British Cannon

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Description

For a more general view of the subject please refer to our article British Artillery Equipment. The present article is dedicated to the detailed presentation of the various types of cannon used by the British Army.

In the 1750s, British cannon (guns) were manufactured as 42-, 32-, 24-, 18-, 12-, 9-, 6-, 4-, 3- and 1.5-pounders (pdrs), the reference is to the nominal weight of the shot. Each shot would be measured against a pair of circular gauges — one maximum diameter (high gauge), one minimum diameter (low gauge). With artillery, the concept of windage is very different than that associated with rifle ballistics. Here, windage is the difference between bore diameter and shot size ― it has nothing at all to do with the atmospheric wind. Often the low gauge is the number identified as the diameter of the shot for a gun, but both elements are needed (McConnell 1988, Page 287-289). By the 1750s, the accepted range for a 12-pound shot would be between 4.403 and 4.476 inches with windage of 0.220 inches; for a 32-pdr, between 6.105 and 6.207 inches and windage of 0.305. The low gauge plus the windage is the bore diameter; it is not the high gauge value. At this time, the windage was 1/20 of the width of the shot.

The British did not standardize gun lengths anywhere near to the degree the French did. Gun lengths were particularly variable among smaller bore naval cannon. At times, the British Artillery would field heavy, medium, and light guns of a certain shot size, but only one or two guns of another shot size. The brass 12-pdr is the best example of the British producing heavy, medium, and light guns, simultaneously. The British based the decision on which gun patterns to manufacture purely on the need for a specific gun, not in the attempt to develop a systematic or orderly scheme of ordnance.

British field artillery was centered on the 3 - , 6 - , 9 - and 12-pdr cannon, as did Austria, Denmark, Prussia and Russia.

Gun Patterns

By the mid-18th century, most of the changes and improvements to British guns were centered on either (1) the strengthening of the barrel of an established gun, or (2) the introduction of light-weight guns. The redesigned of established guns often involved "moving" metal from one part of the gun, where the metal was thought to be excessive, to a position deemed weaker and subject to failure. Concerns about excessive weight were still common, but much of the work to reduce gun lengths had been done by the 1720s. Alternatively, more metal could simply be added to the gun with a corresponding increase in weight.

The performance of 18th-century artillery is easiest judged by looking at changes instituted after any war was concluded. By Napoleonic times when field guns were consistently being made lighter or eliminated from the inventory and keeping the same 5-foot barrel length, the barrel weight of the brass light 12-pdr increased from about 1,010 pounds in the 1750s to 1,340 pounds suggesting the need for greater range and/or durability (McConnell 1998, Page 396; and Henry 2002, Page 14). By the end of the 18th century and among brass field guns, only the "medium" 12-pdr gun remained in service, 6.5 feet long and weighing some 2,020 pounds. This gun was the same length as the 1750s medium pattern but weighed some 400 pounds less. At this same time, the light 6-pdr saw an increase in both length and weight (Old: 4.5 feet, 560 pounds; New: 5.0 feet, 670 pounds — Hughes 1969, Page 29). There is no consistent pattern surrounding these changes suggesting the British evaluated the individual performance of each gun pattern independently. Around 1780 under Congreve, brass 18-pdrs and 9-pdrs were reintroduced into the inventory.

Cannon lengths are measured in calibres, a single calibre being the diameter of the shot used in that particular gun. The cannonball for a 9-pdr had a diameter of 4.0 inches, a 12-pound shot had a diameter of 4.40 inches, and 32-pdrs had a diameter of 6.10 inches. Adding about 1/20 for windage, these values would then represent the bore width. The actual bore length is shorter than the gun length, about one calibre less — the cascable at the rear of the gun is not included as part of the gun length. Cannon lengths were very much influenced by their intended use. The obvious caveat being that as the length of the gun increased, its weight would also increase. There were three broad categories of guns — field pieces, siege guns, and ship guns:

  • Field pieces needed to be light and maneuverable, so the shortest of the guns. Field cannon used fixed ammunition.
  • Siege and garrison guns needed to have barrels long enough so that the concussive forces of the firing did not destroy their own embrasures, these were often the longest guns.
  • Naval cannon were somewhat intermediate, they needed to be lighter than a siege gun, especially on the upper deck, but also long enough to limit concussive damage to their own hull with firing.

Different gun designers would then set the number of calibres for each type of gun with the important measurement being the bore length in calibres. There was a near-constant struggle to reduce gun weights while achieving a high standard of gun performance. There were two distinct but related issues: (1) where the gun design was weak and needed reinforcement; and (2) where there was excess metal that could be stripped and used in the needed reinforcements. Addressing only the first question simply generated heavier and heavier guns. The second element was often much harder to evaluate. Discipline in gun design was needed when attempting to reinforce the breech or first reinforcement without then also adding to the second reinforcement or the barrel chase. Throughout the 18th century, the keen desire to make long-guns lighter was never realized. The successful Blomefield patterns of the Napoleonic Wars did not reduce long-gun weights, particularly as it relates to naval guns. The steady changes and increases in the potency of gunpowder formulations made standardizing gun patterns even more difficult.

