[Charlie]

I understand.... somewhat. It just seems like it would have been easier to stick with nice round numbers stamped on the component such as 20 instead of 22, or 30 instead of 33.

Often, I do notice that multi-section cans give readings that are a good bit higher than the value on the can, but still within the 20% tolerence. Individual electrolytics, I've noticed, are typically spot-on what the stamped value is.

The example of the 51 ohm NOT having a 10% tolerance makes a lot of sense. I would think if it circuit calls for a 51 ohm resistor, it needs to be 51 ohms... or really freakin close.

I recently went thru a lot of resistors I got a while back. They were all nicely cataloged in small mailing envelopes with value, wattage, and tolerance written on the envelope. There were at least 75 different values... most of which were somewhat odd... 91, 110, 18, 13, 34... and so on. They were all 5%. Just so happens... as I am looking at them, there's a 51 ohm 5% envelope (as in your example) that's staring at me.