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Gray Mark


I am assuming that this is a 'blued' GM barrel, and that the "gray mark" is on the breech face....? ?

If so, it is a combination of the bolt / breech contact and powder fouling...! ! Not to worry...! ! ;)

When firing my S&W K-22 revolver, the forward face of the blued cylinder gets a ring around each chamber; this is a combination of powder fouling and leading...! ! :eek:

Remember, the 10/22 is a "blow back" action: the recoil and hot gasses of firing a round push the bolt rearwards, and as soon as the mouth of the case clears the chamber, the powder gasses blow out into the action; the returning bolt slams these gasses, and the debris they carry, against the breech face of the barrel, grinding the debris into the pores of the steel...! ! :(

It is not a problem...! ! ;)
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