I'm planning on building another carbine AR 15 soon and I'm trying to decide what kind of barrel I want to get for it.

I'm planning on using a NFA LW 15 polymer lower with a mil-spec buffer tube and a metal parts kit. I'll be using a magpul moe handguard on the upper to keep weight down.

I want my new AR 15 build to be lightweight and fairly accurate to about 150 yards and less. I want something that I kind shoot at the range on a table and something I could carry around that doesn't way too much.

How much lighter would a 16" M4 barrel be, compared to a 16" HBAR?

Would you notice accuracy lost on a M4 compared to a HBAR at 150 yards and less?

Thanks