TwiceBarrel, You are absolutely correct in your stated question! My thinking on the effect of these two forces on an OLDER gun may have been limited to the current and future use of the gun rather than it's past use. Assuming an "older" gun was used extensively with heavy shot charges and pressures common in the years following its' manufacture, recoil most certainly could have an effect on all parts you mention. If this were the case I would think that wear would show now, but perhaps not? In terms of current use of and older gun, appropriate ammunition should be used to prevent or minimize wear. Of couse most things that get used, even appropriately, wear. Speaking only for myself, my statements on pressure and recoil should be taken merely as a warning as to the possible result that could occur if some caution is not taken when choosing ammunition for a shotgun that may have been manufactured when lower pressure shells were used, but also keeping in mind that older wood may break and can be exspensive to replace.