CZ75b-sa in .40 S&W

[unclebart]

Just purchased a new cz75b-sa in .40 caliber. Wonderful pistol! Natural pointer for me and functions flawlessly. However, there is a fly in the ointment. It leads badly due to the fact the Bbl. slugs .403 diameter. My alloy is Lyman #2 and does not cause problems with any other pistol or rifle I have cast bullets for as long as I do my part. Will try some as cast bullets that are .403+ and see if they will even chamber. Have searched for replacement Bbl. with no luck so far. E-Mailed CZ just now and will hope they can tell me something.
At 15yds I am getting 6 inch groups off hand and about the same at 25yds using a pistol rest. I know this pistol wants to shoot. My load is a Lee 175TC, sized .401, lubed with SPG/5 grains unique/WSP primer/Mixed range brass, mostly Speer and Federal. Can anyone here offer a solution or had this problem?

[chutesnreloads]

My CZ-75 is the 9mm.Bore slugged .355-.356.I've had no leading but after trying 3 different cast bullets,wondering if it's going to work with them.With first one .358 sized they were hitting the target sideways about half the shots.Sized down to .357 they quit tumbling but never grouped particularly well.Two other bullets both sized .356...one also tumbled badly...the other only gave mediocre groups.I've gotten hold of some plated bullets that are really shooting nicely.Not as cheap as cast but better than the jacketed.Hope you get a load you like.
 
 

[JRR]

Unclebart,
I also have a CZ75B SA.  It has a nice trigger job but is otherwise stock.

You wrote that you use the Lee mould.  Do you also use Lee dies, and in particular the Lee Factory Size and crimp die?

The first thing you need to do is pull a bullet and check to see if it is being reduced in size during the seating and crimp procedure.

If the pulled bullet measures less than it did when seating you have your answer.  I use an inside size die from RCBS for the 38-40 round because it measures .399".  Most die sets have a inside die measurement of .394-.395".  This will re-size your bullets undersized in the seating process and the Lee crimp/size die will make it worse.  Guaranteed leading!

My gun's bore is clean, lead-free and shiny in about 2 minutes during cleaning after an extended session.

Hope this helps,
Jeff