As the individual molds would be destroyed with each casting, there was some variation in weights between guns of the same pattern. Gun weights were routinely stamped on the barrel near the vent, but it was not always done. Brass guns were also stamped with a casting date. The gun weights given in the tables below were derived from measuring a "typical" gun for that pattern. Exacting dimensions would be recorded for the same "typical" gun. Until new patterns were established, these "typical" guns were often used for experimentation or to teach cadets at Woolwich Warren.

Designs and patterns were not transferable between brass and iron guns. The differences between the materials mandated the adoption of independent gun patterns, particularly as it related to the thickness of the gun walls. There is no defining proportional relationship between brass and iron guns. Although gun patterns were developed and tested at Woolrich Warrens, the "true" testing only occurred in war. After each conflict, the shortcomings were identified and new patterns developed. During the Seven Years' War, British gun patterns were not fully successful with the common criticism that they remained understrength.

Under the 1736 Regulations, metal strength (barrel thickness) of Armstrong’s ‘heavy’ range of brass cannon is expressed in parts (32 parts = 1 calibre or shot diameter):

  • first reinforcement 33-31 parts
  • second reinforcement 28-26 parts
  • chase 23-17 parts (at the muzzle astragal = 17 parts)
  • muzzle 15 parts

In North America, many of the guns used by Colonial Expeditions (1755-1757) were likely early Armstrong patterns (1720s) or even older guns that were stripped from port fortifications. These guns were recognized as being subject to bursting. In 1760, a new pattern was developed. This more successful Armstrong-Fredrick Pattern was not adopted fully adopted until 1764. Some care in language is needed here. Armstrong had become Chief Engineer in 1714 and then Surveyor General of Ordnance in 1722. In the mid-1720s, Armstrong redesigned many pieces in an effort to increase the overall strength of the guns. Following Armstrong's death in 1742, the cannon were again redesigned (1743-1744). These changes were extensive, but the focus was still on strengthening the gun. Minor pattern changes then occurred in 1753. The Armstrong-Fredrick pattern was a continuation of that work. Possibly, the most important single change was a reduction in the windage. This promoted both an increase in range and accuracy, but with this came an increase in the chamber pressure (Caruana 1989, Page 13). Any reduction in windage came from a reduced bore width; the shot dimensions remained fixed. However, McConnell 1988 (Page 288) does not seem to support the contention that the windage was reduced, leaving this central question thoroughly muddled. Unfortunately, there does not appear to be any recognized convention for separating over 40 years of "Armstrong patterns". Any reference to an "Armstrong pattern" needs to carry a modifier or date. With speculation, the vast majority of the British ordnance used by the Royal Artillery on campaign were brass guns, post-1743 patterns, shipped directly from Britain. This is clearly the case in North America. Campaigns in India may or may not be an exception. The British Navy and all fortifications used iron guns.

By the time of the Seven Years’ War, much of Europe had adopted the French-based boring technology. This change in manufacturing resulted in a marked increase in gun performance and fewer proof failures ― each individual gun was tested with multiple proof charges before being accepted for service. However, British manufactures had become set in their practices and refused the innovation. In Great Britain, the bore was developed from a hollow casting that was reamed out to the final bore dimension. Only in April 1776, did the Board of Ordnance mandate that all cannon be solid cast; by the end of the century, all British ordnance would be bored from solid castings (McConnell 1988, Page 18).

Anything written by Adrian Caruana has the chance of containing an element of authoritative opinion which is welcome in a subject dominated by physicality:

"If Borgard had his limitations as a (gun) designer, Armstrong was a disaster ...... Armstrong's 1732 regulation lasted no longer than he did, both died in 1742. There was a complete redesign in 1743 and 1744, a partial redesign in 1753, and finally the regulation of 1764, which was the result of proposals put forward by Charles Frederick, the Surveyor of the Ordnance, in 1760....By far the best designer of guns was Thomas Desaguliers, whose output was small but significant. He designed only brass guns, which were long and slender, but which shot well and were very reliable." (Caruana, 1989; Page 13).

Cut-guns existed, but they were extremely rare by the mid-18th century. Here, the barrel would be shortened to reduce weight, making the gun more maneuverable, or to remove damage. The new weight and a date would then be stamped near the first reinforcement or on the cascable. The same stamping protocol was true for a bored-up gun, where a corroded barrel was reamed out to the next higher calibre — e.g., an 18-pdr being reamed to the bore width of a 24-pdr. The two 32-pdrs at Fort William Henry (1757) may have been bored-up guns (24-pdrs), their weights were only 4,600 and 5,000 pounds, considerably less than expected (Pargellis 1936, Page 128).

Older guns could be sound, age alone is not a factor. Iron guns needed to be parked and maintained with a dry bore, the vent sealed and protected, the bore capped (tompions), and the barrel orientated slightly downward so that the gun would drain. If water was allowed into the barrel, iron guns would rust, loose metal, and honeycomb. Promoting drainage and some method for allowing atmospheric gas exchange were key. In British North America, the "abandoned" condition was the rule rather than the exception.

