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What's your favorite way to dial in a barrel?

Yeah those polished alum inserts are great for 416.
Ok cool! Thanks for the tip
and that makes sense cuz the profile on them looks very similar to one of my larger boring bar
inserts, which so far I've seen makes the nicest finish cuts on 416
the curls just glide right off
 

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Those that Aaron listed above are specialized and best for small chambers like a PPC.
A 1/4"/6mm indexable carbide shank tool would likely serve you better for larger cartridges. Also shown are polished inserts for aluminum that work great on steel. I think this is more what Aaron was referencing he'd used in the past. @LVLAaron comments?

Exactly. I use both / all of the above. The little micro 100 bar is nice for pre-boring lands on a 5R- But the little 6mm indexable bar is what I usually use for the body of a chamber
 
Yeah that reamer was way too pricey for just a .308
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As for the pilot, I have one carbide reamer with a spiraled pilot
I imagine the reason is: being useful for using with a flush system
otherwise no need
The spiral pilot bridges the groove gap and stays on top of the lands. Kennametal has been making chamber reamers for industry for a while now.
 
There are a lot of different ways to approach chambering and virtually all can work. There are a number of factors which might influence the choice of method. Primary among these is the straightness of the barrel. Most good barrels are pretty straight; rare barrels are near perfect. I'm fitting one now, from Hugh Williamson, which is exceptionally straight, and is a treat to work with.
On my YT channel, I try to show various methods for doing things (using old, ratty, equipment and little in the way of skill) and on this one, I decided to show setting up between centers to thread and in the steady for chambering.
Now, "back in the day", it was commonplace to grab the barrel in the three jaw chuck, face it, ream a center with a piloted center reamer, grab it at the muzzle (again with the three jaw), support the breech end on the tailstock center to true the shank and cut the threads, then mount the steady rest to support the barrel for chambering. To a large extent, this was done for the sake of expedience, and it worked OK. In fact, with just a little care and a straight barrel, it was fine. And it was quick. I could complete a half dozen rifles in an eight hour day (fit, chamber, cut and crown, cut extractor cut if required, polish and bead blast).
For this Williamson barrel, I didn't take quite so cavalier of an approach, because I didn't want to compromise the job at all. So, I dialed in both ends of the barrel to ream the centers so that, on the breech the runout was zero and at the muzzle it was .0003TIR. From there, I went ahead and set up between centers to thread and true the shank, then set up in the steady to chamber. In the steady, running on the shank, runout of the bore was still zero. I roughed the chamber with a common twist drill, which drilled right on size and produced a hole with less than .0002 TIR. So, in this particular instance, this method will work about as well as any; largely because I took great pains with the centers and because the barrel is so straight. If the barrel had shown a significant amount of curvature, or if I had seen any runout at any point, I would have had to set up differently to deal with that.
My whole point is; any method CAN work, if everything is right. It's when not everything is right that you might have to adapt a little to meet the circumstances.
By the way, I'm sure I've mentioned it before but, if your tailstock center sits high, run the machine for long enough to warm the headstock up well, then check it again. WH
 
Yes. They're sharp as a cats claw and leave a great finish. Less cutting pressure than a carbide bar, which is nice when you've got a tool that's less than a quarter inch in diameter and sticking out 2.5 inches.

And the inserts are dirt cheap.
We use those on wood as well st work.
 
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which tool holder for these inserts? Boring bar, profiler, etc.? inserts just confuse the hell out of me to make sure what is compatible with what.
which tool holder for these inserts? Boring bar, profiler, etc.? inserts just confuse the hell out of me to make sure what is compatible with what.
Type in the insert on Ebay and also put boring bar in the search words and you will get the part number, So those are CCGT inserts and you get this part number for the boring bar, Change the search for tool holder and you will get tool holders for turning that use CCGT inserts.

C10K-SCLCR06​

The boring bar will have the insert numbers it uses marked on the shank.
 
Million ways to skin a cat. What has been working for me… always searching for a better way though!

1. Through headstock, 4 pt brass tipped spiders both ends… leave as little hanging out of the chuck side spider as is practical. Don’t bind and bend the barrel when indicating!

2. Rough in OD with indicators both ends… let’s say within .005-0.010

3. Pin both ends, rough in to .001-.002 both ends.

4. Leave pin in at muzzle, long stem Interapid at breech

5. Indicate grooves within 0 - .0003 (half a graduation) over 1”, 1/2” forward and behind freebore. Do this while holding muzzle pin within .003. I hate timing barrels. Capable with most quality blanks but not always.

6. Make the tenon, recheck bore before chambering just to make sure it didn’t move. Use tight fitting bushing that free slides in bore. Have grizzly rods just to test fit bushings.

For the crown I flip around and use a pin in the bore and sweep over a length to make sure it indicates the same. Makes sure the crown is square to the last part of bore guiding the bullet.

My chambers indicate within a few ten thousands when done and no discernible runout at leade.

Been meaning to try the pre boring but need it to be on a barrel of my own. Have all the tooling but been stupid busy with customer work for quite a while.

James Root
10X Engineering
 

The inserts that bar comes with, while not the ones we're talking about, are surprisingly good.
I thought the price was pretty good for that carbide boring bar until I looked on alixpress, I found 1 for NZ$24.26 plus NZ$13.56 for the CCGT060204-AK N01 and NZ$10.92 for the CCGT060202-AK N01
The US$35 boring bar works out at NZ$62.86
 
For the indexable challenged, I suggest this book. The author is very active on the hobby machinist forums and this book was a life saver when I got my machines.


You just have to remember that he has a very elitist attitude about tools. His entire reason for doing a book was to sway people from buying cheap tooling. That attitude will keep you out of trouble and you have something to brag about in the weekly bridge club but I like to explore the cheap myself.

You can learn as much from the Engineers black book

also Little Machine Shop explains it pretty well.
https://littlemachineshop.com/info/insert_charts.php

https://littlemachineshop.com/info/turning_tool_chart.php

 
You just have to remember that he has a very elitist attitude about tools. His entire reason for doing a book was to sway people from buying cheap tooling. That attitude will keep you out of trouble and you have something to brag about in the weekly bridge club but I like to explore the cheap myself.

You can learn as much from the Engineers black book

also Little Machine Shop explains it pretty well.
https://littlemachineshop.com/info/insert_charts.php

https://littlemachineshop.com/info/turning_tool_chart.php

Yeah, I don't care for the guy myself, He comes off as I'm better than you and everybody else. He has to show everybody that he has the most expensive of everything.
 

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