| Word | Description |
| Belville | A thin cupped disc spring. These spring washers can be arranged in groups to provide varying degrees of resistance to compression. |
| Bent | The notch in the tumbler into which the nose of the sear engages to hold the tumbler in a cocked position. |
| Bergstutzen | Literally a short mountain rifle but always seems to refer to an over/under rifle with different calibres in the two barrels. Typically the arrangement will be a small calibre in the bottom barrel with a larger above. |
| Cast | The amount the centre line of the comb is offset to right or left in relation to the rib. Cast to the right is referred to as "Cast-On" whilst cast to the left as "Cast-Off" Cast at the bottom of the recoil pad or heel is called "Cast at Toe". |
| Comb | The top surface of the stock on which the face rests when shooting. |
| Double Rifle Drilling | Same arrangement as a Drilling but with two rifle barrels sset side-by-side and a shotgun barrel beneath. |
| Drilling | A break action gun with three barrels. The typical arrangement is two shotgun barrels, side-by-side and a rifle barrel underneath and central. the rifle barrel can sometimes be positioned on top and even on the side with the shotgun barrels arranged over/under. Main use is in Europe, typically with an insert tube in one of the shotgun barrels to provide a second rifle calibre. |
| Drop | The measurement to the top of the comb measured from a straight line projected back from the top surface of the rib. The measurement at the front of the comb is referred to as "Drop at Comb" whilst the dimension at the back is "Drop at Heel". |
| Fan-Firing | A double discharge when both barrels fire almost together. The two shots are so close together that they are frequently mistaken for one. Fan-Firing is a user fault caused by the involuntary second pull of the trigger during recovery from recoil. |
| Heel | The top of the stock at the rear. |
| Pitch | The angle formed by the surface of the heelplate or pad in relation to the rib. This is most conveniently expressed in degrees with a perfect right angle being 90 degrees. Down pitch will be any angle less than 90 and up pitch any angle more than 90. Pitch has much to do with comfort in gun fit. |
| Rake | The angle or slope of the comb in relation to the rib. |
| Sear | A lever that holds the tumbler at cock. The sear is The tail of the sear is lifted by the trigger and the nose engages with the bent in the tumbler. |
| Spectrum | A Choke Tube manufactured by Briley in the USA. These tubes have a coloured band around the tube to enable instant visual identification of the choke constriction. |
| Toe | The bottom of the stock at the rear. |
| Top Strap | Same as Top Tang. The strip of metal extending back from the action, over the top of the grip. Normal location for safety catch. |
| Top Tang | The part of the action running back over the grip and underneath the top lever. The top tang is also the location of the safety catch |
| Tumbler | An alternative name for the hammer of a shotgun. This came into use when the external hamemr was moved inside the action. |