- Joined
- Apr 12, 2013
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- 562
The only difference in my setup and that one is that I run my steady just in front of the threads, not on them.
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Botched chamber reaming
- Thread starter cdhknives
- Start date
- Joined
- Apr 12, 2013
- Messages
- 562
LOL. With the price and availability of 6.5PRC brass and the reduction in brass life from chamber flutes!?!?!?You could do like H&K and just call it a feature.
Fluted chamber lends to more reliable extraction!
Okay, just spitballin'... I'll shaddup now....
I have the steady rest fairly tight and am driving the reamer directly from a dead center in the tailstock. Nothing flopping around now...just don't know how well aligned everything is. I got it lined up as best I can...
How are you driving a reamer from a dead center. I’m sure I’m missing something. Can you post a photo of your setup.
Chuck
- Joined
- Apr 23, 2018
- Messages
- 6,519
@cdhknives, if there's any material left to work with, I would bore or drill the chamber to remove the grooves so the reamer doesn't follow the wavy pattern as you go. If that isn't possible, then check everything twice with a DTI after you've cut to be sure it's good. I also think the steady should remain tight and fixed during chambering. If you want to free it and let the pilot guide the reamer, then only float the last little bit, maybe?
- Joined
- Apr 12, 2013
- Messages
- 562
I was turning at 45 RPM. My time is free-ish!
I don't think I have enough metal left to cut at the shoulder to run a parallel cutter (boring bar, drill bit) down the full length...only about .005" left in diameter due to the minimal taper of this cartridge. Maybe I should change to a 6.5WSM, that would clean up this chamber!
Jubil, there was a post earlier with a link to a thread at practical machinist. My procedure is basically identical. The tip of the dead center fits the center dimple at the back of the reamer to hold it on center, and a wrench (with set screw to hold reamer) on the flats prevents rotation. Advance the tailstock to advance the reamer. Hold the wrench in your left hand (to control, aim, and withdraw), advance the tailstock with your right. It is slow going, pecking at it, especially once the tailstock runs out of travel. Then I have to unlock and withdraw the entire tailstock each cycle.
Pontiac, I tried locking down the steady last night and made a few light (about .020" advance per cut/withdraw/clean/lube/restart cycle) cuts. At first it looked promising (based on layout dye removal at the peaks, not valleys) but the last 2 were not. I am thinking about some very light cuts, extremely tedious as it will be. I guess a slightly misaligned chamber is the least of my worries now.
I don't think I have enough metal left to cut at the shoulder to run a parallel cutter (boring bar, drill bit) down the full length...only about .005" left in diameter due to the minimal taper of this cartridge. Maybe I should change to a 6.5WSM, that would clean up this chamber!
Jubil, there was a post earlier with a link to a thread at practical machinist. My procedure is basically identical. The tip of the dead center fits the center dimple at the back of the reamer to hold it on center, and a wrench (with set screw to hold reamer) on the flats prevents rotation. Advance the tailstock to advance the reamer. Hold the wrench in your left hand (to control, aim, and withdraw), advance the tailstock with your right. It is slow going, pecking at it, especially once the tailstock runs out of travel. Then I have to unlock and withdraw the entire tailstock each cycle.
Pontiac, I tried locking down the steady last night and made a few light (about .020" advance per cut/withdraw/clean/lube/restart cycle) cuts. At first it looked promising (based on layout dye removal at the peaks, not valleys) but the last 2 were not. I am thinking about some very light cuts, extremely tedious as it will be. I guess a slightly misaligned chamber is the least of my worries now.
- Joined
- Feb 20, 2019
- Messages
- 335
That posts on PM looks like he was using thru bore cutting oil, turned center, rigid reamer holder. When the reamer is held rigidly then it provides the support at the chamber end. If your tailstock is absolutely perfectly centered then that would work. I don't think your setup was the same thing.
With that method, if the tailstock is off center, then while the bushing might follow the bore, the rear of the reamer is going to be cutting oversized.
With that method, if the tailstock is off center, then while the bushing might follow the bore, the rear of the reamer is going to be cutting oversized.
- Joined
- Apr 12, 2013
- Messages
- 562
You are correct, I didn't even look at his reamer holding. I was looking at the barrel holding setup. I am on my 3rd reamer holding setup...back to past success, eliminating the floating holder. The tailstock center pusher with anti-rotation wrench is outlined in the Hinnant manual. I was unable to find a good picture online and am at work, will have to address tonight.