Not true, just requires more cleaning due to lead residue

 

They will clog a gas tube up if you fire enough .22 LR rounds through it before you fire some 5.56.

 

Cycle a few 223 or 556 every few hundred rounds. And a good cleaning every 800 to 1000. You should be GTG.

 

Good advice, and what I normally do.

In the instance my gas tube got clogged it was someplace between 1,000 and 2,000 rounds of lead (not copper washed) .22 LR before I went to fire some .223/5.56 through it, and they would not cycle. I was teaching a group of scouts to shoot and the AR was very popular. It was a pretty simple fix, but not something easy to do on the range, when I got home I knocked out the roll pin holding the gas tube in place, removed the gas tube, heated the end of the gas tube up with a propane torch and when the lead/grease mixture started to drip out I blew through the other end of the gas tube. Put the gas tube back in and went back to the range to fire some .223/5.56 through it and all was good.

Since that time I pull the conversion kit out and put a couple .223/5.56 through it every couple hundred rounds or at the end of a range session.

 

Stick to copper plated .22s and end the range session with with a mag of 5.56 to blow out the gas tube. That's what I do and have never had any problems.

 

I seem to get a fair number of misfeeds. I have only used mine a few times though, so maybe it's the mag springs needing to be broken in. Anyone have the same problem?

 

Delete

 

There is another option with the best .22 dedicated upper on the market. 22RB Dedicated 22 Upper - Nordic Components

If you already like your AR lower this is a great combo.