Gunsmithing Polishing New Chambers
- Thread starter Edds
- Start date
If anything, I use fine sandpaper very lightly to give it a “crosshatch”. I have never tried to polish a chamber after reaming.
Everyone I do. During the life span of the reamer the finish changes. Also not all reamers cut the same when new. Below is the face of a flute in the body area.
I woudnt call call it a polish, but I smooth them out. Easy to do, and doesn’t change dimensions at all. I think the theory that the case needs to grip the walls is somewhat true, but wildly overstated generally. I’m new at this so maybe I’m wrong, but I can’t detect any negatives. Brass sure comes out looking nice.
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I think that's one of many old wives tales. Brass will flow when 62K PSI is applied internally.
Do you find it flows less up neck in length if chamber is not polished like a mirror?
I think brass flow has more to do with shoulder angle and how well the FL die and chamber match up. I don't have a mirror finish in my chambers but I polish enough that I don't violate rule #1. That means don't do anything to make the phone ring. Rings on brass make the phone ring. The roughest part of the chamber is the shoulder area. So if a rougher finish is supposed to prevent brass flow, it's not working for me.
ive done tests with lapping and polishing chambers......didnt notice any difference in accuracy.
i just use a nice fresh chamber reamer, cut it, and leave it.
if my reamer is leaving a shitty chamber.....time to get a new one.....
i just use a nice fresh chamber reamer, cut it, and leave it.
if my reamer is leaving a shitty chamber.....time to get a new one.....
https://www.varmintal.com/a243z.htm
More than you ever wanted to know about chamber polishing and bolt thrust.
More than you ever wanted to know about chamber polishing and bolt thrust.
320 grit. 400rpm. 60/30 crosshatch. Make it resemble a honed bore. The brass bites without frosting with this grit. You want this as it helps mitigate case growth.
I always finish with wet or dry (wet) 220 if the reamer is worn, and finish with 400 wet or dry paper.
I also polish the free bore and lead angle. Surface finish make a lead angle last longer. Ends up with 3 aught emery in the leade area.
Alan
I also polish the free bore and lead angle. Surface finish make a lead angle last longer. Ends up with 3 aught emery in the leade area.
Alan
