Magnums are named that for a reason, they are exceptional cartridges that require a particular skill to shoot or load for.
Magnums are named magnums as a marketing tool. The .32 H&R "magnum" is a pipsqueak round and unless you hotrod it and go outside the lines (many have), it's like loading .38 Special. Which is like loading .357 Magnum. Which is like loading .327 Federal or .44 Magnum.
Rifle loading for accuracy is a outrageously more complicated and difficult to fine-tune than any of the cartridges we've mentioned thus far.
Want to get in to complicated or skill-testing handgun rounds to load at the bench? 5.7x28 is a good candidate. .357 Sig, perhaps, has a few angles that are different than straight-wall revolver rounds. .25 Auto is probably a fun one to deal with, I'd guess.
.327 Federal may not be widely popular and known, but the level of difficulty is much less than loading the cartridge most
similar to it in world--.30 Carbine. (which I load for handgun) Much less difficult than .30 Carbine.