I have a 7x57 that I'm considering changing to the improved version. My question is--can the sizer die be reamed with the improved reamer so I wouldn't have to buy a new die set? Or would it be better to just spring for a new set? For that matter, will the improved reamer clean up the 7x57 chamber? Thanks!

It will ont work. Dies are very hard (on the surface) and your reamer would be trashed before you removed enough materail to do any good.

ACRecurve---

There's two reasons it won't work..... First, the die is harder than Chinese arithmetic and a reamer won't cut it, the second is that the reamer that cuts a resizing die is smaller than the chambering reamer.

The AI reamer will clean up the old chamber but the barrel MUST be set back to properly headspace the new cartridge.

Right on all counts in the above posts.

Buy a AI die set from Redding, RCBS, CH4D, or one of the other makers.

I sometimes make die sets for the big bore rifles I build, but in addition to the finish reamer for making a seat die, it takes a resize reamer to make the size die. Ream the dies, then heat treat, then polish.

A resize reamer cost about $150, throw in the labor for making the dies, and you are far above the cost of a die set from one of the reloading die makers.

It's like John sez. Dies for the AI series of cartridges are relatively cheap.
It is possible to anneal a die, ream, then reharden but it would not be any advantage. This is something gunsmiths used to do 50 years ago before they knew better! Regards, Bill.

Thanks for the replies...that's kinda what I thought I would get but thought it was worth asking...guess my cheap side was peeking out! It is nice to be able to ask a question and be answered by experts! Thanks again.

Good Hunting,

Some years ago I noticed my wife using her self-cleaning oven. Something like 700 degrees and a three hour cycle and another 3 hours to cool down so you can open the door.

Put in a set of Hornady and RCBS dies. Crossed my fingers while reaming. Worked fine with no damage to reamer and dies are still in use after several hundred rounds.

This will not make a FL resizer (only a bump die) and the neck sizer must be modified to take proper size bushing.

Since then I have done this for 260 Remington and 250-3000.

Wally

Chambering reamers are expensive. Don't try it. Try Redding. They may have what you want for a reasonable price. Ch-4D dies are good, but it took them 7 months before I got my 6.5-06 AI dies made.

Like JBelk said, Harder than a Chinese arithmetic. Now you can purchase die bodies from NEWLON Precision 209-966-8141. You can chamber these diebodies and they use a S type bushing like Redding has. The die bodies are not hardened. Made for neck sizing.

Redding has a set in Midway USA for $58 dollars.

No. Dies are heat treated for a reason. Only to deal with moving brass though.
wallyw, no home oven goes to 700F and that isn't hot enough to do anything anyway. If steel doesn't get red hot, nothing happens. A self cleaning oven is to burn organic substances into carbon. Just like cranking the barby to high for the forst 5 minutes, so you can brush off last night's dinner.

"If steel doesn't get red hot, nothing happens."

This is totally wrong. Steels generally start losing hardness by 400 degrees F.

Actually you can draw the hardness out of good knife steel at 375 degrees, look for straw yellow to light blue depending.

Dies are hardened to reduce the coeffecient of friction. Harder means slicker.
Dies are used "as quenched". That means the hardness will begin to leave at about 350F and will become fully annealed at about 1400F. The hotter the die becomes the softer the steel will be tempered, or drawn back, in hardness.

The fact remains that the chambering reamer is made for chambers and sizing reamers are made for resizing dies. They don't mix.