During the 1700s, the quality and potency of gunpowder incrementally increased. Although frequently misrepresented in histories, the maximum service charge regulation of 1/3 (gunpowder : weight of shot) was not formally adopted by the British until the 1764 Regulations. Broadly speaking, half the weight of the shot may be more appropriate for the Seven Years' War, but there may have been no difference in the achieved effect range because of the quality change to the gunpowder. Light guns may have already been assigned to reduced maximum service charge either 1/3 or 1/4 of the weight of the shot. Here, the 6-pdr and 3-pdr have a charge of 1/4 the weight of the shot.

The point blank point is the point where the shot from a "level" gun first strikes the ground. However, Fortune's numbers appear to be much better matched to a gun at a 1° elevation. Although dated 1778, Fortune is thought to have been a non-commissioned officer in the Royal Artillery whose tables and information best date prior to the regulation changes of 1764. This suggests that although there was a reduction of the maximum service charge in 1764, little range was lost as the gunpowder was more potent. For guns 24-pdr or less, these point blank distances are very similar to the values presented for Effective Range. This is not true for the 42-pdr or 32-pdr where the point bank values were only 1/2 of the effective ranges ― both about 1,200 yards. Comparing range and effectiveness is complicated by the variability in the maximum service charge. During the Seven Years' War, the 42- and 32-pdrs had a maximum service charge of 2/5 the shot weight (40%), not 1/2 (50%) as with most other medium and heavy guns.

Point Blank Range (Fortune 1778, Page 11)
Cannon (iron) 42-pdr 32-pdr 24-pdr 18-pdr 12-pdr 9-pdr 6-pdr 4-pdr 3-pdr
Point Blank Range
(yards)
583 633 650 615 733 716 666 500 400
Point Blank Range
(meters)
533.1 578.8 594.4 562.4 670.3 654.7 609 457.2 365.8

Histories often exaggerate the effective range of cannon. Unless arrayed against a large city, batteries would not be opened several thousand yards from the target — shot from these distances would lose any sense of accuracy. Any number over about 800 yards should be considered in context. If accuracy was required, 600 or 700 yards was a reasonable distance for the furthest batteries. Any required trenching could be started much further away at a safer distance. These distant batteries could be omitted, and the first batteries erected would be much closer. At 400 yards, even light guns would be within effective range. In order to realize maximum shot velocities at impact, breaching batteries would be at 200 yards or closer. Mortars did not suffer from this constraint.

Utmost Range with Major Caution, Easily Abused (Fortune 1778, Page 11)
Cannon (iron) 42-pdr 32-pdr 24-pdr 18-pdr 12-pdr 9-pdr 6-pdr 4-pdr 3-pdr
Utmost Range
(yards)
2,915 3,165 3,250 3,080 3,665 3,580 3,300 2,500 2,000
Utmost Blank Range
(meters)
2,665.5 2,894.1 2,971.8 2,816.4 3.351.3 3,273.6 3,017.5 2,286 1,828.8

Field pieces used fixed ammunition; this was one of their central attributes. Here, the shot and a flannel bag containing the gunpowder were strapped together and stored in ammunition boxes for quick access and loading. During the Seven Years' War and at the extreme upper limits, a British brass field piece could be defined as having:

  1. a barrel weight of less than 2,500 pounds;
  2. gun and carriage weight of less than 4,500 pounds;
  3. gun, carriage and limber weight (without any ammunition boxes) of some 5,200 pounds.

By the Napoleonic Wars, this guideline would be reduced in all three categories ― 2,000 pounds, 4,000 pounds, and 4,700 pounds, respectively. Any further reduction in the weight of the gun plus carriage would be welcomed, the closer to 3,500 pounds the better. In the early 1800s, the reintroduction of the brass 9-pdr (barrel weight of 1,510 pounds) greatly contributed to the effectiveness and maneuverability of the British field artillery. Austria and Prussia had also come to the conclusion that 2,000 pounds was the upper limit on barrel weights for field pieces (both countries having 12-pdr barrels at 1,800 pounds and 6.5 feet in length), but with double-bracketed gun carriages achieving an in-action weight of less than 4,000 pounds was difficult with any of the larger field pieces. France's short 12-pdr (6.5 ft) had a barrel weight of 1,800 pounds (Gribeauval). However, the French long 12-pdr. (7.5 ft) had a barrel weight of 2,200 pounds with a gun plus carriage weight of 4,360 pounds (Wise and Hook 1979, Page 15).

Regarding British artillery, the "long" descriptor is frequently seen in histories. Here, the date of the correspondence needs to be carefully considered. Long may or may not reference heavy pieces. Any "long" Seven Years' War reference is best attributed to heavy pieces. However, "long" is often a reference to brass field pieces designed by Desagulier in the late 1700s, particularly his 3-pdr. and his 6-pdr. These were excellent, well-regarded guns that sized between the 1764 concept for medium and heavy guns. In rough country, Desagulier's 12-pdr was probably too heavy to be classified as a field gun (barrel of 2,490 pounds, 7.5 foot-long), but it was an outstanding battery gun.

