Loading semi wadcutters in nickel 40 s&w problem??

This is the first time I have tried loading anything other than Jacketed bullets and I need an answer. I bought some coated Semi Wadcutter bullets from Missouri Bullet Co. and I am using 40 S&W nickel R&P cases and I had belled them for jacketed bullets. I started noticing a little lead being shaved off of the bullet when installed to col and swaged. I rebelled the cases bigger and the shavings came when the bullet came to the part by the head of the bullet not when it started entering the case. I thought that my belling wasn't big enough so I rebelled them a little bigger. What I am wondering is: Is the lead shaving being caused by the taper crimp being too much or what is causing the lead to be shaved. Not every bullet is being shaved so can someone familiar with Lead Semi Wadcutters and loading Nickel cases tell me what I might be doing wrong?? Thanks to everyone who knows the answer to my question.

Can you upload a picture by chance? Is there a lead ring around the bullet or are you noticing little slivers of lead on your press?


JTD

I noticed little rolls of lead on some loaded cartridges at the rim of the nickel shell, easy to scrape off with a pointed scribe. Not all casings but probably about 20 % of the loaded cartridges although they plunk with no problem and all have the same COL. Is my taper crimp to tight? I opened up the belling so that can't be the priblem, I don't think!!

Back your crimp off .
What is happening, it doesn't matter to jackets, is that the crimp is getting applied before the bullet is seating to depth .
You're probably also under sizing the bullet with the crimp and setting it up for leading. The lead bullet should be about .4015-.4025 vs the jacket being .400 also . Back the die body out about a 1/3-1/2 of a turn then reset your length and se if that helps .

With cast bullets you really only want to just remove the flare and have enough to avoid hang ups and failure to battery . There are exceptions like tubular magazines and powders like H110 where the crimp keeps the bullet from getting pushed into the case and is used to build start pressure. Neither should be involved in a 40 .