What's a good load for breaking in a new SIG P226 .40?

What grain?
Standard or +P?

I've had a SIG P239 .40 for a little over two years now.  I wouldn't worry about shooting +P throug it.  Standart should work just fine.  I did my 1st 300rds w/ 180 grain Blazer CCI, but that's just what my PD had at the time.  Any manuf. should be fine, but I'd stay away from foreign rounds.  The Blazers are steel alluminum casings, and are a little more dirty than some better brass rounds, which will just make your gun a lil more dirty, but no harm done.  I've shot a few hundred of 162 grain, and noticed a lil more of a "bitch factor", which was nice on the range.  Gold Dot, and Fed Hydrashock make good defensive rounds.  

Bottom line:  Buy a cheaper ammo for the range, and after a couple hundred rounds, you'll notice your gun becoming a lil more smooth.  

NICE BUY, and HAVE FUN!

I would try lots of different ammo through your pistol to make sure it functions with them. I personally shoot whatever is the most economical at the time.

+p would probably break it in faster, I would pick up 1000 rounds of whatever ammo is cheap and have a fun day at the range getting it broke in. PMC is pretty good ammo and you can usually get it fairly cheap I shoot mainly S&B in my handguns.

                              Jonathan

There is no such rating as +p for the .40 S&W.