Black pads have barrels made in house that are across the board dependable. The red pads had outside contracted barrels that were mostly good but had enough bad ones to give the #1 a bad name for a very long time.
Wood is usually nicer on the early to mid range red pads and fitted better to the metal.
wunbe
I agree, but will add this:
1. Rifles below serial number 130-05000 will have Douglas Premium barrels and are essentially hand fitted rifles. After that number Ruger used Wilson barrels and the QC was not where it should have been. Ditto for stock fitment and other details. All of my rifles below that number shoot really well. After that number it's a mixed bag, with some shooting very well, and some only so-so.
2. Beware of 'salt dried wood'. It shows on some rifles in the 1975-1977 year range. You can tell it by a thin line of rust growing between the stock and action. Other manufacturers including Browning also had problems with it. Salt was used to dry the stock faster, but it's a terrible problem when installed on a rifle. Ruger did not do it, their supplier did it. I don't think they could tell when they installed it. Unfortunately some of the prettiest wood installed on No. 1s was salt wood. Don't get distracted by the gorgeous wood and end up with a rifle that has corrosion in the action and finish. Especially be careful when buying based on pictures.
JMHO
Jim