But the barrel on tested railguns, Clark said, had to be replaced after about 12 to 24 shots were fired.

克拉克表示，但是已测试轨道炮的炮管在发射大约12到24发后就必须更换。

A normal gun can be fired about 600 times before the barrel has to be refurbished. But the barrel on tested railguns, Clark said, had to be replaced after about 12 to 24 shots were fired.

在必须翻新炮管之前，普通炮可以发射大约 600 次。但克拉克说，经过测试的轨道炮上的炮管在发射了大约 12 到 24 发后必须更换。