Made the same post on gunsite but thought it may be of interest here too.
I got a 6 inch Ruger Security Six from a fellow GSer a while back with the intention of fondling it extensively and doing a bit of ICORE, Steel Challenge and maybe even SADPA to irritate SO's who would have to switch from shot timer to calendar when I lined up.
Decided that other than speed loaders i would ghetto grade all the additional gear I needed. That came down to holster and speed loader carriers. Made the holster a couple of weeks back and still have a couple of small changes to make to the belt loops and need to add a bonded in stiffening plate where they're bolted in. It came out better than I feared considering I haven't made plastic gear in a long time and it's ABS, rather than Kydex and is a bit trickier to work with and less forgiving or muppetry. There was a lot of muppetry as I'd forgotten pretty much everything including the goldilocks temperature range for the oven. I wasted at least 5 pressings before i got something usable.
Next up were the speedloader carriers. I saw a design from a guy that trades as JOX in the states and liked it a lot so i decided to see if i could steal the idea.

Worked on a paper pattern for the blank I'd need to cut.
And then formed up a very crude prototype by hand for functional testing
It worked a great deal better than it looked and I realised that starting from a PVC pipe of an appropriate diameter would save me a lot of time and effort. The right daimeter is 40mm but unfortunately that doesn't seem to exist in black in Safferland and i've only been able to find 50mm black for use in solar thermal applications. Went ahead with a slightly refined and simplified version in white 40mm. Changes included the omission of the floor as I can bond one in if it turns out to be necessary and moving the grasping windows to the front and rear of the carrier.
Now that I have the design dialled in I'll make a stiff plastic template for marking up the pipe and crank out some in blue. That is unless anyone can point me in the direction of black 40mm PVC pipe somewhere local. It does exist and i see reference to it in the US and on Chinese sites but not here. It needs to be PVC or some other thermoplastic as the retention depends on being able to push the body of the loader into the heated end of the pipe section so that it makes a tight pocket. The base bottoms out on the cutouts and is then sprung in place by rolling the top edges of the tabs over for a perfect snappy retention fit that is not impacted by the OAL of the cartridges. This desing works equally well for my 38 and 357 loads.