Cure for Short-Stroking---Flex-Hone?

[Dr. Bullseye]

This 2 min. video popped up on my youtube suggestion feed. It is a honing device for AR chambers. Automobile cylinders can be honed to remove varnish and crud, making the engine work better but firearms? Does anyone know anything about this?

https://www.youtube.com/watch?v=bL808lxdEsA

[Iraqgunz]

LOL, someone doesn't have an understanding of the AR or how it works.

[26 Inf]

Dr. Bullesye - I've used Brush Research Flex Hones quite a bit - mostly on shotguns and the cylinders of engines when re ringing.

I love them for cleaning up the chambers on 870 expresses, and generally polishing shotgun bores - that is a different application than a rifle chamber.

I think they are good products, but, IMO, they are best for pretty much straight wall applications, not a tapered chamber with shoulders. Take a look at the .223 chamber brush picture at Brownells (click on the picture by the .223 selection and it will enlarge):

https://shop.brownells.com/gunsmith-tools-supplies/shotgun-tools/barrel-hones-accessories/ar-15-223-rem-chamber-flex-hone-400-grit-sku080001188-651-155078.aspx?cm_mmc=PPC-_-Itwine-_-Google-_-080-001-188&gclid=EAIaIQobChMI4ILx2qm54QIVkbbACh0gvAiqEAQYAiABEgLO8fD_BwE

Notice that even though the end of the brush is tapered, it isn't tapered to exactly match the chamber dimensions. Because of that more pressure will be exerted at the shoulder areas. These are abrasive hones, they will remove material if you go over board.

I think if you get a .223/5.56 chamber from the manufacturer that is rough enough to warrant polishing with a flex-hone, you need to send it back. Otherwise a good cleaning regimen is your friend.

JMO, worth exactly what you paid.

[Stickman]

This 2 min. video popped up on my youtube suggestion feed. It is a honing device for AR chambers. Automobile cylinders can be honed to remove varnish and crud, making the engine work better but firearms? Does anyone know anything about this?

https://www.youtube.com/watch?v=bL808lxdEsA

Like IG commented, its just not how it works. I'm not saying its impossible to polish the chamber, especially because its something that people who really want to obsess have been known to do, but a chamber brush is what is needed if there is varnish (or similar) and crud inside.

[vicious_cb]

LOL, someone doesn't have an understanding of the AR or how it works.

Remember back in the day where people put stainless steel chamber brushes on power drills to thoroughly "clean" their chamber. Why do I feel current M4C has regressed back to dark age levels of ignorance?

[Stickman]

Remember back in the day where people put stainless steel chamber brushes on power drills to thoroughly "clean" their chamber. Why do I feel current M4C has regressed back to dark age levels of ignorance?

Standard MP5SD cleaning method....

[Iraqgunz]

So to clarify a little. Yes, you can polish a chamber. That has almost ZERO to do with short-stroking. Short-stroking is almost always a problem with the gas port (size) or something misaligned (gas block). After that it comes down to leakage due to improper fitment (parts out of spec) or things like carrier key leakage (due to screw breakage) or weak shitty ammo.

[Dr. Bullseye]

Maybe I should have clarified my initial question: When would someone ever want to hone a chrome plated object?

[Eurodriver]

Maybe I should have clarified my initial question: When would someone ever want to hone a chrome plated object?

Probably because they just finished the wiping their car down with the window cleaning squeegee at the 7/11 and needed something else to ruin.

[curious1]

I have used the hones on non chrome and stainless barrels and they do as the video states. I doubt it would help on a chamber that was too bad off but it has worked for me on the ones that haze the case and start to have extraction problems after less than a 100 rounds. The first ones sold for the 223 did not match the chamber shape well but the newer design 5.56 one does. I have used both grit sizes.
Never tried it on a chrome or nitride barrel. Not sure how well it would work.

[T2C]

I have used the hones on non chrome and stainless barrels and they do as the video states. I doubt it would help on a chamber that was too bad off but it has worked for me on the ones that haze the case and start to have extraction problems after less than a 100 rounds. The first ones sold for the 223 did not match the chamber shape well but the newer design 5.56 one does. I have used both grit sizes.
Never tried it on a chrome or nitride barrel. Not sure how well it would work.

Have you measured the diameter of once fired brass both before and after honing? Did you see more brass expansion after honing?

[curious1]

Have you measured the diameter of once fired brass both before and after honing? Did you see more brass expansion after honing?

Never measured anything. The two grits are 400 and 800. From what I have read they really just flatten the sharp peaks and does not really remove enough material to worry. I would guess if you did it long enough it might have some significant dimensional effect.

[Uni-Vibe]

I've had to explain to two different people, why you NEVER lubricate the chamber, the bolt face, or the ammo. One guy thought it was a good idea to help feeding and extraction.

I explained about obturation and bolt thrust. I'm not sure I convinced anybody.

[BillB]

Probably because they just finished the wiping their car down with the window cleaning squeegee at the 7/11 and needed something else to ruin.

That's hilarious.

[BillB]

I use flex hones in my old revolver cylinder bores to clean up and pits and that's about it. I use them very carefully. Very quickly and very sparingly because they DO remove metal. That's what that grey liquid is that you clean out when finished, metal and the flex hone oil. Like when sharpening your knife, that grey/black stuff on your stone is your blade.
They have their place/use and I know they make a 5.56 chamber hone but I'm not aware of a situation dire enough to force me to use one in any of my AR chambers.