The Establishment of 1764 lists some 36 different gun patterns approved for production — many of these would have been Armstrong-Fredrick pattern guns, but others could have been older patterns. Older patterned guns remained in service. In a few instances, the gun weights listed for 1743 and 1764 are identical. Considerable care is needed here — guns of the same lengths in 1743 and 1764 may actually be of different patterns and weights; there is no assumption that they are the same pattern.

Muzzle velocities of British brass field pieces were between 1,500 and 1,700 feet per second. In terms of performance, the brass field guns could be placed in one of two broad groupings (modified from Hughes 1969, Page 77):

  1. Light 12-pdr; light 6-pdr; and heavy 3-pdr.
  2. Medium 12-pdr; heavy 6-pdr; and subsequently, the 9-pdr.

Field Cannon

3-pdr Cannon

The effective range of 3-pdr cannon was between 400 and 600 yards (366 to 549 m.) while their point blank range was 400 yards (366 m.) and their maximum range was approx. 1,200 yards (1,097 m.) at 4°.

Model Barrel
Weight
Barrel
Length
Barrel
Bore
Calibre (Ratio
Length/Shot Diameter)
Shot
Diameter
Charge
Ratio to Weight of Shot
Horses
Light 3-pdr Brass Cannon 280-312 lbs
127-141,5 kg
3.5 ft
106.7 cm
2.913 in
7.4 cm
15 2.775 in
7.05 cm
1/4 n/a
Heavy 3-pdr Brass Cannon 1,230-1,320 lbs
558-599 kg
7 ft
213 cm
2.913 in
7.4 cm
30 2.775 in
7.05 cm
1/4-1/3 4
Heavy 3-pdr Brass Cannon
British Heavy 3-pdr Brass Battering Cannon – Copyright Christian Rogge

The piece illustrated here is depicted on a carriage based on the figures for the heavy guns ‘Travelling Carriages’ found in John Muller, A Treatise of Artillery.

The bracket cheeks are cut from a plank 10 ft long and plain 3 in thick.

The wheels have a diameter of 58 in. Track width of this carriage was 4 ft 8 in.

Note: for a better display, the carriage iron works is illustrated in black. However, the cannon in David Morier painting shows most of the iron works furnished in the same greyish-blue as the wood parts of the carriage.

This ‘heavy’ 3-pdr saw service in all campaigns of the War of the Austrian Succession (1740-48). A detailed record for 1747 can be found in Muller<s book. A total of 26 pieces of this design were fielded in the campaign of 1747 in Flanders. They served with the 14 line infantry regiments as battalion guns during this campaign.

The ‘heavy’ 3-pdr had a regulation allowance of 4 horses, but as Muller notes, more often up to 5 horses were needed for its draught over many poor roads and tracks found in Flanders.

The design of this cannon – a 30 calibre barrel – is much similar to the French long 4-pdr (27 calibre or 219 cm). Also the Austrians fielded a very similar 30 calibre 3-pdr M1717 in the earlier campaigns of the War of the Austrian Succession.

By the period of the Seven Years’ War, the ‘heavy’ 3-pdr piece seems to have been obsolete. All battalions sent to Germany received the new ‘light’ 6-pdrs from the outset. No record of any ‘heavy’ 3-pdr pieces being fielded at any time between 1758 and 1762 in Germany could be found.

6-pdr Cannon

The effective range of 6-pdr cannon was between 500 and 600 yards (457 to 549 m.) while their point blank range was 500 yards (457 m.) and their maximum range was approx. 1,200 yards (1,097 m.) at 4°.

Model Barrel
Weight
Barrel
Length
Barrel
Bore
Calibre (Ratio
Length/Shot Diameter)
Shot
Diameter
Charge
Ratio to Weight of Shot
Horses
Light 6-pdr Brass Cannon 546-560 lbs
248-254 kg
4.5 ft
137.2 cm
3.668 in
9.32 cm
15 3.498 in
8.88 cm
1/4 2 (*)
Medium 6-pdr Brass Cannon 1,160 lbs
526 kg
5 ft
152.4 cm
3.668 in
9.32 cm
17 3.498 in
8.88 cm
1/4-1/3 n/a
Heavy 6-pdr Brass Cannon 2,130-2,160 lbs
966-980 kg
8 ft
243.8 cm
3.668 in
9.32 cm
27 3.498 in
8.88 cm
1/4-1/3 6

(*) For field artillery, Adye (1801) has all 6-pdrs being teamed with a minimum of 4 horses, not two horses.

Light 6-pdr Brass Cannon
British Light 6-pdr Brass Cannon – Copyright Christian Rogge

The light 6-pdr brass cannon was the most commonly used battalion guns.

