I hate to say it, but you are wrong here...Excal does not make, or sell a 350grain arrow.
I think they came real close at one time.
The GT's that came w/ a Right Stuff package I bought in 2004 [?] weighed 357 gr and I got 350 fps out of the Emax I shot them from. They had alum inserts and nocks and 5" vanes.
I know they changed from them somewhere along the line, but not sure when or why.