What would be your preferred barrel length for shooting up to 150 yards only and using the gun suppressed for home defense. Talking a 5.56 here. I was thinking that a 14.5" barrel would optimize these requirements - any ideas?

You're right & that is my recommendation. With an LPVO or some sort of red dot / holographic sight

Unless you have an SBR permit though, just make sure the overall length with the muzzle device is 16", min. & pinned & welded.

MM

If you’re willing to SBR I’d go 11.5”.

Yep if SBR, 11.5”. If not I’d go 16” so you’re not boxed in with the same rail and muzzle device.

I second all the above. Spends some time with a 11.5 build topped with an LPVO and you'll make good hits a lot further than 150 yards.

Suppressed.
Home defense.

What are your options for an Integrally suppressed barrel?I can imagine moving around inside with a can on the end of a carbine, much less a rifle.

Yeah, the 11.5" is fine out to 150yds and then some.

11.5 or 12.5 is all you need for that distance.

I think a 14.5 inch with a mid length gas system can shoot phenomenal. If you get the pinned on suppressor attachment you do not lose anything. Having the pinned muzzle device is really nice as you don't have to worry about it coming unscrewed one day while trying to take your suppressor off. Just make sure you go all in and buy a system that comes with the gas block pinned.

The Geiselle URGI or similar comes to mind.

Mine shoots around 1 inch groups and is as smooth as a rifle system. Don't forget to buy a sling and a flash light.

This my 14.7" pinned/welded, mid-gas. One of my favorites.

Enlighten me. Why use a muzzle “device” at all with a +P .223 ? Why not just use another 1 1/2” of rifled barrel if you’re going for 16” total?

Some want the inherent ruggedness and crown protection of the flash-hider, along with the ability to cut down on the flash, and would rather have one than not. Adding one to a 16inch barrel yields something more like a 17.5".

Yes I get the overall length reduction of a 14.5 vs a 16 when you’re adding the cage. But the bird cage type device is a loud son of a nun without a gain in velocity and with no real need for a reduction in recoil. Each his own I suppose.

True. For target shooting or even hunting, I'd also prefer a standard rifle crown, provided there was no option of going suppressed. That's what you see on most 20-24" AR barrels that are hunting/target barrels.

To me, a 16" 5.56 with a bare muzzle, is noticeably louder than the same with an A2 compensator/flash suppressor. The simple A2 comp also directs less gas toward the ground.