Inside neck chamfer with oxide cones

[Just Dave]

Awhile back, I saw on here that somebody was using alum-oxide cones to chamfer the inside of the case neck instead of cutting with standard metal tools to produce a smoother cut.

I've searched all over, and cannot find anywhere that sells them in less than 100-lot pricing, or if they sell the cone separate from the mandrel, you have to buy 10 mandrels min @ $7 each.
.
Just want to try this without investing a small fortune,, anybody got a source ?

 

[KMart]

Awhile back, I saw on here that somebody was using alum-oxide cones to chamfer the inside of the case neck instead of cutting with standard metal tools to produce a smoother cut.

I've searched all over, and cannot find anywhere that sells them in less than 100-lot pricing, or if they sell the cone separate from the mandrel, you have to buy 10 mandrels min @ $7 each.
.
Just want to try this without investing a small fortune,, anybody got a source ?

New
See if one of these might work. Maybe a number 14 with a 120 grit. you would need to figure out a handle.

https://www.mcmaster.com/#grinding-bits/=1bdww2r

 

[Mikemci]

Dremel tool accessories, probably has them. Check Home Depot or Lowes.

 

[Just Dave]

New
See if one of these might work. Maybe a number 14 with a 120 grit. you would need to figure out a handle.

https://www.mcmaster.com/#grinding-bits/=1bdww2r

Thanks! That's getting me closer. I might try one of those. Trying to find one long enough, with a fine point, so the angle is right, too many of them are almost 45degrees.

 

[Just Dave]

Dremel tool accessories, probably has them. Check Home Depot or Lowes.

Tried that but they're all too coarse, and real steep angle

 

[ireload2]

No one in the metal cutting world uses a ceramic to cut a soft metal. The brass will just load the ceramic. Use a counter sink with one or 3 flutes that is running at low rpms. Say somewhere between 50 and 200 rpm. If you go too fast you will get chatter and a crummy finish. If you are all about speed you will only get a crummy finish.

 

[smoooth]

https://www.travers.com/zero-flute-...-tools/p/101685/?lite=true&pricelistname=SITE

https://www.travers.com/zero-flute-...g-tools/p/82722/?lite=true&pricelistname=SITE

 

[Paddyd]

You risk getting abrasive grit embedded in the brass, which may or may not transfer to the bullet jackets.. Personally, I think I'd rather not risk gouging up my shiny bore.

 

[mikeeg02]

https://www.midwayusa.com/product/949365/lyman-carbide-chamfer-tool-vld-very-low-drag

My one of these has quite a few flutes. And is very, very sharp. I put it in my rcbs prep center. Does a very nice job. I can't imagine asking for anything better.

 

[ireload2]

The more flutes you have the slower the tool needs to run to avoid chatter.
There are even designs by Severance Tools and KEO that are called zero flute designs. They are nearly impossible to make chatter. Industrial quality countersinks are very highly developed cutting tools since they are used to deburr billions and maybe trillions of holes each year. One product design I worked on had about 1100 Helicoils and Keenserts plus about that many through holes. We made thousands of that machine and thousands of other similar models every year. Probably more than 100 million holes and everyone had to be deburred. All done with off the shelf high speed steel countersinks.

https://www.midwayusa.com/product/949365/lyman-carbide-chamfer-tool-vld-very-low-drag

My one of these has quite a few flutes. And is very, very sharp. I put it in my rcbs prep center. Does a very nice job. I can't imagine asking for anything better.

 

[mikeeg02]

The rcbs prep center turns awfully slow. May be why the combination works so well. Not saying there isn't a better solution. But it sure is an easy and working one.

 

[mr45man]

As mentioned earlier ,i would not want any abrasive near my brass/ barrel .

 

[Brians356]

As mentioned earlier ,i would not want any abrasive near my brass/ barrel .

Lapping compound is abrasive. J-B Bore Paste and Corbin Bore Cleaner are abrasive. How far away is far enough?
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[mr45man]

Lapping compound is abrasive. J-B Bore Paste and Corbin Bore Cleaner are abrasive. How far away is far enough?
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Ammonia is all you need.

 

[Brians356]

Ammonia is all you need.

Really? Ammonia, period. Good to know, thanks!
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[Just Dave]

You risk getting abrasive grit embedded in the brass, which may or may not transfer to the bullet jackets.. Personally, I think I'd rather not risk gouging up my shiny bore.

My final prep stages eliminate any chance of material left inside case neck. They all get wire brushed, rinsed , then swabbed with HBN.. But that's an angle I hadn't considered. I will have to conduct some experiments now, and observe surface under magnification.

 

[Just Dave]

https://www.midwayusa.com/product/949365/lyman-carbide-chamfer-tool-vld-very-low-drag

My one of these has quite a few flutes. And is very, very sharp. I put it in my rcbs prep center. Does a very nice job. I can't imagine asking for anything better.

I also use that one currently,, does a pretty good job, but it depends on how straight you can hold it

 

[R.Morehouse]

The Sinclair VLD cutter is really nice. Give it a look before you decide........I always hit my freshly cut necks with some steel wool to smooth things out a bit. I'm not sure i would want a super shinny smooth piece of brass hanging on to the bullet. I leave carbon in the neck for the same reason,,,,,

Regards
Rick