Home Forums Hunting & Shooting Gunsmithing Chambering reamer chatter

I need helpful suggestions, answers would be even better.

I am chambering a barrel to 280 Rem. for a friend. (his barrel and his reamer)
I put it between centers, trued the chamber end and put it in a steady rest. All went well until about .o25 from the go gage fitting and the reamer developed a chatter. I was running the lathe in back gear, 50 RPMs using a heavy cutting oil. The reamer has 6 straight flutes and is held in a floating reamer holder in the tailstock. How do I remove the chatter marks so I can finish the chamber?

If you're that close, you may not be able to get a good chamber.. Try wrapping the reamer with a layer or two of masking tape, then re-insert and cut again.. Only go about .010 before remove, re-tape and try again..

Get rid of the floating reamer holder.. IMHO, those cause more problems than they cure.. I've got one - used it about 3-4 times.. Haven't used it in 7-8 years.. If the barrel's set up properly in the headstock, you'll never need a floater..

My cure for chatter has alkways been to wrap the reamer, from front to rear, with a strip of cotton cloth. Oil liberally, then feed it in until you see some chips. If the chatter is too bad, you may not have far enough to go to clean it up; especially if there is chatter in the neck. GD

I agree with Redneck and greydog. You should speed up the rpm slightly. Check the steady rest for proper adjustment. Check the lathe for level. When I went to a heavier more rigid lathe and started chambering through the headstock all my reamer chatter problems went away.

If the barrel's end is chucked, and there is a lot of barrel sticking out, a reamer can chatter because of the barrel twisting as the reamer cuts.

That is the reason I have never liked using a steady rest for chambering.

I always try to chamber with the least amount of the barrel on the chamber end sticking out of the head stock. The more barrel, the more likely the torque and the chatter.

Unfortunately correcting the chatter at the beginning of the job is much easier than near the end. Anyway, at this point, if it were me, I would attach a lathe dog to the reamer and try hand feeding the reamer using the tail stock, with the machine off, in hopes of reducing any further damage by the transmission of vibrations through the machine and reamer.

Wrap the reamer in waxed paper and feed it in. You will probably have to go deeper but that is not a problem usually. Don't ask me how it works, it does. Speed up the lathe also, I have found that too slow can cause problems like that.

Malm
I agree trying it by hand at this stage may work.

Jkob
When you try the wax paper, instead of cutting oil use Crisco or lard.

Never had a problem using cutting oil, it works.

I haven't chambered many barrel but i have never had chatter when cambering at a speed of 115 and using a good cutting oil .

Don't want to put a hex on you, but there are two types of people who chamber barrels, those who have experienced chatter, and those who are going to.

As far as floating chamber reamer holders go, I used to be in the same camp as Redneck, but then I tried a PT&G "Bald Eagle" and have been using it ever since. As long as I pre bore the hole using a boring bar and not a drill bit, it works fantastic! I've never tried reaming from scratch with one, have always removed the majority of material with a boring bar first. Faster, and with less wear and tear on the tooling. As long as the lead angle on the shoulder portion of my reamer is correct and not too steep or aggressive, I've never experienced chatter using it, which ties this nicely to the topic of this thread.

Wow,talk about good information. I appreciate all the responses I got. I am constantly amazed at the knowledge of the "Fire" members.

During the time since my post and as I was reading the replys, I decided that first I will pull the barrel out of the lathe, I will clean the chamber and bore and make a chamber cast with Cerrosafe. That should show me all the places there is chatter. After doing that I can decide if I need to go deeper, face off the breach and the shoulder or if something else will work. Thanks so much for your input and help.

I appreciated Malm's response. Prior to this barrel I too had never had to deal with chatter. But then it happens and you are not ready and don't know what to do.

You will the first time you chamber a .300 H&H...

I couldn't agree more..

One of the worse things you can do is remove the barrel midway through the job. I once had my lathe tied up for over 2 weeks waiting for a custom reamer to replace the one that broke having rolled off the bench and hitting the cement floor. It is easy to clean and eyeball the chamber using a good strong light.

You can probe the chamber with a tooth pick if you want to feel for the presence of the chatter. But at this point, I would continue pressing forward, cautiously, until the problem was either resolved or at a stalemate. If it were resolved, then you could make the necessary adjustments to the breech end of the barrel and go on with the job. Or, seek further help.

One other thing you can try first, try polishing the chamber to see if you can remove the bulk of the chatter and then proceed forward slowly. Good luck!

You got THAT right.. Yep.

It doesn't bother me in the least to remove and replace a barrel. If I set it up once, I can set it up again! Still, I don't make a habit of it.
I have had reamers which have treated me well for a dozen chambers suddenly start to chatter on the thirteenth then never do it again. My conclusion is that I've gotten a barrel of slightly different composition. I'll bet I chambered a couple hundred barrels before I had a reamer chatter. At that time I was so cocky that I was shocked that this could happen to ME! That was twenty years ago and now, I'm pretty used to it. Now I kind of think, the older I get and the more I do, the less I know! GD

When I was learning how to chamber 10 years ago, I got information from:
1) Mike Bryant's site
http://www.bryantcustom.com/articles/rebarrel.htm
2) A Staff gunsmith at brownells who told me I didn't need a rougher and how to do the arithmetic to know when the chamber is deep enough.
3) Ed Shilen's drill, boring bar, reamer technique I have added doing that in stages, so the pilot is always engaged.
4) Roy Bertalleto in Feb 2000 posted a picture for me of a lathe spider on yahoo gunsmith
http://public.fotki.com/Rbertalotto/machine_tool/shop-pictures/p1010005.html
http://sports.groups.yahoo.com/group/Gunsmithing/message/818
5) At the Puyallup gunshow in 2003, Brett Evans (a gunsmith and benchrest competitor), said I need to put a piece of copper wire [gimbal] around the barrel in the 4 jaw so the spider makes the barrel pivot and not just bend.
6) Daniel Cowen of Renton says he uses a Bushnell collimator bore sighter spud to dial in the spider in a steady rest, when a pin gauge will not reach, because there is already a chamber there.
7) Randy Ketchum of Lynnwood Guns and Ammo, told me he grinds a spud on the tool post grinder to within .0002" of the bore, so he use two test indicators on the spud to dial in the barrel near the chamber. He said all barrels are bent with a spine and just pay attention to the bore near the chamber. He said he pushed the reamer with the tailstock and countered the torque with a tap handle in a piece of shotgun barrel. The shotgun barrel runs stiffly along the ways, so it does not chatter, but he lifts the barrel off the ways with his finger to feel the torque is not too much. He pulls the reamer out every ~ .050", scrubs the reamer off in gas mixed with oil, slathers the reamer with cutting oil, and puts it back in.

What does it all mean?
The short steel rod or tube from the wrench on the reamer to the ways is so stiff, it that were the floppiest part of an oscillation loop, the chatter might be too high frequency to hear.