Honing/lapping Lee Sizing die

[30yrcaster]

Hello,

Got the wrong Lee sizing die but it was before I found out 9mm barrels need .358 not .356 and slugging my barrel to confirm it. I've been trying to hone out the die a couple of thousands and it's a real chore to say the least. I read Buckshots "How to hone a size die" and he doesn't mention how long it takes to accomplish such a task. I started on the fine size, 600 grit and soon went to 220 where I did most of it. The die started out undersize @ .3553. After 2.5hrs I'm only up to .3569. I even tried using some scotch brite with valve lapping compound on it. Even wrapped a piece of scotch brite around a wooden dowel and put lapping compound on it and ran it in & out with a drill. Didn't seem to speed things up at all so I went back to the 220 with 3in1 oil rolling it on my leg.

Am I doing something wrong as I would have thought I'd open it up too much and trash the die? Has Lee made these much harder since Buckshot wrote his piece? I'm about to "bite the bullet" and just pay another $15 + shipping for another one.

BTW, I tried to open up a Lyman 450 size die years ago with lapping compound in my drill press and after 1/2 hour didn't change the size at all. Lyman's dies are even harder than the Lee.

Thanks

[45-70 Chevroner]

I think your 9mm barrel is over sized. According to my lyman manual 9mm cast boolits should be sized to .356. The .358 will be ok as long as the loaded round will chamber. That means the loaded round will go into the chamber and fall out with no problems. If it will not fully chamber with finger pressure you might have some pressure problems.

[edler7]

I bought one about 3 months ago that I lapped out .003 (from .429 to .432) with crocus cloth. It 's used to clean copper pipe and fittings prior to soldering. It has abrasive on a mesh so it doesn't clog up and lose it's cutting ability. After getting the die to the size I needed, I polished with some 600 wet/dry. The whole process took about a half hour with a drill press.

Any hardware store should carry it.

[geargnasher]

I bought one about 3 months ago that I lapped out .003 (from .429 to .432) with crocus cloth. It 's used to clean copper pipe and fittings prior to soldering. It has abrasive on a mesh so it doesn't clog up and lose it's cutting ability. After getting the die to the size I needed, I polished with some 600 wet/dry. The whole process took about a half hour with a drill press.

Any hardware store should carry it.

That's a good idea. I usually fortify my emery paper with valve lapping compound and a few drops of oil, the plumber's cloth would work even better, especially with lapping compound added.

Gear

[30yrcaster]

Thanks everyone!!

I wanted to stick with the grit sizes from Buckshot's article but with slow results tried the 'medium' (not sure what grit that is) emery cloth I had instead of the wet/dry paper I was using. I used a wooden dowel with a slot in it, chucked it up in the drill and 15 seconds later I was at .3577. Went back & forth between 320 & 600 wet/dry paper & oil and now I'm right at .358.

Looks like you guys were right about using cloth backed emery or crocus. Sure cuts faster. Could have saved 3 hr of work using it instead. Another problem solved by member of Castboolits.

BTW, many have wondered if sizing with the Lee sizer that's been opened up and if the now loose plunger will push into the base of the bullet and leave a mark. I don't see any marks on the bases of the WW bullets I pushed through but it's only sizing it down 1-2 thousands.

[williamwaco]

[QUOTE=30yrcaster;1478853]

BTW, many have wondered if sizing with the Lee sizer that's been opened up and if the now loose plunger will push into the base of the bullet and leave a mark. I don't see any marks on the bases of the WW bullets I pushed through but it's only sizing it down 1-2 thousands.

/QUOTE]

Don't worry about that.

I have Lee push through dies in .356, .357, and .358. All three have identical push rods. They measure .3525/.3532.







.

[1Shirt]

:coffee:Have opened a couple and have had no problem.
1Shirt!

[30yrcaster]

Didn't want to hi-jack the post about honing out a Lee die, so here goes;
...Thank you
No problem. I'm done honing it out.