Many of the older inlines and traditional muzzleloaders that I see in pawn shops,gun stores and on Gun Broker show pitting around the receivers and locks. I realize that barrel pitting is most important for accurate shooting,but a pitted receiver or lock certainly lowers the value and detracts from the looks of a gun.My assumption is that the pitting close to the nipple is related to both blowback from the powder charge and the cap or a combination of both. Most muzzleloader shooters fire caps prior to loading to clear the firing channel ;and some like Doc White also fire squib loads before loading.So the preloading procedure leaves a corrosive deposit around the nipple area that is also exposed to weather and moisture during a hunt.Other than hunting with an oiled fire channel which leads to other problems or some other precleaning option that I am not aware of ,there seems to be no easy answer.My own solution is to hunt with a alcohol cleaned bore and fire channel,but the problem of first shot flyers is still there.The many pitted receivers and locks that I see say that no easy answer exists,but I would be very interested in comments from those of you with more muzzleloading experience than me ,which is likely everyone reading this. Thanks for your comments. steve

When I hunt with a side lock I fire 3 caps with no powder before loading. I have never found any rust or pitting when the load is not fired and left in the gun for a prolonged period of time.
I just fired a round that was in a caplock pistol today that had been loaded that way. That load had been in the pistol since November and when I cleaned it today the barrel looks brand new and shines, no rust.
I do not recomend you do this but it works for me. I have actuallly left a load in untill the next season that was loaded this way and still had no rust.

I think pyrodex is the culprit a lot of times when you see that pitting in the receiver. That stuff works fast.

Yes I agree.