My reference to "factory bullet" refers to the more common truncated flat nose bullet found in much of the "plinking" .40 ammo...none exactly the same probably but much is similar....There are hundreds of bullet styles..no question...different weights, different ogive characteristics, different uses, different materials, etc....
I went through a big dog and pony show about 8 or 9 years ago with the original style model 97..I decided I wanted to use the Hornady self defense bullet and began to look it over and discuss it with some folks...The way the older CZ was built made it pretty picky on bullet shape, size, style, etc..My intention to follow " a factory style" with the .40 is because I've purposly avoided the .40 for reloading (for over 40 years) as I don't like high pressure loads in handguns..my feelings were that the more common style of plinking bullet for the .40 would give me a bit more comfort in getting acquainted with the round as I began loading it....being 80 I'm perhaps a bit more cautious than some....the "end use" for what I load these days is nothing more than punching paper..older, a bit infirm and not hunting nor using the new .40 for self defense would indicate my "selection" for what I intend to use the bullet for...the question is answered...some may think that just loading to shoot is a backwards goal...I've done plenty of load development and experimenting...but today I just enjoy the fun of shooting my own ammo...and I've got friends that load and it's a place where I can meet with guys in my age range and just chat...we've all already "proved our stuff" over many years so now it's just part of a much bigger picture.
It's like when we began to load wildcat rifle rounds in the late 50's and early 60's..things like the Ackley improved's, the 25-06's, the 30 Gibbs...there was hardly anything to go by and we went ahead any way...our testing was to tie the rifle to a spare tire and yank a cord to fire the rifle from a distance away..if it survived...we felt we had a shootable load...These days, even with the huge amount of data..I still move very cautiously...I'm sure you would wonder about my reluctance to shoot the .40 in 200 grain loads or even down to the 180's...my comfort level right now would be with the 155-165 grain bullet in a style that I'm pretty sure will load in the 75B chamber and feed with the stock CZ magazines...I'll bet there are some of the high end self protection rounds that simply won't fed or work well..but I'd rather not be experimenting right now....I like to load for the loading itself...it's a place where I can focus, be in a quiet area and the output of ammo is a bonus when I shoot it and it works well....I no longer hunt...I don't do any more precision long range shooting...I just enjoy the hobby....I don't even care if it costs more than buying factory ammo....I just like it...that's my 2 cents worth...Happy New Year...