New SBR, 5.56/.300 suppressed build question

[lamar_richardson]

Here is what I am building…

AR lower with (2) interchangeable uppers using same BCG/GB charging handle/suppressor (and hopefully recoil spring).

Upper #1 .300AAC

• 10.5” barrel, 1:8 pistol length gas
• .750 low profile steel gas block
• Radian Raptor gas busting charging handle
• Brownells lightweight bolt carrier – nickel boron
• Silent captured springs buffer kit – interchangeable between springs and buffer weights
• Bushwhacker 46 suppressor multi-cal 7.75” long x 1.5” diameter

Upper #2 5.56NATO

• 12.5” barrel 1:7 carbine length gas
• Adjustable gas block
• Radian Raptor gas busting charging handle
• Brownells lightweight bolt carrier – nickel boron
• Silent captured springs buffer kit – interchangeable between springs and buffer weights
• Bushwhacker 46 suppressor multi-cal 7.75” long x 1.5” diameter

If I am interested in only shooting suppressed supersonic and subsonic, are there any perceived over/under gassed situations given the parts being used and if so, with what platform…5.56 or .300?

I am new to SBR’s / suppressors and building AR’s for that matter, I just want to make sure all bases are covered to allow me to make necessary adjustments when needed.

Given the lightweight bold carrier, using same one on both platforms, I feel that if the captured spring kit is adjustable on both platforms, it will be okay. Not sure if the added adjustable gas system on the 5.56 platform is necessary.

Please advise.