The piece illustrated here belongs to a series which was first cast around 1745. The carriage of this piece was reconstructed from details given for field carriages in Muller’s book (pp. 112 ff.) and contemporaneous draft originating from the GNM. It should be noted that Muller’s illustration of this field carriage with the iron works on Plate IX contains errors – as he notes himself. It does not show the dimensions of any particular piece. The illustrated dimensions do not fit with any of Muller’s figures listed in his tables. For this reason our illustration stays much closer to the details found in the GNM source. The details Muller provides for this light range of British guns distinctive ‘locker’ and ammunition boxes remain limited. We assume the lower locker would include cassettes for better storage of each shot. The carriage bracket cheek is 7 ft 10 in long. The wheels have a height of 50 inches. Track width is illustrated at 4 ft 8 in.

The greater part of British ordnance fielded in Germany was the light 6-pdr field gun. Each battalion of the British line infantry had two such pieces assigned on campaign. From 1760 on, the two converged grenadier battalions also often received one or two such pieces. The Highlanders were given 1-pdr amusette instead. The light 6-pdr was also employed as light position gun during the campaign of 1759 through 1761. In 1759, two British light brigades of the line were with Ferdinand’s Army, under the command of the captains Drummond and Foy. Each of these brigades consisted of 9 light 6-pdrs. In 1760, the two British light brigades of the line had a mixed ordnance, each with 3 light 6-pdrs, 3 light 12-pdrs and 3 ‘royal’ 5½-in howitzers. For the campaigns of 1761 and 1762, the light 6-pdrs were exclusively used as battalion guns, the 10 pieces previously assigned to the light brigades being all distributed for service with the British Grenadiers and Foot Guards. By 1762, the British contingent operating in Germany had 34 light 6-pdrs.

Light 6-pounder Characteristics in 1776 (Caruana 1977)
Gun barrel 590
Carriage 751
Limber 289
Side boxes  88
Carried Tools and Ropes  83
Ammunition Fixt. 24 rounds 202
Total Weight (lbs) 2,003

Note: Caruana (1977, 72 pages) is a detailed work on the Light 6-pdr dating to 1776. The gun discussed is thought to have a length of 4.5 feet. The carriage is double-bracketed and referenced as old in 1776, suggesting an excellent match for the Seven Years' War. In agreement with Fortune (1778), Caruana clearly states that two horses could draw this weight, but each horse is drawing 1,000 pounds, 650 pounds if the carriage is excluded.

Heavy 6-pdr Brass Cannon
British Heavy 6-pdr Brass Battering Cannon – Copyright Christian Rogge

The piece is mounted on its carriage, the latter illustrated in John Muller A Treatise of Artillery, plates vii and viii. The bracket cheeks illustrated here are cut off from a plank 11 ft 3 in long. The wheels have a diameter of 58 inches. Track width of this carriage was 4 ft 8 in. As per Muller, this being the track width best suited for Flanders – read ‘continental’ Europe.

Note: for a better display, the carriage iron works is illustrated in black. However, the cannon in David Morier painting shows most of the iron works furnished in the same greyish-blue as the wood parts of the carriage.

This ‘heavy’ 6-pdr – often entitled ‘the Long Six’ - saw service in all campaigns of the War of the Austrian Succession (1740-48). Muller records a total of 14 pieces of this design fielded in the campaign of 1747 in Flanders.

It had a regulation draught allowance of 6 horses, but as Muller notes, more often 7 or up to 9 horses were needed for its draught over the many poor roads and tracks found in Flanders.

For the campaigns in Germany during the Seven Years’ War, 8 ‘heavy’ 6-pdrs are first recorded with the British artillery park in winter and spring 1761. The same 8 pieces then went into support of General Granby’s Division in the Battle of Vellinghausen fought on July 15-16. None had been fielded from 1758 through 1760.

The ‘heavy’ 6-pdrs must have arrived from Great Britain in preparation for Ferdinand’s winter offensive in Hesse. A many French strongholds had to be taken, including the fortified city of Kassel. More heavy guns than usual were needed to this end. Also 8 ‘heavy’ 12-pdrs were now with the British artillery for the first time.

9-pdr Cannon

The effective range for a 9-pdr was 900 yards (823 m.) while its point blank range was 716 yards (655 m.).

Model Barrel
Weight
Barrel
Length
Barrel
Bore
Calibre (Ratio
Length/Shot Diameter)
Shot
Diameter
Charge
Ratio to Weight of Shot
Horses
Heavy 9-pdr Brass Cannon 2,910 lbs
1,320 kg
9 ft
274.3 cm
4.2 in
10.67 cm
26 4 in
10.16 cm
1/2 9

12-pdr Cannon

The information around brass 12-pdrs is somewhat chaotic. McConnell includes a medium 6.5-foot brass 12-pdr as part of the 1764 Establishment (Pages 37 and 412), but Caruana does not include this gun in his table. It is thought that this gun was developed around 1750, so its absence from Glegg 1743 is as expected. However, Caruana does include a medium 8.0-foot long brass 12-pdr in the 1764 Establishment, a gun not referenced by McConnell. It could be that the 6.5 ft. gun underperformed and was not included in the 1764 Establishment, but leaning towards McConnell being correct and a typographical error in Caruana. If correct, the medium 12-pdrs at the Battle of Minden (1759) were the 6.5 ft pattern.

