PDA

View Full Version : resizing die



johan teughels
11-18-2015, 12:31 AM
made my own resizing die with a rezizing reamer
polished and then ultrasonic cleaned the die but i still have scratches on the brass
the die is not hardend (yet)
how do i get those marks out ?

r44astro
11-18-2015, 05:58 AM
My sizing die was made same way with Newlon blank. I used a chamber mop with lapping compound, started with 200 and finished with 600 spun it in the lathe. My die is not hardened, works great there are a few scratches left but nothing that has caused me a problem.
Bill

Dusty Stevens
11-18-2015, 08:24 AM
The die must be hardened to stop the scratches

Tim Singleton
11-18-2015, 08:34 AM
Are the scratches just superficial? Is it enough to care about? In other words do they effect how it shoots?

F. Guffey
11-18-2015, 09:36 AM
made my own resizing die with a rezizing reamer

Then there is that part about scratches. I have 65 chamber reamers, I use them to cut chambers. When I finish reaming a chamber it is as smooth as glass. I like that in a chamber, 100% contact is better than anything less. Then there is that part about cutting dies with a chamber reamer and the commercial aspect.

Back to cutting a smooth chamber, if my reamers cut a smooth chamber in a barrel the same reamer will cut a smooth chamber in a die blank. Then there is the belief the die chamber is smaller than the chamber. Next comes lapping/polishing the inside of the die, back to the part where the die chamber is smaller than the barrel chamber. Lapping/polishing involves stock removal, so if the die chamber is lapped/polished to remove the scratches and the chamber in the barrel is the same size as the chamber in the new cut die: I ask, after polishing isn't the die chamber bigger than the barrel chamber?

Then comes the neck in the die, if the neck is cut with the same reamer isn't the neck in the die too large in diameter?

F. Guffey

mwezell
11-18-2015, 10:21 AM
Harden the die, if hardenable material.

Wilbur
11-23-2015, 06:35 AM
Are the scratches just superficial? Is it enough to care about? In other words do they effect how it shoots?

Tim - From years and years of experience I can say that you've wasted some words here. Never mind that the die might be perfectly fine - it scratches! :)

Greg Walley
11-23-2015, 09:59 AM
A proper full-length sizing die must be heat treated, or gas or salt-bath nitrided. A soft die will continually gall and tear material off of the brass. If it's a 416 stainless steel blank from Newlon Precision, it can be vacuum heat treated to about 40 Rc.

Greg Walley
Kelbly's Inc.

DSM
11-23-2015, 09:10 PM
Where can one get a SS die melonited or hardened? I made a PPC ring die from a piece of SS barrel. It's polished and scratches the brass some.

Dusty Stevens
11-23-2015, 11:27 PM
They have a minimum charge which makes it very much not worth it unless you have a big pile. Id go to a local machine shop and see if they can throw it in a batch for you

Wayne Shaw
11-24-2015, 06:13 AM
I have used Fireball Heat Treating in the past. No problems.

johan teughels
11-24-2015, 12:31 PM
A proper full-length sizing die must be heat treated, or gas or salt-bath nitrided. A soft die will continually gall and tear material off of the brass. If it's a 416 stainless steel blank from Newlon Precision, it can be vacuum heat treated to about 40 Rc.

Greg Walley
Kelbly's Inc.


made my own from an old krieger barrel so it is probably 416R