Which of the following is NOT a specification of the M240L?

The M240L is a variant of the M240 family of machine guns that has specific characteristics and specifications related to its design and operational capability. The maximum effective range of the M240L is indeed listed as 1,100 meters when it's being utilized in point target engagements, and up to 1,800 meters for area target engagements. Therefore, stating that the maximum effective range is 1,000 meters does not accurately reflect its capabilities, making it the correct response to the question.

The other specifications, such as the weight of 22.3 lbs, the length of 48.7 inches, and the rifling twist rate of 1/12 right-hand twist, are correct characteristics of the M240L, confirming that these details align with the established specifications provided by military sources. Thus, they correctly describe the M240L and serve to differentiate it from other machine guns in the M240 series or similar weapons.