The 1,000 pound "light" 12-pdr was made possible by having a barrel length of only 5 feet. The effective range for this piece was 700 yards (640 m.) and its maximum range, 1,400 yards (1,280 m.).

Under the typical noise and dense smoke of a battle, a 12-pdr on a field carriage might fire at an average rate of twice per minute, but if hard pressed, the rate of fire could reach seven shots per minute, but the ammunition stores would then be quickly exhausted.

The effective range of 12-pdr cannon was between 560 and 700 yards (512 to 640 m.) while their point blank range was 733 yards (670 m.) and their maximum range was approx. 1,400 yards (1,280 m.) at 4°.

Model Barrel
Weight
Barrel
Length
Barrel
Bore
Calibre (Ratio
Length/Shot Diameter)
Shot
Diameter
Charge
Ratio to Weight of Shot
Horses
Light 12-pdr Brass Cannon 980 to 998 lbs
444 to 453 kg
5 ft
152,4 cm
4.623 in
11.74 cm
14 4.403 in
11.18 cm
1/4 to 1/3 3 to 5
Medium 12-pdr Brass Cannon 2,408 lbs
1,092 kg
6 ft 7 in
200.6 cm
4.623 in
11.74 cm
18 4.403 in
11.18 cm
1/2 5 to 7
Heavy 12-pdr Brass Cannon 3,250 lbs
1,474 kg
9 ft
274,3 cm
4.623 in
11.74 cm
23.36 4.403 in
11.18 cm
1/2 10


Light 12-pdr Brass Cannon
British Light 12-pdr Brass Cannon – Copyright Christian Rogge

The light 12-pdr brass cannon was the most commonly used field gun. The cannon illustrated here was probably first cast around 1750.

The carriage of this piece was reconstructed with the figures for field carriages found in Muller’s book (pp. 112 ff.). The iron fittings are based on the ones seen in the contemporaneous draft originating from the GNM. The exact dimensions of the locker remain somewhat speculative because the little information Muller provides is insufficient.

The space between the nave of the wheels and the bracket cheek was a few inches less than with the 6-pdr. Obviously, they must have come with other dimensions as the ones timbered for the 6-pdr. The bracket cheek was cut from plank 106 inches long. The wheels have a height of 50 inches. Track width of this carriage is assumed to be 4 ft 8 in.

Four light 12-pdrs were sent to Germany in April 1759. Oddly enough, they were kept in reserve that year, being stored in one of the Allied fortified places. In 1760, six light 12-pdrs were fielded with the two British line artillery brigades under command of the captains Charlton and Stephens – each consisting of 3 light 12-pdrs, 3 light 6-pdrs and 3 ‘royal’ 5½-in howitzers, for a total of 9 pieces each. By June 1761, the light 12-pdrs were down to 4 again (2 believed to be lost in the Combat of Corbach, fought on July 15, 1760). They formed part of the now single British line artillery brigade consisting of 4 light 12-pdrs and 4 5½- in howitzers for a total of 8 pieces, commanded by Captain Carter (Westphalen vol 3-5). The same brigade was also fielded at the beginning of the summer campaign of 1762. It was attached to the right wing of the army during the operations in the vicinity of Wilhelmsthal.

Medium 12-pdr Brass Cannon
British Medium 12-pdr Brass Cannon – Copyright Christian Rogge

By May 1759, ten medium 12-pdrs had been selected to reinforce Ferdinand’s artillery in Germany, according to a letter from Sackville to Ferdinand, dated London February 23, 1759 (Westphalen, vol. Iii, p. 197 – French language). These ten pieces formed a brigade under the command of Captain Forbes McBean during the summer campaign that year. Its commitment in the Battle of Minden, on August 1, played a decisive role in this victory.

For the campaigns from 1760 to 1762, a brigade of 8 such medium 12-pdrs formed part of the British artillery serving in Germany. In the Battle of Vellinghausen, fought on July 15-16, the brigade – now under the command of Captain Foy – went into support of General Granby’s hard pressed troops around the Dinkerberg position.

This piece is mounted on is carriage, according to the figures for the heavy 12-pdrs “Travelling Carriage” found in Muller’s book. As this piece is still rather heavy, a field carriage to mount the light range of ordnance would have been too light a structure for the barrel. Muller does not mention on what particular type of carriage the medium type of ordnance was to be mounted, so we assumed the use of the heavy field carriage. However, the bracket cheeks illustrated here are only 11 ft long – instead of 12 ft. As the medium pieces also received the elevating screw instead of wedges, this carriage does not have a bed transom, but a single largish centre transom onto which the elevating screw was fixed. This also results in a different placement of the two centre bolts. The rear one includes a plate with handling hooks, as it was custom fitting with the travelling carriage of this period. The wheels have a diameter of 58 inches. Track width of this carriage is assumed to be 4 ft 8 in.

The medium brass 12-pdr was far from being easily maneuverable. The combined weight of the barrel, carriage (without ammunition boxes), and limber (without boxes) approached or exceeded 5,000 pounds. In-action, the gun and carriage exceeded 4,000 pounds (double-bracketed carriage). The Napoleonic medium 12-pdr had the same barrel length as that used during the Seven Years' War, but the barrel was some 400 pounds lighter ― an in-action weight of about 3,810 pounds (Hughes 1969, Page 73).

