• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Chamber problems

I have a question about chatter in a chamber while running the reamer in--Can this be caused by a tight pilot on the reamer
Bore scope the bore. If it's scarred-up the pilot is too tight.
Spindle speed might be off, too. Perhaps too fast. What speed are you using?
 
Chatter can be caused by a number of things, but a tight pilot isn't one of them. Potential cause include:
a. Loose bearings on the lathe.
b. Instability or flex in the holder/driver.
c. Improper (excessive) clearance angles on the reamer and
d. Improper reamer geometry.
Of these causes, I think (b) and (d) are the most common.
As Butch mentioned, wax paper can help (best used before chatter gets too bad). Wrapping the reamer in cloth, filling the flutes with Plasticene, or filling the flutes with a heavy grease, are also viable cures. WH
 
As mentioned, The wax paper trick works almost every time. Sometimes increasing speed and pressure will get you out of it, But do the wax paper, It works. Dave Tooley also says use wax paper.
 
Pretend your reamer is a cleaning jag, and you're putting patches on it. Spear a few patches of waxed paper onto the neck section of the reamer, so that they lay back along the body.
And firm pressure. A fully engaged reamer has lots of cutting edge length in contact with steel.
 
I wrap the body of the reamer with one full turn of wax paper. In extreme cases it may take more than one application but it has never failed to eventually stop the chatter. I have a couple of problem reamers that I know will cause a problem. I keep cut to size paper with other odds and ends handy.
 
I recently bought my first replacement barrel for a customer, carbon of course. I dropped a 6 Creedmoor reamer and rolled an edge, I stoned it, ran it in for two passes and that rolled edge caused chatter. So I stopped and ordered another reamer. I got the new reamer and it never didn’t chatter. I tried a patch, wax paper, sped up/sped down, increase feed, decrease feed and nothing worked. The new reamer chattered the entire way and I got within .200 of headspace and phoned a friend. He’s a machinist and accomplished gunsmith…we tried everything and never got it out, he even cut it all out of the shoulder with a boring bar and then as a last ditch was to even put it in my Jacob’s chuck.

Few things I learned…while the JGS reamer holder is awesome, once you have chatter the design of it does no favors in helping you stop it. I have one that my buddy gave me to try but I will eventually find a design that works off a center or pusher type design. Even new reamers aren’t perfect, turns out there is something wrong with the new reamer.

One of those jobs where you spend $1200 to get $400 and questions your entire reason for doing this stuff. :rolleyes:

Good luck, it’s frustrating!
 
while the JGS reamer holder is awesome, once you have chatter the design of it does no favors in helping you stop it.

Agreed on that. As a part of my drill/pre-bore I've been cutting the shoulder angle in the barrel, and starting the reamer with a "little more than normal" feed pressure. Seems to help.

I picked up a PTG floating holder from a member here... I haven't used it yet, but want to test it out when things slow down. It has a collar that you can adjust how freely the reamer floats.
 
I have a 7 PRC reamer that loves to chatter. I made it through the first barrel ok. Second barrel same issue. I ran it on my other lathe and cut two mock chambers. It still chattered on the barrel. I had a 28 Nosler barrel to do next. I ran my 28 Nosler reamer in that same barrel, it went with no chatter. Next barrel was the same, fought it all the way, even ran it on my 17” Kingston rather than my 14” machine just to see. New reamer is on the way!
 
Chatter can be caused by a number of things, but a tight pilot isn't one of them. Potential cause include:
a. Loose bearings on the lathe.
b. Instability or flex in the holder/driver.
c. Improper (excessive) clearance angles on the reamer and
d. Improper reamer geometry.
Of these causes, I think (b) and (d) are the most common.
As Butch mentioned, wax paper can help (best used before chatter gets too bad). Wrapping the reamer in cloth, filling the flutes with Plasticene, or filling the flutes with a heavy grease, are also viable cures. WH
I agree with Will Henry , I'm not a machinest but did chamber some barrels for me . I rented a reamer that chattered so I had a reamer made and never had any chatter . as Will said B & D is the most common .
 
Agreed on that. As a part of my drill/pre-bore I've been cutting the shoulder angle in the barrel, and starting the reamer with a "little more than normal" feed pressure. Seems to help.

I picked up a PTG floating holder from a member here... I haven't used it yet, but want to test it out when things slow down. It has a collar that you can adjust how freely the reamer floats.
I use the PTG floating holder. I’ve only chambered a few barrels thus far, but it’s worked very well. The first three were with a (new at the time) 6Creed Manson HS reamer. The next one (action due Feb) will be with a new JGS HS in 6BRA. Will chatter bite me if its first use is on my barrel blank? I will find out…..
 
You'll be alright. My own two cents here, and free advice is worth what you pay. Manson reamers are REALLY sharp. They leave a nicer finish after they've been used once. Honing the edge with a copper penny would probably have the same effect.

For the record I'm not saying anything bad about Manson. I buy a lot of their tools/reamers.
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
165,786
Messages
2,203,175
Members
79,110
Latest member
miles813
Back
Top