The manual for my Marlin 917v states very clearly that the gun does not require regular cleaning with normal use. That it really only needs to be cleaned after heavy use. The barrel on mine stays very clean and I hardly clean it.
When i do clean it I will run a swab with some cleaner and it comes out with a tiny amount of residue. Run another swab through it and it comes out as white as it went in.
Also my Marlin 917v cost me about 250 dollars and I put a redfield scope on it that cost around 200. I replaced the trigger return spring with one taken out of a bic pen and cut to the same length. It has been utterly dependable in putting bullets exactly where I want them to go.
If anything I find that my groups shrink in size as I shoot, my accuracy 25 rounds in will be better than my first shots from a clean rifle. The group above was around 65 yards and 4 shots, shooting prone off a bipod. This was probably 20 rounds in since I had stated shooting, no telling if the rifle was recently cleaned or not.