A clean gun, one that functions properly, is worth more than a rusty one. |
The biggest culprit is plastic residue left in the barrel. Rust develops underneath that plastic and can pit the barrel. Besides that, recoil increases. Extraction of the shell is less efficient, especially with the semi-automatics. |
Upland hunters might have something as simple as a weed seed that has worked into the gun, into the trigger group or the bolt, causing a malfunction. Maybe a bur has developed on a part. |
We see more and more guns not getting routine maintenance. At the end of the season, (a hunter) should clean the barrel of all that residue and lightly oil it; external surfaces, too. |