Heavy 12-pdr Brass Cannon
British Heavy 12-pdr Brass Battering Cannon – Copyright Christian Rogge

The heavy 12-pdr brass cannon illustrated here follows General John Armstrong 1736 specification. It is mounted on its carriage, as per John Muller, A Treatise of Artillery.

The muzzle length and the diameter of the muzzle swell are equal to the diameter of the second reinforce ring (85 parts). The bracket cheeks illustrated here are cut off from a plank 12 ft long and 19 in high. The wheels have a diameter of 58 inches. Track width of this carriage was 4 ft 8 in.

Note: for a better display, the carriage iron works is illustrated in black. However, the cannon in David Morier painting shows most of the iron works furnished in the same greyish-blue as the wood parts of the carriage.

On battlefields, the excessive weight of the ‘heavy’ 12-pdr cannon prohibited rapid mobility, but it could be employed in positions were attack was expected. With a barrel weight of nearly two tons, the ability to retreat with this gun was limited. It was not a maneuvering gun and demanded considerable logistical support. The ‘heavy’ 12-pdr was often used in siege settings. In 1757 and 1758, Pitt sent twenty-four ‘heavy’ 12-pdrs to North America for use in campaigns against French Canada.

This ‘heavy’ 12-pdr cannon saw service in all campaigns of the War of the Austrian Succession (1740-48). Muller records a total of 6 pieces of this design fielded in the campaign of 1747 in Flanders.

It had a regulation draught allowance of 10 horses, but as Muller notes, more often up to 15 horses were needed for its draught over the many poor roads and tracks found in Flanders.

For the campaigns in Germany during the Seven Years’ War, there is first record of 8 ‘heavy’ 12-pdrs with the British artillery park in Germany in winter and spring of 1761. The same 8 pieces then went into support of General Conways’s Division in the Battle of Vellinghausen fought on July 15-16. None had been fielded from 1758 through 1760.

The ‘heavy’ 12-pdrs must have arrived from Great Britain in preparation for Ferdinand’s winter offensive in Hesse. A many French strongholds had to be taken, including the fortified city of Kassel. More heavy guns than usual were needed to this end.

Siege and Garrison Cannon

Siege Guns and garrison guns needed to have barrels long enough so that the concussive forces of the firing did not destroy their own embrasures, these were often the longest guns. Muller (1768, Page xvi) advocated that the gun length of siege/garrison guns be at 21 calibers. His recommendation was closely followed (reference Adye 1802, Pages 154 and 155).

18-pdr Brass Cannon (Uncommon Naval or Fortress Gun)

Brass 18-pdrs were not included in the Establishment of 1764.

The effective range of 18-pdr cannon was between 800 and 1,000 yards (732 to 914 m.) while their point blank range was 615 yards (562 m.) and their maximum range was approx. 2,000 yards (1,829 m.) at 7°.

Model Barrel
Weight
Barrel
Length
Barrel
Bore
Calibre (Ratio
Length/Shot Diameter)
Shot
Diameter
Charge
Ratio to Weight of Shot
Horses
Heavy 18-pdr Brass Cannon 5,400 lbs
2,449 kg
9.5 ft
289.6 cm
5.292 in
13.44 cm
22 5.04 in
12.80 cm
1/2 n/a


24-pdr Cannon

The effective range of 24-pdr cannon was between 680 and 850 yards (622 to 777 m.) while their point blank range was 650 yards (594 m.) and their maximum range was approx. 1,700 yards (1,554 m.) at 5°.

Model Barrel
Weight
Barrel
Length
Barrel
Bore
Calibre (Ratio
Length/Shot Diameter)
Shot
Diameter
Charge
Ratio to Weight of Shot
Horses
Light 24-pdr Brass Cannon 1,830 lbs
830 kg
5.5 ft
167.6 cm
5.823 in
14.79 cm
12 5.547 in
14.09 cm
1/3 5
Medium 24-pdr Brass Cannon 4,530 lbs
2,055 kg
8 ft
243.8 cm
5.823 in
14.79 cm
17 5.547 in
14.09 cm
1/2 n/a
Heavy 24-pdr Brass Cannon 5,740 to 5,940 lbs
2,604 to 2,694 kg
9.5 ft
289.6 cm
5.823 in
14.79 cm
20 5.547 in
14.09 cm
1/2 19


Light 24-pdr Brass Cannon

The light brass 24-pdr (barrel weight of 1,830 pounds; 5.5 feet long) was part of the British inventory, but does not seem to have been utilized during the Seven Years’ War ― there is a good chance that this pattern was recognized as understrength. By 1800 and keeping the same barrel weight, the light brass 24-pdr was reduced in length to 5 feet, thus allowing for reinforcement of the breech.

Heavy 24-pdr Brass Cannon
British Heavy 24-pdr Brass Battering Cannon – Copyright Christian Rogge

The barrel of this piece is proportioned according to John Armstrong’s figures provided by David McConnell’s paper. The piece illustrated here is depicted on a carriage based on John Muller’s specifications in his book, A Treatise of Artillery.

