[Donatello.]

Unsure of what to build with Geissele complete lower (Aside from lightweight being the goal)

I have a complete Geissele SD lower sitting around, but not sure what I want to build with it. I do know that the goal here will be lightweight. The goal will be to have it weigh about 5 lbs before accessories & can are added. It will just be a range toy.
I'll likely swap some of the existing lower parts with lighter parts, but the receiver itself & trigger will stay. Well, maybe I will replace the trigger with a Larue MBT-2S I have in the parts bin and sell the SSA-E X Lightning bow lol.

It will be run suppressed full time. Kicking around the idea of finally diving into the world of low mass BCGs and adjustable gas blocks. I do know that will end up with a Fostec handguard on whatever I build.

I already have a 16" barrel AR, 10.5" AR pistol & 14.5" AR along with a 22LR rifle, 22LR pistol & AR9 pistol. I did think about doing 300 blackout, but not really wanting to add anymore calibers. Outside of that, I have no clue what to build. I know I don't want to build a dupe of what I already have.