Brand new tubes MB-450 and bias adjustment

I replaced all 6550 with Apex Matched JJ Electronics 6550 tubes.  Got all tubes installed and went to adjust bias and found that I could not reach the VTL suggested 250-300 millivolts, with many of the JJ tubes maxing out in bias adjustment at or a little above 200 millivolts.  I set them all to 200 millivolts and gave a listen and they sounded really good, but for many of the tubes they are at or near the maximum bias adjustment on the amp meaning no way to further increase bias if things change.  Has anyone seen this before on MB450 amps?  Maybe the JJ's need less bias adjustment than typical Russian tubes, or Apex matching was not consistent with real world conditions?

Do I return the JJ's and get Svetlana tubes and get bias to VTL recommended millivolt?  
What are you using to check the bias? Is it a DMM or a stick (analog)
A stick meter could be bad or lost calibration.

DMM could need batteries. or be set in the wrong position, (usually just the wrong data, scale).

1. Turn the unit off, pull the valves, turn the pots CCW (back them off FIRST)

2. If your using a stick meter get a 15.00 DMM Ace hardware special.
CRC, Check RE Check

3. Put the old valves back in and see if they bias correctly. If they do and your new ones don't. You got me. LOL Different ball game, wrong valve, weird valve...Vo doo, magic, gremlin.

4. Put the new valves in, warm up, turn the volume down all the way,
and bias the unit. CRC Check RE Check several times, left side right side, at least twice with new valves. Check again in about 40 hours, set them very close...

My older VTL, always said to check a resistor value, can't remember where it was, and IF they were within a given value, proceid, if not do X,Y,Z. Replace the resistors la te da... THEN

Number 1, 2, and 4

Thanks for the reply.  I am using a digital meter.  I put the old 6550 back in the amp and they could be biased easily to 250-300 millivolts.  Some have said the new tubes were too "cold" and to look for tubes with higher plate current.  I did try some SovtekWE with known current of 44 and these could be appropriately biased so I think I just need the tubes to be matched but select those with higher plate current.