Opened Up a Lee Push Thru Bullet Sizing Die

[timberhawk]

Last night I opened up a Lee Push Thru Sizing Die from .4008 to .402. I use this die to size bullets before and after powder coating. It has always seemed harder to push the bullets thru than my other Lee dies. I think it had a little rougher finish.

I used a wooden pencil with some 320 grit wet/dry sandpaper taped to it and a cordless drill to open it up. Just taped a piece of sandpaper to the pencil and wrapped a couple of layers around the pencil and let centrifugal force keep the paper pressed to the die.

Went slow and checked the size by pushing a fresh cast bullet thru at regular intervals.

When I got to .4018, I switched to 800 grit paper and polished it out to .402.

This took about twenty minutes from start to finish. but I wanted to work carefully and slowly as this was the first time I had ever tried this.

Worked like a champ. The die is mirror smooth and requires much less force to size a bullet.

I may use some 800 grit on my other push thru dies, just to remove any rough spots and polish them up.

[DaveInFloweryBranchGA]

Good job and good solution.

[dikman]

A good idea, but I would use wet and dry paper, used wet, working down through two or three grits. This will give you almost a glass smooth finish.

[JD74]

That's one thing about lee dies you don't have to worry about missing them up. I've opened my 356, 358, 401, and 452 same way finishing with 800grit with oil for mirror finish.

[Bzcraig]

I too have done this following Buckshot's directions with great success, only difference being doing it by hand.

[timberhawk]

I started to wet the paper, but the way I did it, using just centrifugal force was a pretty light touch. I also used two different grits, 320 and 800. The 800 grit did produce a mirror finish.

I'll try wet paper on the next one.

I'm gonna try to polish a .358 push thru die to see if it makes a difference in the effort needed to size a bullet.

[bstone5]

The finish inside the Lee push thru sizing die is usually rough.

I polish all of the Lee sizing die and open up and polish the inlet so the bullets have a smooth surface as they line up with the bore of the die.

I also use a small rod to hold the paper but turn the die in my lathe.

[Beagle333]

I have used a pencil with my cordless drill too. It works pretty good.

[timberhawk]

I have used a pencil with my cordless drill too. It works pretty good.

Did you use some sort of wetting agent or dry?

I'm gonna work on a few others and was wondering how much longer the process would take using oil on the paper.

[zuke]

I've made up a set of sizing die's out of 287 die's.
I have a set that start's at 301 and goes to 315 in .002 increment's

[JWFilips]

I customize all my Lee push through sizing dies . Just keep in mind: go slow and I have found the smaller sizes cut more quckly. I like to use brass undersize rod stock from the local hardware store as the mandril. & Always rolled by hand!

(Once you master that . You can customize your lee neck collet dies buy ordering an oversize of your choice De-cap mandril for $10 and then hone out the Collet sleeve for the new mandril to fit! That becomes very easy also ...just go slow
All my Lee collet dies are customized to size for cast boolits also !)