| 摘要 |
<p>The seal band, comprising an anti-slip ring (6) that turns on a support (5), incorporates a copper ring (7) of the same diameter as the gun barrel. The copper ring, which has a thickness no more than 5 per cent of the barrel calibre, is located in front of the anti-slip ring and is of smaller diameter than the latter. It is held at a set distance from the anti-slip ring by a spacer (8).</p> |
