How-To Crimping of Revolver Cartridges

WanMan99

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Thanks for the post. I was just given 2000 pcs of .38 special wad cutters (158gr) from a buddy whose Grandfather passed away. I haven't reloaded any wad cutters so I will go looking for info prior to loading a test batch. I have always flared the case mouth as little as possible (easier to do when reloading fmj instead of lead) and used a light roll crimp.
 

EddieCoyle

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Expander dies (at least the good ones) do more than just flare the case mouth.

To account for differing brass thickness, the sizing die should (an usually does) make the cases smaller than they should be. In addition to belling the case mouth, the expander die expands the top of the case from the inside so that all the cases have the same ID where the bullet goes. It performs the same function as the expander ball in a bottleneck rifle sizing die.

You're better off belling the case too much than too little. You'll get better ammo because concentricity is hard to maintain when the case mouth is belled too little. The upper limit on case mouth flare is reached when the case won't fit into the seating die.

BTW, the second to last roll crimp he shows, where he says "I've seen people crimp this heavily..."

Is crimped WAY too much. I mean this one:

Image243.jpg


You should never end up with a straight portion of the case above a roll crimp.
 
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mac1911

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I had a lot of fun at my first run with cast boolits in my 38spl. I went with the seating depth of the hornady manual. Found myself at one of the bands and not the crimp groove. I posted my woes here in the beginning of the year.
 
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