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View Full Version : Lee .401 Cast Boolits in Springfield EMP



mikeyd499
01-03-2017, 01:16 PM
I have just acquired a Springfield EMP 40 for my EC. I am wondering if anyone has tried cast in one and how did they work out. Which Lee bullet works better, TL or regular? Pros and cons of each. I have never cast for a semi-auto, only for revolvers so far. Any tips or hints would be appreciated. Also if anyone has a few extra of the aforementioned bullets they would like to share, I would gladly pay shipping. Just a few to try before buying a mold.

Taterhead
01-03-2017, 06:47 PM
I could send you some of the "regular" lube groove Lee 401-175-TC. They weigh about 179. All mine are powder coated with either Smoke's signal blue or HF Red. If you're ok with PC boolits, id be happy to give you some. I have some sized 401 and 402. My alloy is about 3% Sb 1% Sn.

The boolit is nice, but I didn't particularly care for the mold itself. I have added NOE and LBT molds in 40 bore, so the Lee is going to be put on hiatus for a bit. Mine's a 2 cavity.

Taterhead
01-03-2017, 07:08 PM
As far as tips go... the critical thing for the 40 and 10mm is finding an expander plug that has the correct shank diameter. The standard shank diameters (at least on my RCBS dies) is too narrow for cast. NOE has an expander m plug that is suitable for a 401 diameter. RCBS has a 401 Cowboy expander plug that is the right shank diameter, but the shank is too long. I called about the specs for the RCBS Cowboy expander for the 38-40 WCF. I have two on special order from Midway to see if they are right. In the meantime, I had a friend shorten and contour a 401 Cowboy expander plug. It is working fine.
The RCBS expander plugs are "M" style, and that
is my preference.

The other thing to think about with auto loader is the taper crimp. A bit of a misnomer since best results occur when just crimping enough to close up the flair. If the expander plug is correctly-dimensioned, proper neck tension will result. A taper crimp will not do much to correct improper neck tension. I make a habit of seating and taper crimping at separate stations on my press.

I like 452AA powder (the predecessor, and very similar, to WST).