Home /
IMPERIAL MILITARY UP TO .299" /
25 DARDICK TRIPLEX ROCK DRILLING TROUND
Click to zoom
IMPERIAL MILITARY UP TO .299"
25 DARDICK TRIPLEX ROCK DRILLING TROUND
25 · 1 headstamp · 3 scans
| Calibre | 25 |
| In the cabinet | IMPERIAL MILITARY UP TO .299" · 4 images |
Reading the headstamp
12 o'clockMaker's name or factory code
6 o'clockCalibre or year of manufacture
CentrePrimer — Berdan or Boxer, and any seal colour
Research notes
Although not a military cartridge, it is listed here instead of the commercial sporting cartridge section. To overcome delays in drilling due to hard rock formations, the tri-bore (tround) is used to fire three ceramic projectiles to break the rock in front of the drillbit. It was developed by Tround International Inc., together with Dresser Industries.
Below is the tround shown at 2x scale, as well as the drill assembly with barrel
Provenance
2025Catalogued in the collection
Same drawer
