chambering reamer chatter marks fix

coyote

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cut a chamber the other day with a new 223 reamer and when I noticed chatter marks in the chamber it was to late to rescue it being about 80 thous from headspace.I finished it in almost one quick pass to load up the reamer and it helped it a bit so I sanded it a bit and tried it.
It left some small ridges along the fired brass nothing serious it grouped well but bugged the crap out of me seeing it was my son's first centerfire so I pulled the barrel back off.

Today I put it back in the lathe cut about 50 thous off the shoulder and redid it by pocking a small hole through a small patch placing it over the pilot of the reamer saturating it with oil and going in rather quickly it did an amazing job the chamber is nice and round like it should be.

I have tried in the past loading up the reamer to prevent chatter and the wax paper method but this is by far the best method I have tried .
this reamer is off to the maker this is the second chamber cut with it with the same results both times.
 
chambers should be cut with AMPLE amounts of cutting oil, preferably with the oil coming through the muzzle and exiting out of the flutes of the reamer, bringing chips with it. If you do not have through oil, you should be making small pecks of .050-.100 and flushing the hole with a squirt oiler or something. Before finishing the chamber, you should stone the face and edges of the reamer to remove any built up edge. You should be able to use ad re-use the reamer hundreds of times without having to send it back to anyone with this method. You also have to set your RPM properly. 120rpm is a good speed.
 
If it is a fixed pilot reamer have the toolmaker re-grind it for a floating pilot. It's well worth the $30 extra. Fixed pilots tend to be on the small side so they will fit in any barrel. I have found that when I have had chatter that the pilot/bore clearance was less than ideal. In fact I don't recall ever having chatter with a close fitting pilot.
 
I go no more than 0,035 / pass. Time consuming, but its just a hobby, I only do my own.
I hold the holder handle with 2 fingers and if I feel it bite too much, I put a cleaning patch on. I use ridgid thread cutting oil and a lot of it.
 
Wrapping the reamer with cloth is a tried and true,old-timey, technique. Filling the flutes of the reamer with plasticene is also quite effective as is wheel bearing grease. When a reamer has a tendency to chatter, it may be due to in adequate stagger of the flutes or having cutting edges to close to center. Excessive clearance or too fine a margin are other possible culprits as iare speed and feed. I have more Clymer reamers chatter than any other and the cloth wrapping technique came from Max Clymer by way of Gunther Kautsky. I don't recall who told me about the Plasticene but rest assured I didn't think of it on my own ( I lack the mental acuity). The grease, I tried because I didn't have any plasticene. I don't know how many hundreds of chambers I have cut but now and then, I still run into an issue. I had one Clymer reamer which was almost gauranteed to chatter and I cursed it every time I used it. Finally, it grabbed and broke one tooth right out. I rounded off the corners of the break at the edge and finished the chamber. The reamer never chattered again and produced good work for some time until I replaced it with a JGS because it bugged me to look at it. I have been tempted to try grinding off one edge on some of the other chatter-masters but have not been able to bring myself to do it.
 
Leeper I read about the cloth just a few days ago on a forum and figured I would try it wish I would have known about this method a long time ago ,tried cup grease a few times but only when it just starts up will be using the cloth patch from now on.
 
I found a good method that worked better for me than the patch method. I believe it was Rod Henrikson that posted it over at practical machinist. You put the reamer in the barrel, then put a dead Center in the tail stock put light pressure on the reamer then turn the reamer by hand with a wrench feeding about half to one thou per revolution. Took about .030 to clean up the chatter but it worked excellent for me.
 
I use paper towel and wrap the reamer. This has always worked for me.
Chatter is nothing. Wait 'til you fight BUE
 
Ok now I'm really curious Rob what the heck is BUE lol I just can't figure it out :redface:

edit: Just figured it out built up edge I fight this all the time with the gundrills
 
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I have been very impressed with PT&G reamers. Start with the rough reamer and then use their finish reamer. No chatter at all. I do the finish reaming by hand. And the reamers are piloted.

Using synthetic 15-40 oil and cleaning the reamer and chamber frequently helps. Reamers are not drill bits and lack the ability to auger chips out of the way.
 
My last BUE battle was miserable and I would sum it up as my loss due to the torment even though in the end the chamber was fine. I used the same reamer again later and it was the easiest chamber job I have ever done. I mark the root cause of my earlier frustrations up to the barrel steel properties since that was the only change.

This should strike fear into those blissfully ignorant. If your happy, don't click.
 
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