Full-Length Sizer Die is scratching my brass

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Hi all - a question for the experienced folks here.

The problem: I'm suddenly getting very light, parallel scratch marks on my .223 brass from the Lee full-length sizer die.

I've taken the die apart, and there are several very light raised lines in there which I'm thinking are causing the problem - they're about the same distance apart as the scratches on the brass. If I rub a q-tip around in circles on the inside of the die, I can -just barely- feel the ridges - they're not big/sharp enough to catch fibers from the q-tip, tho.

(Not sure how the ridges would have been formed, unless they're the result of some grit getting in there and gauging out a "trough" during case insertion, with the new ridges being the resulting material moved sideways from the trough - just a guess?)

Anyway, I've got no background in metal polishing, but I'm thinking that some sort of polishing process would be recommended in order to correct this - I don't want to replace the die if it's fixable with a bit of effort (plus it's produced more consistent ammo for me than the Redding version has - I do prefer the Redding seater die over the Lee, tho).

So, what materials/gear/process do I need to buy/follow to best do this? I'm thinking that 50 grit sandpaper isn't going to be the solution here...

Thanks in advance!
 
Use your shotgun cleaning rod with green scouring pad cut to fit, chuck in your drill and polish. 50 grit is too coarse.
 
You probably inadvertently got some dirt in the die that left a small gouge in the die. It might buff out with steel wool wrapped around a brush if its not too deep. You can't get too aggressive as it will change the die dimensions or cause other scratches.
 
get some 1/4 wooden dowel, a fine bodywork paper as 500 or 750 grit, saw a slot down the dowel about a inch, cut a strip of paper a inch wide and wind it around the dowel to close the die diameter, chuck the dowel and lots of light oil spin it in the die, do this for 20 seconds and inspect, that fine a paper will remove the scratch and leave it a good finish, keep moving the dowel back and forth so not to leave any radial marks
 
1) Make damn sure your brass is clean before starting reloading.

2) Take die apart. Mount a drill bit at least 1/8" smaller than minimum OD of die and smaller than the bullet OD so that you don't drill into the neck area in a variable speed drill. Fully wrap the drill bit with strip of old flannel or cotton t-shirt so that it is completely covered with material AT LEAST 2 layers thick, preferably more, and in the proper direction so that it will stay in place when in use. It should fit snugly into the die but not tightly. Slather with Mothers polishing compound. Work it in and out of the die about 5 to 10 times over a 20-30 second interval on a moderate speed from the end the brass goes in. Clean die out thoroughly with solvent and clean swabs. Oil very lightly (oil on swab and wipe it down), put it together, try it out, repeat as necessary. You can also use wood doweling instead of a drill bit.
 
I use a snug fitting shotgun cleaning mop chucked in a drill and J&B Bore paste, automotive rubbing compound, Mothers Mag and Wheel polish, etc to polish my dies.

One of the reasons I went to wet tumbling was my AR15s rifles and the brass hitting the ground and picking up dirt and grit and scratching my dies and brass.

Meaning the wet tumbling scrubs the cases free of any dirt or grit "before" sizing and prevents scratching the dies.

The dies are heat treated and very hard and polishing will not hurt the die or change its dimensions. The polishing compounds are softer than the heat treated dies and only clean and polish the surface.
 
Hey Ed, that shotgun mop sounds like a great idea! That would make it a lot simpler most of the time. Kind of ruins the mop though. I guess some kerosene or paint solvent would clean it up. Do you clean it up, toss it, or store it for later (hopefully unnecessary) use?
 
rick357 said:
Hey Ed, that shotgun mop sounds like a great idea! That would make it a lot simpler most of the time. Kind of ruins the mop though. I guess some kerosene or paint solvent would clean it up. Do you clean it up, toss it, or store it for later (hopefully unnecessary) use?
Click to expand...

I clean the mop with soap and water while its still hooked up to the drill, this gives me a spin cycle. ;)

If Kroil and J&B bore paste is used I use paint thinner first and then wash the mop. I use the deep sink in the garage and a small brush for scrubbing your hands to clean the mop.

If I'm lazy I take the die apart and put the die body in my vibratory tumbler with treated walnut media and let it tumble over night. This method made my dies from the 1970s look like new and removed all the slight surface rust.

Most of the time the scratches are caused by the grit sticking to the inner surface of the die. And its very hard to actually scratch the heat treated hardened sizing die.
 
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bigedp51 said:
I clean the mop with soap and water while its still hooked up to the drill, this gives me a spin cycle. ;)

If Kroil and J&B bore paste is used I use paint thinner first and then wash the mop. I use the deep sink in the garage and a small brush for scrubbing your hands to clean the mop.

If I'm lazy I take the die apart and put the die body in my vibratory tumbler with treated walnut media and let it tumble over night. This method made my dies from the 1970s look like new and removed all the slight surface rust.

Most of the time the scratches are caused by the grit sticking to the inner surface of the die. And its very hard to actually scratch the heat treated hardened sizing die.
Click to expand...

Never thought about running a die in the tumbler to clean it up. I am pretty anal about keeping things clean and lightly oiled, but as usual, sh*t happens when you least expect it to. I'll remember that trick.

