I shoot an inline 50cal, so I use these types of speed loaders, but with two compartments:
https://www.amazon.com/Muzzle-Loaders-Magnum-Speed-Loaders-MZ1617/dp/B08KWN79CT/ref=sr_1_13?sr=8-13
They fit great in these MOLLE pouches that can be attached to anything from my packs to my belt.
https://www.amazon.com/TRIWONDER-Tactical-Cigarette-Military-Battery/dp/B08F7SDZPT/ref=sr_1_2?sr=8-2