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triggerjerk
10-03-23, 12:08
What are the inner diameters encountered as you progress from front to rear of a 556 bolt carrier? I want to get cleaning brushes in the correct diameters (9mm, .410, etc/whatever) to efficiently scrub each section inside the carrier. Thanks
HKGuns
10-03-23, 12:25
The bolt dimensions are:

.5280 +/- .0005
.511 +/- .004
.488 +/- .002

That said, I don't use brushes, I use the CATM4 tool with a patch after 10 minutes in an ultrasonic. Gets them squeaky clean.
Disciple
10-03-23, 12:39
The "Mirror Link" worked for me. https://pdfcoffee.com/download/m16-bcg-drawing-set-pdf-free.html
1168
10-03-23, 20:35
You can use a .45 brush on a drill with some CLP, but its completely unnecessary. Using the small end of a GI toothbrush once in a blue moon with some CLP, you can go longer than the life of the gas rings before needing to clean more thoroughly. Probably longer than the life of the bolt.
triggerjerk
10-04-23, 07:33
Wish I had a US cleaner. Will look up the cat tool....

Dang, Disciple. You called my bluff. Gotta find something bigger than my phone to read em!

Yeah, not looking to scrub spotless. Just want to wrap a patch and turn by hand for more efficiency than stuffing a patch inside. Easier to wrap a new patch on a brush than deal with a bore mop. Hosing with clp/brake cleaner leaves more than desired....

Size for "firing pin tunnel"?
markm
10-04-23, 08:46
Wish I had a US cleaner.

Those things suck. I blotched the finish on a Colt Carrier trying that nonsense once. No functional damage, but annoying.
HKGuns
10-04-23, 10:25
Those things suck. I blotched the finish on a Colt Carrier trying that nonsense once. No functional damage, but annoying.

What did you have in there Mark? I've used one for years and have never had an issue with a finish. I use mainly water with either Simple green or Hornady US cleaner fluid added at about an 40:1 ratio. (Water:Cleaner)

I certainly don't toss my blued Smith's in there, but stainless, phosphate, NP3 or just about any other coating turn out great.
markm
10-04-23, 11:17
Just water. I never added anything fancy to the solution.
1168
10-04-23, 11:51
They’ll take the color out of the markings on a MP5 as well.
HKGuns
10-04-23, 12:07
Yep, they'll certainly take off paint. They can also mess with your skin cells, if you own one, don't stick your fingers in there while it is running.
Dutch110
10-04-23, 12:30
Yep, they'll certainly take off paint. They can also mess with your skin cells, if you own one, don't stick your fingers in there while it is running.

I need to get educated on sonic cleaners. Ever since I started running cans, well, you know what happens lol. What I need to figure out are the limitations ie what can and cannot go in there. If it were up to me Id put my 22 polymer pistol in there after every range session running suppressed.
1168
10-04-23, 12:44
Yep, they'll certainly take off paint. They can also mess with your skin cells, if you own one, don't stick your fingers in there while it is running.

They get used to clean the flesh out of surgical instruments’ teeth.
markm
10-04-23, 12:50
We had a helicopter parts company that contacted our company because they wanted distilled water to run in their U/S cleaner(s). I never tried pure water... just tap water. I just don't feel like dragging out that worthless piece of shit again.
HKGuns
10-04-23, 12:55
I use it to clean the baffles on my can. Pop them out and they don't come out perfect, but really good. I do not put the shroud in as it is painted.

I use mine for most of the parts you remove from an AR to clean. [BCG - Bolt - Extractor - FP - Springs - etc....] - I do not put AL into it, but understand it is safe.

I also use it for the parts I remove from my pistols when cleaning. [Barrel - Spring - Bushing - Stainless cylinders - etc.] - I do not put polymer into it, although I am pretty sure you can safely. I have done a few slides with no harm as well. Mostly the HK models with their finish. Again, no blued stuff of shiny stuff.

After they are cycled through I soak them in kerosene to get any water out of the small spaces for a short time.

All of this happens on the side while I am working on the barrel / receiver. You could serve a meal off the inside of my BCG's in most of my rifles.
HKGuns
10-04-23, 13:05
We had a helicopter parts company that contacted our company because they wanted distilled water to run in their U/S cleaner(s). I never tried pure water... just tap water. I just don't feel like dragging out that worthless piece of shit again.

I just use tap water, so I don't know if it would make any difference.
markm
10-04-23, 13:15
I just use tap water, so I don't know if it would make any difference.

Not sure what the reason for needed distilled water. U/S function or Residue on the parts.
HKGuns
10-04-23, 13:17
Not sure what the reason for needed distilled water. U/S function or Residue on the parts.

Based on where you live, you may have minerals in your water I don't.....I'm sure that is potentially a difference.
1168
10-04-23, 13:23
Based on where you live, you may have minerals in your water I don't.....I'm sure that is potentially a difference.

DI water is a more potent solvent due to less valence electrons tied up with other atoms. Or so I’m told.
markm
10-04-23, 13:32
Yeah. Phoenix area water is hard. Lots of dissolved solids.
Uncas47
10-04-23, 14:21
I usually add more oil, I have lots of oil.