congrats on your adjustable gas block purchase. when you go to tune your new adjustable block, i suggest going for minimum setting to achieve last round bolt hold open + just a little bit. That way you should be able to shoot your gun both suppressed and unsuppressed without any adjustment.
let me pose some food for though.
one thing you have to consider - most (production grade) 16" carbine gas barrels are intentionally overgassed out of the box. even unsuppressed. manufacturer's would rather have a gun run a little hard to makeup for people using crappy ammo or lack of proper maintenance than to have to deal with tons of warranty claims as well as the internet black eye they get for their firearm not functioning well. seeing as thats probably the most common entry level configuration out there, better to make that first time buyer happy that their gun always goes bang while they learn the platform than the opposite. so dont be shocked if you have to dial back quite a bit before you get it set to where you want it.
as arlaunch mentioned there's a couple ways to go about correcting this - that being tuning your lower or tuning your upper.
I've always favored on the tuning the upper tract for one simple reason - unless you have a dedicated lower, your tuning may well interfere with the operation of another upper on that lower.
by tuning your upper to work with a more standard configuration lower (standard spring, carbine or h1 type buffer, etc) you can easily swap calibers/uppers and not have to worry about them not running on your specially tuned lower, or having to remember to bring different buffers/springs with you to the range to swap around.
likewise, if you were to transfer your upper onto another non-tuned lower, you're back to facing the same issues you started with.
im not suggesting that either method of firearm tuning is *wrong* or *incorrect* in any way.
simply that tuning the upper to properly manage the gas flow leaves you a lot more flexibility than tuning the lower to manage an overgassed system does.
HTH
