Will scraping the inside of the bolt carrier to remove the carbon build up cause damage to that part of the rifle? I believe it is hard chrome so I would expect that it would not unless you went crazy. I have seen posts on other sites which say YES and others that say NO. Some say they scrape it with a knife blade so I dont think that could be any less damaging than a dental tool.
Any advice would be appreciated.
Oh Man! You have hit on one of the deep dark secrets of gunsmithing.....the use of Dental Tools. :-) I learned a long time ago that every time I went to the Dentist to ask if they had any broken Dental picks that I could have. About 50% of the time the Dentist or the Hygienist had at least one. They are made of the best steel and can be reshaped and formed into all kinds of tools that are handy around the work bench. I had a fellow pistolsmith many years ago that became the envy of the trade when his FIL Dentist retired and gave him ALL of the dental tools including a couple of high speed drills. ........... Big Cholla
Anton, the very best way I have found to clean the bolt carrier is this:
Procure for yourself the following tools:
1. A cordless drill.
2. At least three cleaning rod sections from an M16 military cleaning kit.
3. A good number of chamber brushes.
4. Copious amounts of Hoppe's #9 solvent.
Thread the sections together, and screw a chamber brush on it. (Note..this is an M16/AR15 chamber brush.)
Wrap a good, thick towel around the outside of the bolt carrier to catch the gunk. Now, juice up the inside of the bolt carrier with the Hoppe's. Let it sit for a minute.
Chuck the cleaning rod with brush into the drill. It should be a VSR drill.
Put some Hoppe's on the brush; now push it carefully into the insider of the bolt carrier. While running the drill at medium speed, push the bore brush all the way in; the skinny part will go through the cut-out in the bottom, and the fat bristled part will be sitting inside the bolt carrier--which it right where you want it.
Run the drill for a couple of seconds, then withdraw while it is still turning. Flush the bolt carrier out with Hoppe's and look into it. It will be cleaner than you could ever get it with dental tools. Dry out with clean cloth, lube and you're done.
HINT: You can do the same thing with the chamber of the AR15/M16, as well. Just don't run the brush down the bore, or let it get past the chamber. Some Hoppe's in the chamber lug area and the brush treatment leaves it pristine.
I've always used the dental picks on the hard carbon build up, but never really scraped that hard. I like Powderman's process. For the lug recesses I haven't found anything that works anywhere near as well as the cleaning stars. I would have literally given my wife's first born child for a few of those in the desert!
The OP said "Bolt carrier"...I would NOT use dental pics in the carrier, especially where the sealing rings ride like a Cylinder. I would use carbon solvent/mineral spirits/ or PB Blaster and bronze brushes for cleaning the carbon out of the carrier and Key.
I got lazy and aquired a sonic cleaner. Trying different fluids in it. So far, Graymils Aquaclean does a fair job, It's aqueous so the parts have to be dried and oiled after use. It works. My unit is from harbor frieght, Chicago electric.
I took a .270 cal bronze brush and bent the tip and looped it around. I used .270 only because that is what I had available. This worked really good and got to the hard to get places. I also used Hoppes. Then I rinsed with CLP.
Call me behind the times, but I have never given a thought to cleaning that part of the carrier or the back end of the bolt. The carbon and stuff gets blown off of it when it gets too much, and protects the steel from the hot gasses.
I have not had any issues with cycling or ejection and such.