I found a super 14 stainless barrel for my contender cheap.I have two big bore 94 barrels and I wanted to know how strong this contender barrel is?I have been able to push 220 gr hornady bullets 2400 fps in my 20 inch barrel will the contender handle this load.The load is 40 grs of aa1680.

May be safe in your gun but its 2 full grains over max from the AA loading data. I would stick to nothing more than max and even then working up to it would be a good idea.
http://www.accuratepowder.com/loaddata_caliber_rifle_standard_375cal.htm

Yep I worked them up with no pressure problems.I have even tried 300 gr Hornady FMJ in 375 win with aa1680 no problem.I would start with 35 grs of aa1680 in the contender with the 220 gr hornady bullets.I got the best accuracy with the 235 gr speer bullets with 36 grs of aa1680.

The SAMMI spec for the 375 winchester is 52,000 CUP

Given that this is a factory chambering for the Contender, one should be able to assume that the folks at T/C would have safety tested the frame for factory and proof loads.

Johnly wrote: "...one should be able to assume that the folks at T/C would have safety tested the frame for factory and proof loads."

Johnly-Never assume anything about the folks at TC. These are the same folks who have basically said that reloaders are idiots -- and the same folks who sell barrels with toilet bowl chambers and throats that run on forever. In fact, with factory .375 Win. loads in a TC-chambered barrel, I doubt the factory loads willl ever surpass 42-43000 cup...and the figure is probably even a tad lower than that.