Never willing to leave well enough alone, I grabbed one of the big blue ones. These are twice the size of the red ones.
It has a problem, the retaining lips are ... two.. and spread out. Not entirley sure if it would grip tight enough to hold a few hundred rounds etc.
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So, while I was at the hardware store with blue bin in hand, I went to over to the welding section and picked up some |_| shaped aluminum.
I already have a bunch of screws and washers and stuff other projects.
First thing to do was cut off the two existing lips on the back of the bin so I could mount the piece of aluminum.
Then it's just a matter of drilling some holes.
Now, I do happen to have a tap and die set, but aluminum is pretty soft and with some english, you could easily use the screw to thread the aluminum itself.
I ended up with:
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Sliding it onto the bin holder thingie on the press showed a concern...
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But... I happen to have some jumbo crafting sticks laying around from the copper plating supply / experimenting, and two of them are a PERFECT shim. It's snug, nothing moves at all, etc.
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Blue bin: $1.69 (the small ones are like $0.69 and require no effort to use).
Aluminum thing: $5 i think ? with plenty of metal left over for other uses
Ideas: something along the inside of the |_| aluminum to act as a shim so don't have to use the craft sticks. Do I care ? Not particularly...
I've not loaded ammo with the blue bin yet, there's some concern that the the lip of the ammo deflector, a dip to the aluminum piece, then the edge / lip of the blue bin might cause problems. Easy enough to fix, but it's a possible issue.