POI shift of a front sight on a free float rail?

[danpass]

For example a front folding sight on the end. It's not on the barrel such as the typical FSB is.

Let's say you sling up or dig in the bipod legs and put forward pressure on them.

How significant would the shift be?

[AKDoug]

All depends on the free float rail. Some are stiffer than others.

[the 556 guy]

With a front sight pinned to the barrel, I was shooting 3 MOA at 100 yards.

Then...

With a front site mounted on a troy alpha tube (free floating) on my colt, bearing down hard on a sling mounted to the tube caused an additional 2-3 inches (2-3 MOA) at 100 yards.

This with a folding sight on the tube, not pinned to the barrel. And the front sling mont is halfway down the tube, nowhere near the sight.

Not using the sling as stability got me back to 3 MOA.

Just saying.

[Salty Sourdough]

I've had no issues with my KAC URX II with integrated front sight. It easily holds 3-4 MOA at 300yds with a bcm 14.5 barrel. I haven't tried using a bipod or vfg but I don't notice any flex in it so far. For a buis I couldn't be happier with it's consistency.