On arrival in Victoria, Nelson carried twenty 64 pounder muzzle loading guns on the lower gun deck. In 1867 these guns had been converted from 32 pounder Smooth Bore guns using the method developed by Captain (later Sir) William Palliser. The 32 pounder was bored out slightly and a rifled wrought iron tube inserted. The gun could then fire a 64 pound 6.3 inch case, shrapnel or common shell.
As a result of the palliser conversion the gun now fired a heavier shell with a larger bursting charge. The accuracy was much greater and the shell hit targets at 1,000 and 2,000 yards with much greater force. These guns were fitted with tangent sights.
The conversion of 32 pdr smooth bore guns was first recommended by General Lefroy and the Times newspaper reported that "the Victorian Government has been the first to act on General Lefroy's recommendations; and twenty 32-pounders and ten 68-pounders are being converted by their orders into six-inch 64-pounders and seven-inch 115-pounders." Argus, 11 July 1867.
"...the lower deck guns have an extreme range of 3,900 yards, but firing from the ship's sides only 3,000 yards, unless the vessel is heeled over to give them the requisite elevation." The Argus, 12 September 1870 |
Below is shown a box of US Friction Tubes (known as Cannon Primers in the USA). One of these Friction Tubes is inserted into the vent hole (V) of a loaded muzzle loading gun. The gun is fired by pulling a lanyard attached to the friction tube's loop.
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| US Friction Tubes Photographed courtesy of Ron Hardy. | Part of the Barrel of a 64 pounder RML Gun from HMVS Nelson Visible is the vent V, Friction Tube securing points for Sea Service Guns S & P, Fixing point for Lanyard Guide LG and Rear Top Sight Bracket RTS Barrel weight is 58 cwt 3 quarters & 0 pounds. This gun was cast in 1862 but converted in 1867. See Peter Webster's detailed explanation below engraving. |
 64 pounder on HMVS Nelson being Fired by Lanyard in 1870 Note Rear Top Sight to left of lanyard. Illustrated Australian News, 10 October 1870 | |
A friction tube or quill* would be inserted into V, and the lanyard attached to the loop.
S and P are for guns prepared for Sea Service use. The Sea Service friction tube needed support when the lanyard was pulled, for the fear that it could break off and the errant pieces being injurious to the bare feet of the gunners. So, a pin would be screwed in to one of the holes. A leather loop on the tube would slip over the pin to provide the support. Two holes were provided in case the pin should beak in the first. The screws of either configuration were just to preserve the holes and threads.
The hole behind the vent LG right back at the rear end of the sight patch is to take a lanyard guide. This also screws in when needed for Sea Service only. This guide has a hole in the center through which the lanyard passes. It has a cross-head on top to take a loop on the lanyard. Placing the loop on the lanyard over the cross-head is a safety measure against accidentally firing the gun. The lanyard is now on a line not obscuring the gunner visually sighting the piece down the axis of the gun, also now allowing for a 'direct' pull on the quill loop.
RTS is the bracket that holds the Rear Top Sight which was part of the original Smooth Bore Gun sight system. The Rifled Gun sights were the Breech Sight and the Trunnion Sight shown below.
 Modern Artillery, 1873 | fig 122 - Tangent Sight fig 123 - Tangent Sight Bracket fig 124 - Dispart or Fore Sight  Rear Top Sight Bracket (fig 123) |
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Side Sights for Rifled Guns |
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 Adapted from Modern Artillery, 1873 |  Cross head (red circle) at left fits onto the bar above. |
 Remains of Trunnion Sight | |
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