A36 is a generic mild steel. Does not heat treat. Period. 5160 is a mid
range carbon (.56% to .64%), low alloy steel that will heat treat to a
midrange but not like the high carbon spring steels. If you need 5160,
keep looking.

Check here for the full specs:
http://www.matweb.com/index.asp?ckck=1


sbrowder wrote:
Can A36 be spring tempered? If so how well does it perform compared to
5160?
Or should i just keep looking for a local supplier of 5160?
TIA
Scott