Tips for cleaning ANY weapon...
1. Shower - It works, if you use hot water (any water works if you're washing out sand or mud.) We were actually instructed to clean the 60mm Mortar in the shower and then wipe it down with Varsol.
2. Baby Wipes - Preferably "Wet Ones." Non-abrasive, highly useable, and they get carbon off C6 / C9 gas parts in seconds. Also good for field baths / getting campaint off before returning to garison. After using them on a weapon, though, be sure to give it a coat of CLP.
3. Brake cleaner - Haven't tried this: mil-surp rifle collectors swear by it (gets carbon off anything.) Guys I've talked to who did their PLQ like it too. Warning: don't confuse brake cleaner with CARBURATOR CLEANER! Carb cleaner is abrasive (strips blueing off of metal and can corode some plastics, ie the plastic handguards.)
4. Mixing CLP and Naptha - Works good on a hot day (and when getting 10 C9s clean in 1 hour with a fireteam partner is your only option.) CLP draws the carbon away from the parts, Naptha evapourates. Weapon wipes down easier/faster. Only recommended for a VERY HASTY cleaning.
5. Steel Wool - BIG NO NO! Unless you're cleaning slightly worn parts with no blueing (read hollow portion of C6 gas piston.)
6. Air can and paint brush - Good if you're in a dry dusty environment where your weapon won't be as oiled as usual (read Arid regions, or Petawawa during the summer.)
7. Coke or pepsi - Work really well for cleaning caked-on stuff on bolt / gas parts. Simply put parts in a container, fill it with a fizzy can/bottle of Coke or Pepsi, and clean something else for a while. Then pull out the parts, dry and lightly oil them, dump the oily Coke down the toilet, and Bob's your Uncle. Mechanics at my local garage do this with tools that start to rust (works like a charm.)
8. Bore Snake (insert calibre here) - One pull-through with this is like 50 pull-throughs with patches and jags. And the boresnake is water / machine-washable too. And, "gasp" it kinda looks like a Gartner Snake!"
These are just a few of MANY: these being more common around me. Try 'em out; see what works for you.