Red Wing’s retail presence in the US leads to them being a common first boot for many people. Unfortunately, many people are fitted incorrectly and end up with boots that are too small, because salespeople are not trained to have a good understanding of fit and sizing. This is a common problem with many brands, but it is particularly bad with Red Wing. In addition to a lack of training, Red Wing’s lasts tend to be narrow but high volume. This high volume makes people think that they should size down more than is appropriate.
A recent development that has made things worse is the replacement of their in-store Brannock devices with Volumental scanners. These scanners should not be used to size people for welted footwear, as they do not give you the most important measurement of all: the heel-to-ball size. If you are reading this and do not know your Brannock size in detail (heel to ball, heel to toe, and width, for each foot) I strongly recommend reading the Brannock page before proceeding any further.
The goal of break-in is to get the sole used to flexing at its natural flex point, not to suffer through the pain of a boot that is too small. If you are experiencing pain, you should stop wearing the boots and consider sizing up or looking at other lasts from other makers.