Gunsmithing Chambering question

[Skeet375]

I am trying to build a .308 on a Remington action. I just got "The Complete Illustrated Guide to Precision Barrel Fitting" and I had a question. It sounds like in the book when you chamber you use the rougher for about 1/4 in. then switch to the Finisher to cleanup. Then go deeper with the rougher and repeat. My understanding was that you roughed then finished the last .050 with the finishing reamer. His explanation if I understand correctly is that the pilot won’t be guiding off the bore. Is this right. Thank you

 

[wnroscoe]

Re: Chambering question

Use a finish reamer from start to finish. At first, ream in .100" and clean the chips off the reamer and out of the chamber, use an air compressor to blow out the chamber and to blow the chips off the reamer. Keep the reamer and chamber flooded with a high sulphur cutting oil. Keep the reamer pilot clean and chip free. Watch for chip weld on the reamer flutes and keep them clean as well. Towards the end of the chamber, about the length of the neck and shoulder, ream in .060" or less, clean, re-flood, ream.

Excess Reamer heat is bad juju for good chambers, use plenty of the sulphur based cutting oil, don’t skimp.

 

[300sniper]

Re: Chambering question

i am happy with drilling then boring the bulk of the material out of the chamber then finishing with a finish reamer. i'd skip the rougher all together.

 

[Clark]

Re: Chambering question

When I started out 9 years ago, the gunsmith tech adviser at Brownells told me to skip the rougher.

I have never used one.

For big chambers to cut, like 300 Win Mag or 243, I drill, true with a boring bar, and then finish reamer.

For small chambers to cut like 22LR and 223, I do it all with the finish reamer.

I might do it either way with a 308.