I'm really impressed with the bore mop and paste/polish use to clean up the interior of full length resizing dies!
 
rick357 said:
Never thought about running a die in the tumbler to clean it up. I am pretty anal about keeping things clean and lightly oiled, but as usual, sh*t happens when you least expect it to. I'll remember that trick.

I'm really impressed with the bore mop and paste/polish use to clean up the interior of full length resizing dies!
Click to expand...

Sometimes you get a new sizing die that was not polished enough at the factory and the case necks are scratched. The scratches are cause by the neck shoulder junction of the die being rough. And the cleaning mops will compress smaller and polish the neck shoulder junction of the die.

I always preferred bolt action rifles and revolvers and these cases seldom picked up dirt and grit when you are careful at the range. But when I got my first AR15 and the cases hitting the ground my .223 dies were always scratching the cases. So I bought my STM wet tumbler with the stainless steel media to "scrub" the brass before sizing.

But if your firearms do not throw perfectly good brass away and makes you go look for it a vibratory tumbler with lizard litter and Nu Finish also cleans the case well.

If you want to clean and polish your dies you will need the standard treated walnut media with polishing compound. I had a old RCBS die set that I had not used in over 20 years that has surface rust on them. And just letting them tumble in the treated walnut media overnight made them look better than brand new and also polish the inside of the die.
 
JB bore paste on a bore mop, chucked into an electric drill. A .338" or .355" (9mm) mop should fit about right in a .223 sizing die.
 
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Quick update: I had the bright idea of using a bore-scope on the inside of the die - it's amazing how un-smooth it actually looks in there from right close-up... There were several long streaks of brass in there (about 1 to 2 cm's in from the bottom of the die) which looked like they aligned pretty well with the scratches on the brass.

So, I tried the first suggestion of using a chunk of green scouring pad, as it was the only approach I had all the required gear/materials on hand for. Re-bore-scoping showed that it definitely removed a lot of the brass streaking (the strip of pad had lots of brass particles clinging to it), but there was still a couple of larger spots left.

On a hunch, I took a longish xacto blade to (very gently) test the biggest spot of the bunch; it turns out to be a pretty noticeable pit in the die that the tip of the blade would catch in - meaning that it's deep enough that to buff it out would require significantly changing the dimensions of the die.

I ran 50 cases thru the die after the above steps, and the scratching seems to have been mostly eliminated; it's now creating 1 very faint scratch per cycle, where it was creating 7 or 8 not-quite-so-faint ones previously, so things have improved.

At this point, I don't think the pit will be an issue for the brass on it's own; however, it seems like a place for crud to build up if I'm not careful, possibly leading to new scratching down the road.

I would guess that the best idea to avoid this would be to buy a new FL die to replace this one (and be super-careful about not getting grit inside the die in the first place).

Thanks to all for the suggestions!
 
I had the same problem and used a shotgun cleaning brush wrapped with 4/0 steel wool spinning in my drill press. Keep it moving up and down . Don't hold it in one spot for very long. I use the same procedure for cleaning shotgun barrels. It won't harm them and polishes them like glass. Hope this helps.
 
Toss it & buy a new one. I had a similar problem with 38 special Dillon full length carbide sizer OEM die. Switched it out for a Hornady titanium nitride full length carbide sizer die & the same issue appeared.

3rd try with a new LEE FL sizer cured all the problems. (My brass was cleaned & polished each time)
 
Try calling customer service at Lee.
They may replace it for free. Some of these reloading companies have amazing customer service. Likely won't cost you a thing. Lee seems to be very encouraging of new reloaders so you may be surprised at what they are willing to do for you.
 
You can polish any die to remove embedded grit or brass sticking to the die. And most carbide die manufactures tell you it helps to lube the cases.

I spray Hornady One Shot on my pistol cases sized in carbide dies to ease sizing effort on wet tumbled cases.

And new freshly annealed cases are softer and the brass can attach or stick to even a carbide die.

Dillon Carbide Rifle Dies Sizing/Depriming Die
https://www.dillonprecision.com/dillon-carbide-rifle-dies-individual-three-die-sets_8_4_24498.html

The sizing/depriming die is full-length and sized to minimum tolerances to size cases down to function in both semi and fully automatic firearms. We strongly suggest that a headspace case gauge be used to correctly adjust the size die.

For high volume users, such as commercial reloaders, law enforcement agencies, and high power or service rifle competitors, we also offer .223 and .308 die sets with a full-length carbide sizing die. Lubrication is still required, but the increased scratch resistance and die longevity of carbide are of great benefit to these groups of users.

Don't feel bad, I had hard sizing and stuck cases when I first started using Hornady One Shot. Then I decided to fully read the instructions on the can and never had a problem using One Shot again.
 
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I've had a similar problem with my .243 and 6.5 CM dies, both RCBS. Mine only occurred in the neck area of the case.
I polished the inside of the die with a bronze brush well wrapped in a long strip of patch material soaked with Brasso metal polish, then chucked in a drill.
I think what was causing the the problem, was sizing un-chamfered new brass. The square edge on the case neck smeared slightly and allowed some brass to deposit on the inside of the die neck.
Since I started chamfering new brass I haven't had the problem recur.
Brass should be thoroughly cleaned also before sizing or you may have this problem.
 
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