Chamber flaw help

[shepherm]

Can you guys help me understand if, and how, I cause this flaw in a chamber I cut? It runs about halfway around the chamber. Thanks for your advice

 

[riflewoman]

Picked up a chip in your last ream. All you can do is et tge batprrel back one turn and try again.

 

[Ggmac]

Agree with riflewoman . A better picture would be nice . Did you feed the case from the mag ? I ask to eliminate any feed issues , primary is a sharp edge at the end of the chamber . If so a better pic of barrel end . I could just need a better chamfer .
Sorry no coffee yet , I hope this makes sense

 

[GenePoole]

This looks like a chip roll. A chip gets jammed between the reamer cutting surface and the inside of the chamber being cut. Something has to give. Usually the softer metal (chamber) gets gouged, else, the reamer breaks. A picture of the chamber would probably show this much better. Judging by the other concentric lines on the case, it should be pretty obvious looking into the chamber.

 

[Dusty Stevens]

You reamed way way too much without clearing your chips. That whole chamber is ruined.

 

[Ledd Slinger]

Can also see other ring marks on the brass in front and behind the big gouge. Definitely had chips stuck on the cutting edges of the reamer and maybe some chatter going on.

I've watched good smiths reaming chambers (as I hope to do my own someday). It takes them a very long time to complete a chamber as they only run the reamer in for very small cuts before pulling and clearing chips. Maybe only .010"-.030" at a time depending on the size of the reamer. Tons of cutting oil used and tons of in and out with the reamer to ensure the cut is super clean. They also drive the reamer in slowly and their hand never leaves the wheel of the tail stock so they can "feel" if something doesn't seem right. Many also place a finger on the back of the reamer itself for better feeling.

 

[shepherm]

Thanks for your feedback. I pulled the barrel and did find the problem. I think you guys are right and I must have gotten a chip caught. Now I get to try and fix the problem.

 

[savagedasher]

Try polishing it out looks like it out rathe then in the chamber

 

[Ggmac]

Can also see other ring marks on the brass in front and behind the big gouge. Definitely had chips stuck on the cutting edges of the reamer and maybe some chatter going on.

I've watched good smiths reaming chambers (as I hope to do my own someday). It takes them a very long time to complete a chamber as they only run the reamer in for very small cuts before pulling and clearing chips. Maybe only .010"-.030" at a time depending on the size of the reamer. Tons of cutting oil used and tons of in and out with the reamer to ensure the cut is super clean. They also drive the reamer in slowly and their hand never leaves the wheel of the tail stock so they can "feel" if something doesn't seem right. Many also place a finger on the reamer itself for better feeling.

Awh come on , just take out the makita drill , stick the reamer in and MOST important part , raise the barrel up so the chips fall out from gravity itself .
Easy Peasy , that's how to rea

Thanks for your feedback. I pulled the barrel and did find the problem. I think you guys are right and I must have gotten a chip caught. Now I get to try and fix the problem.

glad you found it , go in less before cleaning chips from reamer and chamber , I use dark sulphur cutting oil , and run about 90 rpm and clean every .025-.045 , the deeper you go the more I clean , after all each flute is cutting the entire length now .
Good luck .

 

[Danny1788]

Use a flush system. Never rolled a chip yet. I don’t have some fancy expensive setup, but it clears chips very well. I pre bore and ream the chamber at 200rpm

 

[Shawnba67]

@shepherm
Just curious, was there a physical problem? Or just a visual spot on the fired brass?
I have a fireform barrel with a similar ring, it doesnt cause me any issue. At least any issue Im aware of! Thanks
Just realized that may be a piece if brass and not a casting!

 

[shepherm]

@shepherm
Just curious, was there a physical problem? Or just a visual spot on the fired brass?
I have a fireform barrel with a similar ring, it doesnt cause me any issue. At least any issue Im aware of! Thanks
Just realized that may be a piece if brass and not a casting!

Yes, I had a physical flaw in my chamber. I ended up setting the chamber back almost two turns to clean it up. I too didn't see a lot of problems on the brass other than that spot. My guess and it's a complete guess, it will probably shorten your brass life over time. BTW if you're talking about the rings (lines) that go around that's from the chamber not being polished, and I'm not sure I'm as concerned about it.

 

[Shawnba67]

I meant did you look at your brass and realize you had a problem? Or did your bolt tell you you had an issue? Im just curious.

 

[shepherm]

I meant did you look at your brass and realize you had a problem? Or did your bolt tell you you had an issue? Im just curious.

Yes, I had just noticed the mark on the brass as I worked up the load. There wasn't any other issues and the gun shot great.

 

[liseo]

Dont you go to deep with pre bore operation and wrong taper? Just asking, I do the same some time ago....

 

[Danny1788]

Use a flush system. Never rolled a chip yet. I don’t have some fancy expensive setup, but it clears chips very well. I pre bore and ream the chamber at 200rpm
View attachment 1080361

Just because I’ve gotten a few PM about my pump and setup.

My pump is the cheap POS water pump from harbor freight. I just looked and they don’t sell it anymore. I did find the same 3/4hp pump on eBay though. The water filters are from Home Depot and I used the carbon filters because they are finer. I have about $300-$350 into this setup

I drill and tap my muzzles for 1/8npt threads and use a “super swivel” look it up on EBay it’s about $40-$60 it’s a high pressure rotary union for a pressure washer. I’ve used it for a few years with no issues. Don’t know how long it will last but for the price I’ll just buy a new one.