How I fixed (totally by accident) a bunch of loose primer pockets.

[Tim K]

I had 150 or so pieces of Lapua .260 brass I'd overcooked. Some primer pockets were a touch loose, some so bad the primers would fall right out.

I tumbled the brass for a very long time in SS pins. So long, I did all kinds of damage to the case mouths that had to be repaired. There's a thread on this here in this area. I got them all trimmed up and went to prime them last night. I was all prepared to glue the primers in to get one last firing from the brass.

To my amazement. the tumbling tightened up the pockets. Out of the entire pile, I didn't have a single case that wasn't tight enough to retain the primer. In the vast majority of cases, the seating actually felt pretty good. I'm guessing it wont last beyond the next firing, but I'm about as happy as can be.

I'm also not dead sure that the tumbling is what caused it. I can't think of anything else, but it's a surprising result. If someone else has some brass with loose pockets and a SS tumbler, I'd love to get confirmation.

[thedave1164]

Nice!
No experience here

[Mazin]

Cold water tumble? I got nothing else to suggest as to why the shrunk back up.

[TheBelly]

Tim,

How long did you tumble? I have about 15 pieces of SSA .260 brass that have the looseness in the down-low also. I'll get it started tonight.

[thvigil11]

Are the pockets concentrically shrunk or just pinged? Hope you do get another firing out of them, but I would watch for blown out primers and loose primers in the action (if its a semi auto). You certainly have had an interesting time of reloading lately. I've found your posting to be very informative and thought provoking.

[Tim K]

It had to be 12 hours or more. I might have forgotten it was running...

[thvigil11]

After the 3rd time of leaving the tumbler on for a day or more, I got a countdown timer and put it in the wall. Since then its been pretty nice to set it up and forget it.

Its this one here.
http://www.homedepot.com/p/Defiant-15-Amp-Outdoor-Plug-In-Mechanical-Dusk-to-Dawn-Countdown-Timer-with-Grounded-Outlet-49824/204209975

[NFATrustGuy]

After the 3rd time of leaving the tumbler on for a day or more, I got a countdown timer and put it in the wall. Since then its been pretty nice to set it up and forget it.

Its this one here.
http://www.homedepot.com/p/Defiant-15-Amp-Outdoor-Plug-In-Mechanical-Dusk-to-Dawn-Countdown-Timer-with-Grounded-Outlet-49824/204209975

I put this timer together using parts and pieces from Home Depot. The blue screen is a touch screen and you can set it up or down by the minute. I need to build another one or two… Don't really know why the picture is sideways, but you get the idea...

http://www.woodardfamily.com/hosted/timer.jpg

[Great-Kazoo]

sounds like the steel pins peened the pockets over just enough. Also sounds like leave at the range or scrap brass after shooting

[Tim K]

Yeah, the whole exercise was to get some brass for a match where it would be better to just leave it on the ground.

[skullybones]

Probably similar to "peening" a loose press-fit pin hole with a ball bearing.

I wouldn't recommend people to make a habit of it, but striking a ball bearing with a ball peen hammer centered over the affected hole will create a semi-suitable press fit. With pins also apply Loctite 609 retaining compound to help fill any small blemishes/ gaps in the pin hole.

Save a couple pieces after firing, and I'll bring a ball bearing over to test this theory.