Been doing a little experimenting,
as I have 600 'once fired' Sako .222 brass coming my way,
fired in 1980 !I had in mind to tumble it, or lemon juice it, vinegar it, or buff it,
and then maybe re-anneal, for a bit of case life,
as 30 year old brass might be prone to the odd neck split, or a hundred.
I accumulate old Sako brass, as in it's day it was regarded as maybe the best for brass content/weight/consistency/drilled flash etc,
but in our neck of the woods, it hasn't been imported for probably near 30 years, so all of it on offer is old, and some well used and abused.
Some lots I've fired, I've lost half through splits, maybe from being worked a bit much, ....whom knows.
I tested some with 10mins in vinegar water, and got a bit of a sheen up from my current lot, which aren't very coloured or oxidised, as they were cleaned up when I first got them,
then I buffed up a few on my little driver/drill and Lee trimmer case holder, using a Nortons Synthetic steel wool '000' pad.
I was a bit concerned that I might be taking metal off, but I measured and weighed, and there was no noticeable alteration in the specs, before and after.
Here's the results;
Original on left at rear, vinegar'd right at rear,
and buffed in the front,.....nice and shiny !
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By the way, the vinegar lot smell good, if you like 'Dill',
only vinegar I had was in the Gherkin jar !
cheers,
SS