You really limit yourself and the capabilities of your carbine / rifle with a 50-yard zero. For the majority of AR shooters, a 100 yard zero is most practical, regardless of bullet weight. The gun will shoot a little high at 50 yards and a little low at 200.

You'll need to confirm the exact above and below at 50 and 200, but it won't be much. Additionally, if you zero from a good solid padded benchrest and then shoot offhand, prone, or what have you, the zero will likely be affected.

Every shooter is different when it comes to skill, firmness of hold, etc., so it's important to shoot using different positions to see where your gun is shooting, i.e., point of aim vs. bullet's point of impact at various distances.