Push thru de-rim die question

[wmitty]

I am attempting to make a punch/die set to remove rims from .22 lr brass and will refer back to MightyThor's sticky from 1/25/08. In post #48 Bullshop mentions using a Lee .224" push thru die and turning the pin to fit the I.D. of the brass as an easy way of derimming. In post #76 of this sticky, Rat-Man gives the dimensions of his Sport-Flite die as being .217", and punch dia. as .195".

I'm attempting to use a .224 Lee as Bullshop suggested and am in the process of reducing the pin diameter. I am currently at .215" and started at .221" o.d. and I'm pushing the pin thru the tops of the cases rather than ironing out the rims. Should I continue to reduce the pin dia. or is there something I'm not seeing that's causing the problem? I have rounded the end of the pin somewhat but didn't want to go much further without asking for your opinions.

[Pipefitter]

Dave Corbin uses a 5mm bolt with the head cut off and the shaft polished with a slight radius.

[jdfoxinc]

Lots of lube. I started backing the jacket out of the die and relubing after the rim is gone. This reduced the number of push throughs.

Also polish the die body.

[MUSTANG]

Sizing the brass (22 LR case) to .224 will result in a core that is not tightly held in the jacket.

My .224 swaging set up is by Corbin. The "pin" for deriming 22LR cases is 0.198" in diameter. The brass "Jacket" when de-rimed in my Corbin dies measure .221 on the outside after ejecting. After a core is swaged into the "Jacket; the measurement on the outside is .2235 with my dies.

In your effort; you may want to consider"Bonding" the core to the jacket by melting cores inserted in the jackets in an oven, then cooling to room temperature. In my Corbin dies; the "Spring Back" of the brass jacket holds the core securely. In your dimensions (.224 outside diameter for jackets), you may need to "Bond" the cores to the jacket to obtain a strong core to jacket adhesion.

[clodhopper]

Every thing Mustang says is true.
But also, die diameter.......................................... ...,.224
Brass wall thickness .008-.010 doubled for both sides -.020
Maximum punch diameter........................................., .204

[tiger762]

With respect to the punch-throughs you're getting, are you annealing first? If so, don't for two reasons:

1. Work-hardered brass will spring back and not stick to the punch
2. Work-hardened brass is strong enough to deal with the punch pushing it through the die

On Ebay one sees half-assed attempts at 22LR derimming dies. Usually they are just Lee 0.224" sizer dies that have been radiused at the mouth. For the reason already stated, they'll make a jacket that will be too big. At best, it will be difficult to get it in the core seater die. At worst, you won't have a tight grip between jacket and core.

The jacket should be about 0.221" after derimming and before annealing. Then swaged out to 0.224"

[bullet maker 57]

Everything already stated. How about the radius of the punch? Flat on top with sharp edge rounded.

Lots of lube.

I anneal after derimming. If you are using Federal brass, it is tougher than most. I would change the punch radius slightly until you lose the punch thrus.

[wmitty]

One step forward, two steps backward. I continued reducing diameter of the pin punch and began getting rims to collapse at about .205" diameter. However, I checked the diameter of the formed jackets and found they were .2258" where the rim had been; so die body is now oversize for whatever reason. I also noticed nearly every formed jacket was cracked where the firing pin had struck the rim (these were formed from Federal brass). I was using the brass un-annealed. I'll try to get another die with a smaller i.d. and start over. Thanks for the replys!

[tiger762]

I agree with BulletMaker on the suggestion to radius the punch.