They will get....

[Hawken]

filthy if not torn down and cleaned!

Untitled by Sharps Man, on Flickr

[prairie dog]

That's why I pull em every time. 

[rollingb]

That's why I pull em every time.

Cleaned AND oiled.

[Hank in WV]

I hope that didn't happen after one round at the range. If so, that lock is not fitting the rifle very well.

[Uncle Russ]

I hope that didn't happen after one round at the range. If so, that lock is not fitting the rifle very well.

Although I pull mine and clean 'em good after each range session, I've never seen one that even looked like it was actually dirty.

I wash 'em with a small pan brush, shake 'em good, then and wipe 'em dry, and then I use 3-in1 Oil on a cloth wiping good with a drop here and there.
I'm with Hank on this one, that looks more like a few years of shooting, rather than just one, two, or even dozens of  Range sessions.

Hawken, I sure would like to see a picture of the lock after it has been cleaned.

  That picture makes me want to go pull all my locks and look 'em over, it has been very close to a year since I last shot any of them.....God only knows what may be going in inside those guns....lol

Uncle Russ...

[Hawken]

I hope that didn't happen after one round at the range. If so, that lock is not fitting the rifle very well.

This was after an eight month period of on and off shooting! I didn't clean it on purpose because I wanted to see what it would appear as after many rounds of firing! I dropped this into a bucket of warm soaping water and just shook it around and made photo. I had not used my brush on it and it cleaned up quite nicely! Reoiled and ready to go again!

Untitled by Sharps Man, on Flickr

[Ohio Joe]

I'd might be a bit concerned about metal to wood fit of that lock.

[Uncle Russ]

I hope that didn't happen after one round at the range. If so, that lock is not fitting the rifle very well.

This was after an eight month period of on and off shooting! I didn't clean it on purpose because I wanted to see what it would appear as after many rounds of firing! I dropped this into a bucket of warm soaping water and just shook it around and made photo. I had not used my brush on it and it cleaned up quite nicely! Reoiled and ready to go again!

Untitled by Sharps Man, on Flickr

That's much better
 "8 months of off and on shootin" is a fair bit of shooting without any cleaning, IMO.
The 1st picture looked to me like there just may be some pitting once it was cleaned up, but that 2nd picture proved me wrong on that point.

Uncle Russ...