I start threads about as often as I clean my barrels.
My question: I haven't cleaned the bore of my 243 in 6 or 7 years. Maybe more. It may have 50 rounds through it from then till now. Maybe more. Accuracy is still good. This is a fairly accurate rifle.
I have switched powders but basically nothing else has changed. It still hangs the bullets where I'm looking without a fuss. Should I clean it?
Ummm...
The question isn't whether or not you SHOULD clean your rifle (or any other gun), but HOW OFTEN you should clean it.
There are quite a number of people out there (myself included) who belong to the "use it, clean it" club. There are also quite a number of people out there who clean their guns, but not on so rigorous a schedule as the "use it, clean it" club.
And there are a few people out there who simply don't clean at all, unless something quits working right.
Cleaning firearms should be routine maintenance, and how frequently it's performed should, at the very least, be based on maintaining the condition of one's firearms in an undamaged state.
By "undamaged", I mean no signs of corrosion or other physical damage which can be attributed to poor cleaning and preservation.
If you clean your guns only after every hunting season and you've never had a problem with rust, pitting, or function, then it's safe to assume your habits are not detrimental to your firearm.
If, however, you start finding blemishes in the finish, permanent fingerprints in the metal parts, specks of rust, and whatnot, then I submit to you that your maintenance routine is somewhat lacking and your guns are starting to pay the price.
Like changing the oil in one's car, it's a sure bet that changing it TOO frequently will not ever be a cause for mechanical concern with respect to the mechanical health of one's car.
Likewise, not ever changing the oil in one's car is a sure ticket to early mechanical problems with one's car. It's not a matter of IF, it's a matter of HOW EARLY.
The same applies to one's firearms...don't take proper care of them and eventually they will suffer for it.
Clean your firearms as frequently or infrequently as you like...but DO clean them. Just take care to clean them often enough not to be the cause of damage to them in the long term.