Differences in .40 and .45 lee dies.

[2meterB]

The .40 produces a very noticeable coke bottle. Additionally, it "smooths" the brass down to a point.



Iv'e read a few posts that say this is 'pretty normal.' but.. looks odd.

In any case, the Lee .45acp dies do not do this. In fact, they don't seem to really do much to .45 brass at all.

The .40sw dies will flatten out a lot of dings. The .45acp dies seem to barely touch the case. But, I don't seem to have any functional issues with either.

Is this a normal difference in dies for the calibers?

[rsrocket1]

45 ACP is a much lower pressure round and does not blast the case to its limit. If you took factory new .40 brass, loaded light and processed them, they would look like the 45 ACP. The smoothing out of the case is the carbide ring squeezing and scraping/polishing the brass down as it sizes it.

My M&P40 has a pretty tight chamber and doesn't distort the brass very much, but I also don't load to very high pressures. Consequently, the round remains fairly straight walled.

[2meterB]

So the .40 is expanding more, therefore hitting the carbide ring...
And the .45 does not?

[orangeusa]

45colt do to some extent. But that has a reason due to the variety of cases out there since 19th century.

I've used 44mag dies and they do this a tiny amount. Have not tried my 45acp.

[Pauliedad]

I've noticed that as well. I reload .45, .44, .40, 10mm, 38, and 9 and of all the .45 and .44 seem the most smoothed out after resizing.
This may be a stretch but I think the tighter radius has something to do with it as well.

[Fishslayer]

That "coke bottle" can vary with brass headstamp & bullet type.

I get a noticeable bulge if I load a .452 lead bullet into PMC or Win brass because the case walls are thicker. The same bullet in Rem cases makes no bulge.

Are you using the LFCD? It has a final sizing ring that squeezes everything. My .357 loaded with .358 LSWC always have that coke bottle shape. For Big Dog magnums with canellured bullets I trim the cases and just use the seating/crimping die.