Realized I posted this "Sticking Buffer" in Bulid it Yourself  - could a mod please move ? Thanks
www.ar15.com/forums/topic.html?b=3&f=4&t=222847
If anybody has other ideas of what the issue can be it would be appreciated .
GotM4 did send me out a recoil spring ( recieved today ! ) and it fit better and was 1/4" shorter but did not work still .
I've checked for:
free travel of the bolt carrier
free travel of the buffer
buffer retainer
firing pin retainer
 other than weight , (by cheap caliper) the buffers are alike in  length with only .010" difference at shank
What else would cause a 2.9 oz buffer to work and NOT the 5.47 oz buffer ?  

Few things I would check. I would check to see if it would compress without using the upper. That the buffer would drop in and out ok with no spring to see if it was binding in the tube. The spring to make sure it was not to tight and would not compress without catching at the bottom edge were the plastic and steel meet on the buffer. That the inside of the tube was not rough and catching on the edge of the head on the buffer. If it was a two piece the pin through the pieces was not catching the spring.

Good timing ! Just got donewith a triple check of just those items . Still the spring is the problem .
Slid it onto the buffer, as much spring as i could hand compress on and it bound up still .
So this is my temp fix . Grab the spring with gloved  hands and "untwist " to make the inside dimension bigger still .
Guess what ? It friggin works !!
Test fire at the range this weekend to see if it is shootable .
At the next funshow I will have calipers in hand to search for the perfect spring .
Thanks All  

Like I mentioned on the other post I bought a couple of the chinese springs from Tapco because they are bigger on the inside measurement and they work on my buffers.

Tapco !? I hadn't thought about them , Thanks !  

Range update : 400 rds with the 9mm buffer and "untwisted" recoil spring - everything worked as it should . No failures . Thanks to all who offered help .  
At the range again on 2/19/05 - 200 more with no failure . Probably not a SHTF solution , but it seems to work .  

TAG