I just looked at their web site. Lots of rambling about proper fit in your barrel. First I've seen this talk about a Lyman seater must be used to keep from shaving lead, yada yada.

what does this mean in English? Slug your barrels? seems pretty complicated for loading ammo

He's pretty much related what was common knowledge to experienced cast bullet loaders. Loading centerfire ammo is a little more complicated than reloading shot shells for instance.

If you want to forego slugging your barrel, start by buying a small quantity of cast bullets in the diameter standard for the caliber such as .452" for .45 ACP. If you have leading issues you cannot resolve easily, then slug your barrel. Most times by far you will have no problems with leading or accuracy with the standard diameter if the bullets and lube are of good quality.

Be sure the seating stem is correct for the bullet shape you're using and the use of a stepped expander such as the Lyman "M" die is a definite plus when loading cast bullets. Not so much for jacketed bullets.

Bruce

I'd add, to that, to check the diameter of the cylinder's throats & buy your first batch of bullets to match, or slightly exceed that diameter.

...or avoid the hassles/pitfalls & just reload plated bullets.

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Well, hold on to your shorts. Just getting into reloading? Like everything, there's a right way & a wrong way; an easy way & a not so easy way, to do things. Reloading included. The more you work with it, the more you find out what you didn't know, or thought mattered.

.

__________________
Waiting for the break of day

I've bought Dardas cast bullets and will do so again. I look at all the
detailed instructions on their web site as well meaning information
from a serious cast bullet competitive shooter. But that's not me. And
I have been loading and shooting cast bullets for a long time which
doesn't make me an expert....but my results are usually good enough
for me. So I intend to load and shoot the excellent Dardas cast bullets
the same way that I have been using cast bullets for a long time.

The owner of Dardas is Matt, extremely knowledgeable and one that strives for perfection.
If you want to 'just load ammo' then just get some bullets and do so, if you strive for perfection and are a bullseye shooter you will respect what Mr Dardas says works with his bullets
They are a great product for plinking or serious professional target shooting, it's your choice on how you use them.

Example: Bought a Marlin 1894 in 44 mag. With my hand loads couldn't hit a car at 100 yards. Slug barrel and it's .432, my bullets are .430. Ordered some .432 (from Dardas!) and it's a good accurate rifle.
Slugging is not that hard and Dardas offers sized slugs for most calibers.
His instructions might be a little over the top, but it's not bad advise. Personally I don't care for Lyman dies. The trick for me loading lead, plated or coated bullets (for semi-auto's with taper crimp) was separating seating and crimp.

Like many things in life, there's great vs good vs "good enough". So, do you want minute-of-tin-can accuracy? Or do you want one ragged hole? it's all a matter of degrees.

I found Mr. Dardas to be well, interesting. Suffice it to say I didn't buy bullets from him except for round balls for barrel slugging.
Have always had good success with just the RCBS expanding die. I use bevel base bullets so they go into the case without undue stress or strain.

Newer RCBS dies also have a stepped expander. Bullet will sit nice and straight on the "shelf" generated by the expander, no more wobbling around trying to get it straight before seating. I shaved lots of lead before buying the newer dies. It was after reading Mr Dardas's writeup on the subject that I came to learn what I was doing wrong. Makes perfect sense.

+1 for Darda's. Great info & price.