Reaming Carbide Sizer Die?

B

black mamba

New member
I have an S&W Model 25-5 with a pinned barrel that has large chambers. Fired cases measure .481-.482 with 13k loads. A .454 diameter bullet will easily go through all 6 of the chamber throats. I'm getting split cases from just a few firings, because my sizing die takes them down to .472 at the base.

Is it possible to ream a carbide die to larger diameter? If it would only size to .477-.478, then they wouldn't expand so violently into the large chambers. What other solutions can I try? Thanks in advance!
 
Opening a carbide sizer

Cannot be ream3d, but can be honed bay a machine shop with a diamond hone for machining carbide.
Good luck!
 
I would explain your situation to the die manufacturer. The only thing that's harder than carbide that can machine carbide is diamond.
 
S&W would prolly make a new cylinder since yours is out of spec. Take advantage of the lifetime warranty and make it standard size chambers. It would save you a lot of problems in the long term.
 
I would explain your situation to the die manufacturer. The only thing that's harder than carbide that can machine carbide is diamond.
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As I remember when in machining classes in college we would sharpen Tungstan Carbide inserts that were brazed onto lathe tools using a Green Silicon Carbide wheel.
 
dahermit said:
As I remember when in machining classes in college we would sharpen Tungstan Carbide inserts that were brazed onto lathe tools using a Green Silicon Carbide wheel.
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That's to resharpen an insert that's already been softened through machining processes and you're just putting an edge on. This is to leave a smooth finish and then for diamond lapping.
 
That's to resharpen an insert that's already been softened through machining processes and you're just putting an edge on. This is to leave a smooth finish and then for diamond lapping.
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I did not realize that a used tungsten carbide cutter became soft from being used...must have missed that day in class.
What "machining processes" soften tungsten carbide cutter bits? That sounds like something that would be good to know.
 
I've sharpened carbide tools on the "green wheel" but the embedded material wasn't carbide, I believe it was industrial diamond dust. IIRC the wheel were very expensive...
 
I've sharpened carbide tools on the "green wheel" but the embedded material wasn't carbide, I believe it was industrial diamond dust. IIRC the wheel were very expensive...
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"Green Wheels" are Silicon Carbide. Here is the description for on currently on sale at Ebay.

Green Silicon Carbide Abrasive 6" Grinding Wheel 60 Grit

Condition: New,

Item Description:

This auction is for (1) Masonry Green Silicon Carbide Abrasive 6" Grinding Wheel 60 Grit.

For Sharpening Carbide tool bits and other carbide applications. You can use them on hard stone. They are cool cutting and provide an excellent finish.

RPM: 3600
6" x 1" x 1"
Grit GC60 - 1
Starting Bid: $27.50
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On the other hand, this is a diamond wheel...notice it is not "Green".
https://www.sharpeningsupplies.com/Diamond-800-Grit-Wheel-for-Model-327-P1179.aspx
 
There is a good chance if you sent that die back to the maker they could adjust it for you.

You will have to explain what is needed so the maker knows what to do.

The best way to fix the problem is as said earlier - send the gun to S&W and have a new cylinder fitted.
 
The 25-5 throats you have are meant to accommodate the old 0.454" diameter .45 Colt bullets. Today most cylinders are all made for 0.451 bullets, AFAIK, so your modern carbide resizing die is trying to make the cases small enough to hang onto those narrower bullets. But if you have a cylinder for the old bullets, it will be wider. The SAAMI standard allows a 45 Colt chamber throat to be anywhere from 0.452" to 0.4595" diameter, so I doubt you are out of spec. If you slug your chamber throats or even borrow a set of pin gages to determine their diameter and get bullets from equal diameter to 0.001" smaller, you will get the best accuracy, no matter how much squeezing down the forcing cone has to do to get them into the bore.

I believe Lee will make you what you need by custom order. This is better than grinding the die out for yourself as they have a specific elliptical profile they use and they polish it so it doesn't scratch the brass. But before you do that, make the chamber measurements and find your bullets so you can send them a couple of the bullets and fired cases to let them determine what diameter to make the sizing ring. I believe Redding will customize dies as well. You will have to call these guys for prices.
 
What will also help is using softer bullets.
Use a 1-20 or softer bullet so it will upset and fill the chamber throat. And the best is a custom die.
 
Try resizing the brass with Lee Carbide Factory crimp die without the crimp ring.
Then resize the upper part of the brass where the bullet seats with the regular sizing die.
 
dahermit said:
I did not realize that a used tungsten carbide cutter became soft from being used...must have missed that day in class.
What "machining processes" soften tungsten carbide cutter bits? That sounds like something that would be good to know.
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I was thinking of HSS, my bad. Yeah, carbide doesn't get soft.

Got my cutting tools mixed up.
 
I was thinking of HSS, my bad. Yeah, carbide doesn't get soft.
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Close, but no cigar. HSS steel bits will get soft when at Red heat, but will harden again as they cool...they are made from Air Hardening Steel. Tool Steel, on the other hand, becomes soft when heated and stays soft when cool (annealed). Luckily, Tool steel cutters have become mostly obsolete and are not encountered frequently anymore. I did run into some in a Middle School woodshop several years ago with the wood lathes. It was a challenge to sharpen them without getting them too hot and wrecking them.
 
Well, guess what? I find that I am back into the 'only one' category. I have rock sharpeners, I can grind the diameter, angles or I can grind the length. If I was grinding a die with straight walls with an insert I would not grind the length of the rock because the rock will reduce in diameter as it is used.

And then there are tappers, use coolant, most would be surprised at the finish, I am not the fan of the cross hatch.

F. Guffey
 
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