I prefer wet tumbling over dry tumbling. I use the Frankford Arsenal tumbler with the mesh screens to drain the water and rinse everything without the worry of lose pins getting everywhere. This is the procedure that works for me.
1) De-prime brass.
2) put brass in tumbler with steel pins.
3) put in one dishwasher pod. Yes! I said dishwasher pod. Don't knock it till you've tried it. The cheap generic pods are okay. If you think that they won't work for you then you can still use them in the dishwasher.
4) pour in water.
5) tumble for three hours.
6) remove cap from one end of the tumbler and replace with mesh screen.
7) pour water out of the end with the mesh screen.
8) while the end with the mesh screen is on the bottom, remove the opposite cap and replace with the other mesh screen.
9) fill 5 gallon bucket with water.
10) place tumbler in 5 gallon bucket of water.
11) move tumbler up and down in water to rinse the pins and the brass, changing water a few times.
12) dump pins and brass in a media separator and spin.
13) remove brass from media separator and place in case dryer for drying.
After the cases are dry, I lube and size as usual. To get the lubricant off of the cases, I wash them in hot soapy water and rinse. Then they go back in the case dryer.
I haven't had any problems with pins remaining in straight-walled pistol cases. The same is true with bottle-necked cases after a vigorous spinning in the case separator.
On the other hand, if your're worried about pins remaining in bottle-necked rifle cases, the case/media separator should take care of that.
As an extra precaution to prevent steel pins from remaining in the bottle-necked cases you can try one of two methods.
1) get a magnetic metal parts tray and tap the mouth of the case in the bottom of the tray. You can do this whether the case is dry or wet. The force of the tap causes the pin (if it's in there) to move down toward the case mouth. The magnetic surface also has the added benefit of pulling the pin. If a pin was inside of the case the magnetic surface will hold it in place to keep it from bouncing out of the tray.
2) Get a magnetic pickup tool and a carpenter nail. The size of the nail is determined by the length and caliber of the case. Get a nail that is narrow enough to fit inside the case mouth and allow for clearance of any pins adhering to the side of the nail. The nail also has to be long enough to touch the flash hole.
Next place the head of the nail on the flat end of the magnetic pickup tool. The nail, now that it's magnetized will pick up any pins remaining inside the cartridge case.
You don't have to use a magnetic pickup tool. That's what I have here and is a powerful magnet. You can use any flat magnet that will hold the nail and that is powerful enough to attract any metal pin remaining inside the case.
My Dillon dry tumbler is gathering dust now. I can never go back to dry tumbling. Too much dust.