The only brass I've had a problem with due to thickness is what I call 'one shot brass'. That's brass that is so cheap and thin that it is only good for one shot and ain't worth reloading. They are often separated when you find them and make a ridiculously high 'ping' noise when dropped.

It DOES sound like your die isn't sizing them down enough. But the bullet being pushed in to a consistent distance also indicates the the bullet you are using needs to be seated deeper for your gun. Stay well away from max loads because deeper seating does cause pressures to rise. I think I have an 'M' type die for expand and flare for 9mm. (bad memory) If that were too big my bullets would be 'moveable' also.

Keep at it. I was frustrated as 40 hells trying to get my 9mms to work in all my guns but success is sweet.


PS: Before I had all the answers, I complained to S&W about my problem with the Shield and they put in a new barrel. Since all they have to do is stick a gauge in the chamber I assumed (maybe incorrectly) that there was some sort of issue there, but they may have just put in a new barrel and sent it back.

PPS: I did have a problem with a batch of bullets I got from manufacturer that I really like. Some of the bullets weren't sized properly and others fed and shot like a dream. So check a big sample of your bullets.

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"He was kinda funny lookin'"

First thing to check is your expectations. Tough to make reloads that have NO setback. Check some factory loads by loading mag with one round, then releasing slide using slide release from lock back. of course using adequate safety procedure. Last time I checked multiple factory 45 acp rounds, only one maker had a factory round with only .001 inch setback in the pistol used.

Up to .003 inch may not be an unrealistic amount of setback on reloads, which is why common advise is to not keep rechambering the same round.

Lee will make you a custom .380 undersize die if you ask and spend. Like others have said, flatpoints generally are seated shorter than round nose/hollow points.

For the .380's owned, bullet pull was the concern for reloads.

Kbm
Did you get this issue resolved?
If so, it would be nice to know what was happening

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I'd like to agree with you BUT

I just reset all dies again and made some more
Dummy rounds. The plunk test is passed with an OAL of .969. No noticeable setback after one chambering.

So I made 15 rounds, 5 of 2.7 grains, 5 of 2.8, and 5 of 2.9. All chambered, fired, and extracted fine. Gun was accurate enough. Hit a tin can on the ground at 10 yards. Can't expect much more than that out of such a tiny gun.

So I'm settling on 2.8 grains of HP38 and an OAL of .967-.969.

Thanks to all for the help.

And I'm pretty satisfied with this gun. No light strikes. No fails to function at all. Don't mind the trigger pull at all. Long but smooth. Only complaint I have is the tiny safety. Wish it was a bit wider. I can use it well enough but wish it was a tad easier to get a hold of.