I need a little help.  I'm looking at using a threaded rod in pure tension.  The application calls for a 7/8" diameter by 10" rod in which A36 material is insufficient.  According to the AISC manual, the only materials readily available in round stock are A36, A572, A588(?) and A449 (I don't have the book in front of me, so bear with me if I left out one or two).  A449 is the only material sufficient in strength for my case.

I have met resistance from our suppliers with this spec.  They are saying we should use A193 Gr 7.  This resistance baffles me and brings me to the following questions:

1)  Why is A193 Gr7 not listed as an allowable material for threaded rod applications in the steel manual?  According to ASTM, the strengths are acceptable.  So do I ignore the allowable materials listed by AISC?

2)  Why are our fastener suppliers giving resistance for an A449 threaded rod?  I know these are commonly used for anchor bolts which require a high strength.  

If anyone could help point me in the right direction, I would appreciate it.