并且靠稍微偏移后瞄准座来修正大型火炮因膛线所带来的偏流。

Correction for drift caused by the adoption of rifling in big guns was approximated by inclination of the rear sight bracket.

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这种瞄准镜底座是可以转动的，使得瞄准线能够偏离炮膛轴线以修正射程，偏流及火炮与目标之间的相对运动。

The sight telescope was mounted in such a way that the line of sight could be offset from the axis of the bore of the gun to correct for range, drift, and relative motion of gun and target.

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