OK, we've got the Springfield back from warranty service; working great with 13.5 grains of AA9 pushing Hornady 180 grain fmj.
I bought a box of 180 grain hardcast (Brinell = 18) and it's time to get to work.
Anybody with any advice?
I use mostly hardcast slugs in my pistols, as long as they are a good fit leading shouldn't be an issue, especially if gas checked or powder coated. I run them just as hard as jacketed slugs.
Bullet/Bore fit is more important than hardness. In Ye Olden Days they killed elephants with soft lead bullets (8 bore and bigger). Size and lube quality are primarily what makes it work. Hit a soft enough bullet hard enough on its base with fast powder and it will obdurate (squish) up to fill the bore. With a hard alloy bullet thats too small hot gas will blow around it and leave leading.
Having said all that, I had great luck with commercial cast bullets before I started casting my own. Use a powder on the fast end and work up. I take a cleaning rod, brush and patches when playing with new lead bullets. Shoot a group, then examine the muzzle end of the bore with a bright light. Sometimes it helps to stick a clean Q-Tip @1" down the bore to reflect the light to the sides. Half a dozen brush strokes and a couple patches to tidy up then shoot the next group. Often accuracy will go bad about the same time the bore begins to badly foul. Then you know you've gone too far for that particular load/bullet combo.
I'm shooting cast bullets almost exclusively these days in 10mm. I have too many 10mm moulds, but they all work great powder coated. It has been stated previously, but it is worth repeating that fit is king. Of far greater importance than hardness. 1 thousandth over groove diameter is great.
I do like Accurate no. 9 for running hard with a powder coated cast bullet.
One quick thing to check. Even hardcast bullets can be swaged (squeezed) to a smaller diameter if using the standard diameter expander. The issue is stuffing a .401" bullet into a .397" neck. The remedy for me is to use an RCBS expander die retrofitted with a "401 Cowboy" expander. It adds a little more diameter to the neck ID, so it cured any swaging problems that I have.
It is catalogued as the 38-40 WCF Expander
https://www.midwayusa.com/product/190552/rcbs-cowboy-expander-die
If you already have an RCBS expander die, just the plug is needed
https://www.midwayusa.com/product/272466/rcbs-cowboy-expander-assembly-38-40-wcf
Note that the pic is outdated. New RCBS handgun expanders are the "M" profile, better in my opinion.
Taterhead's post is spot on and something I have mentioned previously as well. When loading my stuff I use two separate steps for the seating and taper crimping.
Here is why, the bullets especially lead alloy or plated can snag on the casing mouth if there in not enough case mouth flare, but more importantly are the dies themselves.
I use a 1/8" spacer to raise the seater / crimp die avoid having to readjust my crimp setting lock ring. Why 1/8"? Taper crimp section of the interior of the seater/crimp die can start to close the casing in on the bullet while seating if not adjusted so that the case does not start to squeeze in while the bullet is being seated. This helps to eliminate the bullet form catching and snagging the case mouth where it can roll up or shave off bullet material or wrinkle or buckle the casing. We are referring to semi auto where 100% reliable feeding is necessary so any problems where bullet material can pile up (even small amounts) on the case mouth edge can cause headspacing issues or even a failure to completely go into battery for complete slide barrel lockup.
After all of my batch of ammo is seat to proper depth, I can remove that 1/8" spacer, back out the seating stem so it no longer contacts the bullet and apply a perfect taper crimp that will also aid in a smother transition for reliable feeding. These are the most important things you can do to improve you handloaded ammo for reliability and consistency! :)
This can be done on a progressive type press if you have two stations one for seating and another for crimping separately.
Thanks for the suggestions. Long time loader, but it doesn't hurt to ask the more experienced when getting into a new cartridge.
I have from the very beginning used a four-die set for all my loading, both revolver and semi auto. Some say they can seat and crimp at the same time, but I think it's better to do 2 separate steps, especially with led or hard-cast.
Shot my first box of hardcast today, through the new Sprg. Operator. 180 grain truncated cone over 13.0 grains AA9.
Feeding and functioning was flawless.
Accuracy was abysmal, but then, that gun has dreadful accuracy no matter what ammo I put through it.