Not for a similar length, but on both sides. I have a Ruger No.3 (22") and a Contender (10").
First off, loading for the Hornet isn't quite like other cases, the brass is about paper thin at the case mouth, and care is required. Expect to lose a few cases especially in the beginning. I recommend a generous chamfer of the case mouth, and very carefully starting the bullet and seating SLOWLY, so you can feel if something goes wrong. NOT a good round to load on a progressive, unless you like buying brass.
The Hornet does its best work with bullets 50gr, and under. Its not a magnum, don't try to make it one.
Loading for a single shot, COAL isn't critical, as long as you stay off the lands.
Plenty of data in the manuals, the Hornet has been around a long time. DO pay attention to "hornet bullets", pre WWII Hornets often had .223" barrels, and bullets in both .223" and .224" are out there, still.
I expect your M6 will be a .224" bore. I have no idea what kind of accuracy to expect, sometimes they can surprise you, but it isn't built to be a target gun.
Careful loading can get you up to 2600fps with a 50gr out of a 22". From an 18", probably 100-150fps less, or so. I've had good luck with the old Winchester 45gr HP, don't know if its still available.
I use small rifle primers, and 2400, other powders work too, and some guns shoot better with some powders than others, so if you aren't getting the accuracy you want with one, try another.
Good Luck