Lead on case neck after firing.

[JeffinNZ]

Team.

I have noticed that after firing my .303 Pygmy I am getting fine lead flake on the very top on the outside of the case neck.

My bullet is one thou under groove diameter and 2 thou under throat diameter as this is the biggest bullet I have. It shoots well enough but the lead is a worry.

What is causing it?

How do I remedy it?

[floodgate]

Jeff:

A. If it shoots OK, don't worry about it, it's a variation of the powder blowback a lot of us fret about;

B. If you DO worry about it, lap the mould out a bit.

floodgate

[versifier]

You might try upping the charge a bit, too, for better case obturation. My Arisaka does it with light pistol powder loads.

[Baron von Trollwhack]

Tell about your bullet alloy. It often possible to cast a bigger bullet with a little change in alloy composition. The lyman 46th editiom reloading manual actually has a chart! That's the easiest fix. BvT

[Bass Ackward]

You can also try annealing your brass.

Or sizing the cases a little smaller to improve neck tension enough that the neck expands out with the obturation of the bullet. Maybe crimp a smidge if you are belling too much.

Or seat into the lands if possible to do the same thing.

Any one of those could help too, so which ever one is less of a pain.

A lot of people think about matching their bullet hardness to the pressure level they want to run. Yet they never think of the anneal on their brass to match the pressure. A successful seal is wanted from both places. Case and bullet.

Might even try some light filler too. (did I write that?)

[PatMarlin]

I think you wrote that John..

[joeb33050]

I've only had this happen once, with too much fast powder in a 300 WM. There was, on some case necks, a lead thing that came off with my fingernail, a pretty big and very thin thing.
When I don't M die = bell case necks I get black stuff coming around the mouth of the case and on the neck, but never saw lead on the neck then.
I think you've got too much/fast powder.
joe b.

[mag_01]

--- OH OH the word Filler oh well could have been worse ----

[MGySgt]

Bass - Yes you did.

After every thing you wrote about why NOT to use fillers - I still do!

Drew

[GSM]

FWIW - on pistol cartridges, I tend to get some lead flaking when the brass is brand new and shiny on the inside. It seems to go away after the mouth of the brass gets a cooked on coat of powder / lead.