Nice. Elegance in simplicity. I just don't see myself dragging a washing machine to the range every week.
Our flags are presently on rebar. So, my plan is a removable cap, probably made from PVC with a 20 penny nail as the flag spindle. Your idea of using old cases as the other half of the swivel is perfect and will probably work great. I might just bring the rebar home and drill the ends for the nails rather than make the caps.
I was thinking of drilling out the flash holes and putting used primers back in place as the anvils should make great bearings with a point machined on the nail. But I'll try the flash hole as is, first.
Might also use plastic, stainless or aluminum rod if I decide to leave the that part in the rebar. A nail will rust and kill the bearing properties.
The old case idea was right in front of me and it never dawned on me. Homer Simpson moment for sure.
Oooh... just had an extra synapse fire. A very simple solution is to drill the rebar. Then use a bent wire to hold the flag and drop down into that hole. That's how the biathlon flags I found on line are made. See pics below.
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