Obturating ring

<h2 id="ballistics-uses">Ballistics uses</h2>

<p>Obturating rings are common in artillery, where the steel or cast-iron casing of the shell is too hard to practically deform to provide a tight seal for the propellant gases. An obturating ring which is called <a href="/facts/Driving_band/HI08q8sS">driving band</a> made of a softer material is the standard solution for that problem. <a href="/facts/Mortar_(weapon)/2vs8xEBx">Mortar</a> bombs also use obturating rings to provide a seal around the projectile.  <a href="/facts/Recoilless_rifle/VPQvTFyj">Recoilless rifles</a> and some artillery use rings with a reverse impression of the <a href="/facts/Rifling/63UWYEdX">rifling</a> cut in them for a tighter seal even at very low pressures.
</p><p>Another obturating ring may be used on sliding/falling breech-blocks from the opposite side of the chamber to provide a tight seal there if the charge is bagged and <a href="/facts/Caseless_ammunition/DDVUBclU">lacks a case</a> (examples include early <a href="/facts/Krupp_gun/bjvClAp4">Krupp guns</a> to <a href="/facts/Royal_Ordnance_L11/xo6o7qGX">Royal Ordnance L11</a> to <a href="/facts/M777/THtYmJDf">M777</a>). The obturating ring provides the sealing that would normally be provided by a <a href="/facts/Cartridge_(firearms)/vjkWaDjM">cartridge case</a>.
</p>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Broadwell_ring/N68BFrJU">Broadwell ring</a></li>
<li><a href="/facts/Charles_Ragon_de_Bange/WsdRYQYD">Charles Ragon de Bange</a></li></ul>

<ul><li><a href="http://www.inetres.com/gp/military/infantry/mortar/81mm.html">81 mm mortar shell information</a>, showing the obturating ring</li></ul>

Obturating ring open-in-new

Obturating ring