Have you ever polished the inside of a sizing die?

[Paul in Nevada]

I am wondering if anyone has any tips for polishing the inside of steel dies.
I bought a set of the RCBS "small base" AR dies for 223/5.56.
It seemed like it took a lot of force to resize once fired 223 brass. I also noticed the die was scratching the heck out of the cases, which left bright streaks of brass inside the die. There is one spot that always left a particularly nasty gouge. Well, after about 50 cases I managed to tear the rim off one and it got stuck (glad I decided to try these dies out on the Rock Chucker and not the 750). I busted the decapper hammering it out. The decapper is cheap on Midway but I am thinking the inside of the die needs to be polished.

For reference, I cleaned the die before first use and lubed it lightly with One-Shot. Cases were lubed with One-Shot as well. The same cases were very easy to size after I switched to a Lee die.

Is polishing worthwhile or should I ask RCBS about a warranty repair? They have been very good to me in the past but who knows what the turn around time would be at this time of year.

 

[SMSgt]

For one, nearly all the .223/5.56 brass I acquire is federal agency/mil brass. I have never found the need for small base dies. I use regular RCBS .223 dies only. I'll fully (Die touching shell holder) resize the first time and then measure the case head space length after the first firing in my rifle(s) and adjust my resizing die with shims to get a .002-.003 shoulder bump after that. Never have a chambering issue in either bolt actions or ARs.

If I felt the need to polish a die, I'd rub Filiz (sp?) polishing compound on a bore mob and run it in a drill to polish the inside of the die. The only times I've stuck a case in a die it was due to lack of lube on the lower end of the body, not the neck or shoulder area.

One Shot is prone to sticking if not allowed to dry. I recommend Imperial case lube wax. A small tin lasts a long time. It takes very little.

 

[dwh]

I had the exact same thing happened to my small base die. I contacted RCBS they said to send it into service department with 2 cases showing the scratches. They would try to polish them out and if the couldn’t they’d replace the die free of charge. I still haven’t sent it in yet.

 

[H Richard]

I hope you were using proper lube on all the cases. Keep in mind the "small base" is actually squeezing the case down further than it may have originally been. It will take a lot of force to do it. I recommend Imperial Sizing Wax.
If your dies are scratched RCBS will polish out. They have outstanding customer service.

 

[cmj8591]

It sounds like that one slipped out of the factory on a Friday afternoon. Box it up and send it back. You'll spend more time trying to fix it than it takes to ship it and you might end up sizing 45-70's by the time you're done with it.

 

[STORMINORMAN]

I've had good results using the Hornady UNIQUE (vs. One Shot) sizing paste. A little on your fingers goes a long way. Depending on the caliber 5-6 cases is not unusual with just a tiny bit on my forefinger...

Cheers!

P.S. I "polished" a 300 Blackout sizing die just yesterday: dropped some powder in it accidently. No big deal. Clean, polish, clean again & lube.


A CORRECTION NOTE: Please make that "Hornady UNIQUE" (white) vs. their One Shot (brown) wax product. I did not realize they actually have FOUR different products!

 

[Imissedagain]

The only 223/5.56 dies that were in stock, back in the late '70s at Tamiami, were small base RCBS.
Never any issues and they're cleaned after each use.
Unique lube applied sparingly with a fresh clean cloth or fingers.

We neck size bolt/single shots after firing in a Lee Zero Error kit.

 

[Nevada Ed]

My old 38 special die was bought back in the 60's............

It started to scribe lines on the brass cases, so I took some steel wool to the inside
to see if it would help, which it did, a little. I can live with it, for now.

60 years and still ticking..............

 

[GB]

Yes sir! Easy to do. I use jewler's rouge but any mild abrasive polish will work. I have polished out several rifle dies that scuffed up cases and even fixed a carbide sizer or two..

 

[M29since14]

You can polish the die yourself, particularly if you have a lathe, or some other convenient (but safe) way to spin it, but I’d just send it back to RCBS. They have polished a couple of my rifle dies that weren’t quite up to snuff when purchased. I don’t know of a company that does a better job with customer service. They’ve always been very helpful when I’ve had need to call them.

 

[DWalt]

I had a Lee die set, and the FL die had a slight burr inside it that caused case scratching. I called them, and they just asked me to send it back to them and they replaced it free, including return postage.

 

[Ruger 13]

What are you lubing the cases with?

 

[IrishFritz]

I regularly clean my sizing dies by using a tight fitting bore brush with powder solvent spun with an electric drill. This may work if the cause of your scratching is some kid of material adhering to the die wall. It won't work for a machining imperfection, and if that is the case, then the die needs to be corrected by RCBS

 

[342ti]

That's why you lube your cases Bud

 

[gwpercle]

I have done it with a snug fitting brass cleaning brush wrapped with 0000 steel wool dampened with a little gun oil .
I usually do it by hand but a set of old Bonanza Dies needed the use of a cordless drill to polish out all the crud from sitting around for 40 or 50 years ... the dies had never been used but were coated with a cosmoline like coating and some surface rust ...they cleaned up nicely .
For extra polishing , after using steel wool & oil , smear the steel wool wrap with J-B Bore Compound (or any extra-fine polishing compound) and polish the interior with the power drill untill nice and slick .

It sounds like you have a tiny spec of grit embedded in the sizing die wall (scratches and brass streaks)... a good polishing should remove it .
Ditch the One-Shot and get a better lube . I also like and use Lee Case Sizing Lube but the absolute best (although messy) is a little STP Oil Treatment ...that thick greasy compond will resize and reform cases better than anything ... you have to wipe it off when done is the only down side ...but it Works !

Gary

 

[scattershot]

I’ve never had good luck with One Shot either. Try some pure lanolin (sparingly). As far as the die goes, I can’t offer any advice, but once you get it cleaned up and change Lube I doubt you will have any more problems.

Good luck!

 

[Hasbeen1945]

I’ve never had good luck with One Shot either. Try some pure lanolin (sparingly). As far as the die goes, I can’t offer any advice, but once you get it cleaned up and change Lube I doubt you will have any more problems.

Good luck!

No luck here either. Every time I tried it I nearly stuck a case.
Imperial wax for me.

 

[Krogen]

Send it back to RCBS. They will take care of it. The few times I've needed support from RCBS, they were stellar.

 

[DWalt]

Switching the topic to case lube, for many years I have used STP. I have been drawing from the same can of STP the whole time. I usually dilute it a little with mineral spirits before application to my pad (an old and fairly large stamp pad). Some swear by Johnson's paste wax as a case lube, but I have never tried it. Ditto Lanolin.

 

[Mike in Reedley]

I bet Imperial Sizing Wax will make your problem go away.