[JOEBO]

Mike
Amo .500 = 52.0
Astm .500 = 63.0

[Steelhead]

Thanks again!

[SlowBowinMO]

Easiest way to do it is 31.5 divided by the spine.

31.5
-----   =  63 pounds
.500


That is to convert common carbon spines into wood/AMO ratings (26" centers).

[hayslope]

Stu Miller's calculator is a free download.  It has a converter built in that does all that for you.

Do a search on PowWow.

[Lucas K]

What is ASTM?
Lucas

[coaster500]

Stu's new revised version even accounts for arrow footings. He is constantly improving this tool.