How do traitor legions and chaos chapters replenish their depleted ranks?

Do they have to retrieve progenoids as do the Imperial chapters? Do they even bother?

Has the science and medicine become corrupted, or lost it's efficiency over time?

Do they cull new recruits from worlds, or do they secretly recruit those that they observe to be worthy? Are there Chaos Marine talent scouts?

I appreciate answers, both canon and heretical . If here are resources for such things, could someone please point them out for me?

Thank you.

*Spoiler*

In the book, Stom of Iron, the main goal of the Iron Warriors was to raid a huge supply of geneseed from the Imperial fortress on hydra Cordatus. Their plan was to keep some of it for themselves, but most of it was to be shipped to Abaddon, to gaint he warmasters favour.

The main character in the book was seen as an outcast and secondrate Iron Warrior, since his geneseed was a hybrid between Iron warriors and Imperial Fists, their most hated enemies.

My personal opinion is that the traitor legions can harvest, and occasionally do, progenoid glands the old school way, but their selfish nature and paranoia towards their so-called allies will make this an unreliable way of increasing or maintaining their numbers over time. The Dark Mechanicus aren't bound by the same rules and doctrines as the Martian Mechanicus, and have probably invested a lot of time and resources into developing or cloning/mutating geneseed themselves.

After all, almost everything is possible with the power of the warp.

http://wh40k.lexicanum.com/wiki/Chaos_Space_Marine

"The process is a brutal ordeal, differing from the carefully measured program of development used by Imperial Space Marines7."

And then there are folks like Fabius Bile, etc, who look for other ways to create and grow the legions.

also the book dead sky black sun has the same atangonist as the main character from storm of iron in which they detail how they make new chaos marines

Thank you all for your input, and the listed sources will now be added to my "must read" lists.

Your service to the Imperium will be recognized, however due to the need for discretion, that recognition will be classified.

Chaos legions don't have Apothocaries like loyalist chapters do, and thus don't collect progenoid glands. The closest thing they have to an Apothocary is the special character Fabius Bile, who creates a few Chaos Space Marines for each chapter- but no where near enough to cover their losses. A small number of loyalists turn traitor and join Chaos, but still, this is a fairly signifigant hole in the background. The vast majority of Chaos Space Marines are supposed to be 10,000 year old survivors of the Horus Heresy, but realistically, how many could possibly be left after all this time, considering constant warfare with the Imperium, infighting, and just plain accidents? Yeah, Heresy-era Chapters were larger than current 1,000-member Chapters, but still- Chaos Space Marines should be drastically outnumbered by loyalist Chapters. -But Games Workshop has a strong bias toward Chaos, so the painfully finite nature of Chaos Space Marines is never mentioned in the background material. Instead, Chaos is always refered to as having overwhelming numbers- check out the Eye Of Terror Codex for the best example. Realistically, if the Imperium loses 1,000 Guardsmen per every one Chaos Space Marine in a conflict, this is a huge victory for the Imperium, because replacements for those 1,000 Guardsmen are born every nanosecond in the Imperium, but a dead Chaos Space Marine is very nearly irreplaceable...

Adeptus-B said:

That conflicts with some of the fluff that's been written- stories indicate they lie, cheat, and steal to buff up their ranks in addition to twisted recruitment methods.

And over at bolter and chainsword discussed this very issue not that long ago, and I managed ot find the thread again. There are some books and stories referenced to support various views on the subject including both codexes and novels.:

http://www.bolterandchainsword.com/index.php?showtopic=208657