So I want to re-barrel an upper to 300 blk. I’m looking to keep it somewhat short and run it suppressed. I’ve purchased the magpul Moe SL carbine handguard and my question is what’s the shortest barrel length that will accommodate the handguard? I’m hoping between 10.5 minimum and 14.5 max on a barrel. I will also be using an A2 front sight, if I can find one. Thanks