Chamber Cast of an AR Barrel: Anything I Should Know?

[RG1911]

I've ordered some Cerrosafe from Brownell's to check the chamber dimensions of my AR-10 in 260 Rem to see if the extraction/fail to extract problem stems from an undersize or damaged chamber, or just all the dirty smoke being blown back through the action by the silencer.

Does anyone know if there are any particular tricks to melting and pouring the Cerrosafe past the receiver and into the chamber?

Thank you,
Richard

[lefty o]

id for sure remove the barrel from the rcvr.

[RG1911]

id for sure remove the barrel from the rcvr.

Undoubtedly the best method, but I don't have the tools necessary to do a good job and have no intention of bubba-ing the job.

Cheers,
Richard

[KLR]

Pack aluminum foil under the locking lugs so that cerrosafe doesn't get under them. Then make a funnel out of an old piece of brass or a piece of aluminum pop can. It's not that hard to do and a heat gun will come to your rescue if you do get it under the lugs.

[RG1911]

Pack aluminum foil under the locking lugs so that cerrosafe doesn't get under them. Then make a funnel out of an old piece of brass or a piece of aluminum pop can. It's not that hard to do and a heat gun will come to your rescue if you do get it under the lugs.

Much appreciate that advice. I had not considered the space under the lugs.

Cheers,
Richard

[cwlongshot]

Undoubtedly the best method, but I don't have the tools necessary to do a good job and have no intention of bubba-ing the job.

Cheers,
Richard

Proper tools are not expensive (Unless you have funky proprietary hand guards)

Plastic action block that you put in a vice is available from Cabelas and many well stocked shops for 25 - 35$ MagPul makes a little better BEV block for about 75$ Then regular wrench in the 1 1/8" size many barrel nuts are. A good adjustable will suffice. Watch UTube for a good reference.

Also I would be sure you don't fill too much, stay clear of the breech with the melt, serves no purpose anyhow everything important is form shoulder forward anyway.

Good luck

CW