So ive reloading 223 and 308 for a couple months now. But then i just thought do i need to resize the brass if its at 1750 or 2005 or under respectively. Not able to find a good enough answer googling it. Whats your thoughts/common pratices out there.

Trimming and resizing are two different things brother. If its shorter than 1.750 then there is nothing to trim. 

If you are using that brass in a semi auto then you need to resize every time.

If you are using it in a bolt action than you can fire form that brass but you still may need to trim it.

Thanks. When i resize the brass even if its 1748 it then makes it longer depending on the brass Then i have to trim it. Why's that ? Yes its in semi ar's.im using rcbs small size dies for ar's. Why is it labeled small size?

No matter what you must resize the neck -- How's it gonna hold a bullet?

 

If you are using the same brass in the same gun then neck sizing is the only requirement -- as long as it's not an autoloader -- your rounds will potentially be more accurate this way

 

Semi auto gun,  for consistent feeding, you should full length size everytime

Gotcha. Just thought i could be lazy. Back to work for me.