im designing a concept handgun (post pics of it when im finished with the design its action is very similar to the iwi desert eagle action but one variant option would be where the front part of the slide which is stationary (on all models) is internally suppressed but it looks as if its part of the slide im thinking of a number of ammo types so far ive came up with the (5.7x28mm, 4.6x30mm, .38-40 Winchester, .35 Winchester self-loading, .30 carbine, 5.8x21mm, 7.62x25mm,) if any one has knowledge of any of the listed cartridges expect for the 4.6-5.7 rounds as im already knowledgeable please give simple answers as to accuracy, penetration, reliability, over all be a good pistol round
Let me first say... please understand that I'm not trying to be negative.
Secondly, are you doing this for a school project or something or is this just for fun? The reason I ask is because a lot of times with these kinds of questions, there's no real possibility or even probability that it has any chance to ever see the light of day, and they often end up being a caliber war or a favorite designer war.
Thirdly, the design and actual implementation of a firearm is a huge undertaking with the need for massive financial backing and other heavy resources. Not to mention, that in all practicality, there's not much that's going to be new in respect to firearms development. If you do have an outstanding idea that will revolutionize the industry, it's probably best not to share it with all 7 billion of your closest friends if you know what I mean.
Forth, internally suppressed handguns are going to be huge! Personally, I'm always more interested in defensive handguns and size definitely matters in regards to defensive handguns. To suppress a pistol, you also have to consider how much noise is acceptable. At the velocities generated by some of the rounds you listed, you'll never get rid of the sonic crack as they're just too damn fast.
5.7x28 = ~2300ft/sec (not possible while maintaining effectiveness or increasing bullet weight)
4.6x30 = similar to 5.7's issues
38/40 = 1160ft/sec (possible with downloaded ammo)
.30 Carbine = 1990ft/sec (not possible while maintaining effectiveness)
.35 Win = 2500ft/sec (same issues)
Not to mention, that in a niche market, like suppressed pistols, it kinda lends itself to a "non-starter" simply because it won't really sell due to the requirements/limitations involved with owning NFA items. It's not difficult, but people seem to be scared to death to own NFA items as they think the system is hard to get thru (it's not if you're not a criminal and live in a free state).
Lastly, as I mentioned earlier, designing something "new" will be difficult. I mean really, I can't think of anything that hasn't been tried in one form or another, and even the really cool ideas give way to more marketable, manageable, sellable items.
If it IS for a design project... let talk about what you've got, and see if people can't help modify it. If it's for the thought of building one in your garage...I hope you're a damn good machinist.
I like ing around with concept stuff, but I just hate to see people get their hopes up if it doesn't have a certain probability of success.