Just got my new 6.5 savage model 10 and it extracts the spent brass from the chamber fine but fails to eject it from the magwell. Whats the problem,weak spring ,bad ejector?

Unfortunately, welcome to Savage QC.
It can be one of a few things, but here are the typical suspects I order of usual failure:
--Extractor spring - Is weak and won't hold the case well enough to let the ejector work.
--Ejector - Can be a weak spring, or many times the plunger has some interference, a won't slide properly.

A quick fix to your problem is a larger dent ball to replace the small one under the extractor

Does the rifle have a scope with tall turrets mounted low?

My scope is mounted high in a one piece mount but my brass is still in the action , it just lays on top of the magazine when extracted

Since the extractor is able to pull the case from the chamber and the empty is not being bounced back into the loading/ejection port from hitting the windage turret, likely the ejector is not functioning properly. Just be sure that the one piece scope base is not covering any part of the loading/ejection port.

Take the scope and the mount off the rifle and see if you still have a problem. then work at isolating the variables one at a time.

I changed the detent ball this eve and it seems to toss it out now. Test run tomorrow hopefully its fixed

Shot about 30 rounds today in the snow and no problems with the ejector so far.