The bracket cheeks are cut from a plank 13 ft long and 22 in high.

The wheels have a diameter of 58 in. Track width of this carriage was 4 ft 8 in.

Note: for a better display, the carriage iron works is illustrated in black. However, the cannon in David Morier painting shows most of the iron works furnished in the same greyish-blue as the wood parts of the carriage.

According to the information provided in McConnell’s paper, this ‘heavy’ 24-pdr construction was first recorded by the mid-1730s and continued to be listed with the inventory till well into the Napoleonic period. We found no record to confirm if the British have ever contributed ordnance to any siege train assembled during the War of the Austrian Succession (1740-48) in Flanders or during the Seven Years’ War in Germany, but our research were mainly aimed at British field guns in Germany. Guns of this design were employed at the siege of Belle-Isle in 1761. In 1757 and 1758, Pitt shipped forty-four heavy 24-pdrs to North America for use in campaigns against French Canada.

32-pdr Brass Cannon (Uncommon Naval Gun)

Brass 32-pdrs were not included in the Establishment of 1764.

Model Barrel
Weight
Barrel
Length
Barrel
Bore
Calibre (Ratio
Length/Shot Diameter)
Shot
Diameter
Charge
Ratio to Weight of Shot
Horses
Heavy 32-pdr Brass Cannon 6,220 lbs
2,822 kg
10 ft
304.8 cm
6.410 in
16.28 cm
19.7 6.105 in
15.51 cm
2/5 n/a

42-pdr Brass Cannon (Uncommon Naval Gun)

Model Barrel
Weight
Barrel
Length
Barrel
Bore
Calibre (Ratio
Length/Shot Diameter)
Shot
Diameter
Charge
Ratio to Weight of Shot
Horses
Heavy 42-pdr Brass Cannon 6,830 lbs
3,098 kg
9.5 ft
289.6 cm
7.018 in
17.83 cm
17 6.684 in
16.98 cm
2/5 n/a

References

Adye, Ralph Willet. 1802. The Bombardier and Pocket Gunner. Printed for T. Egerton, Military Library, Whitehall. By W. Blackader, Took's Court, London. Online.

Caruana, Adrain. 1979. British Artillery Ammunition, 1780. Museum Restoration Service. Bloomfield, Ontario.

Caruana, Adrain. 1989. British Artillery Design in British Naval Armaments, ed. Robert D. Smith. Royal Armouries, Conference Proceedings 1. London.

Caruana, Adrain. 1992. Introduction: The Artillerist's Companion 1778 by T. Fortune. Museum Restoration Service. Bloomfield, Ontario.

Cubbison, Douglas R. 2010. The British Defeat of the French in Pennsylvania, 1758: A Military History of the Forbes Campaign Against Fort Duquesne. McFarland & Company, Inc., Jefferson, North Carolina.

Cubbison, Douglas R. 2014. All of Canada in the Hands of the British: General Jeffery Amherst and the 1760 Campaign to Conquer New France. University of Oklahoma Press. Norman.

Cubbison, Douglas R. 2015. On Campaign Against Fort Duquesne: The Braddock and Forbes Expeditions, 1755-1758, through the Experiences of Quartermaster Sir John St. Clair. McFarland & Company, Inc., Jefferson, North Carolina.

Doughty, Arthur George. 1901. The Siege of Quebec and the Battle of the Plains of Abraham; Volume 6: Appendix Part II. Dussalt & Prolux, Quebec.

Duncan, Francis. 1879. History of the Royal Artillery, Volume I, 3rd Edition. John Murray, London. Fortune, T. 1778. The Artilleriʃt's Companion, containing the Diʃcipline, Returns, Pay, Proviʃion, &c. of the Corps, in Field, in Forts, at Sea, &c. Forward by Adrian Caruana. Museum Restoration Service, 1992. Bloomfield, Ontario.

Henry, Chris and Brian Delf. 2002. British Napoleonic Artillery 1793 - 1815 (1): Field Artillery. Osprey Publishing Ltd. Oxford.

Henry, Chris and Brian Delf. 2004. Napoleonic Naval Armaments, 1792-1815. Osprey Publishing Ltd. Oxford.

Hughes, B.P. 1969. British Smooth-Bore Artillery. Stackpole Books, Harrisburg, Pennsylvania. Lavery, Brian. 1987. The Arming and Fitting of English Ships of War, 1600-1815. Conway Maritime Press. London.

Lavery, Brian. 1989. Carronades and Blomefield Guns: Developments in Naval Ordnance, 1778-1805. In: British Naval Armaments; Edited by Robert D. Smith. Royal Armouries, Conference Proceedings 1. London.

McConnell, David. 1988. British Smooth-Bore Artillery: A Technological Study to Support Identification, Acquisition, Restoration. Reproduction, and Interpretation of Artillery at National Historic Parks in Canada. Minister of Supply and Services Canada. Available Online.

Meide, Chuck. 2002. The Development and Design of Brass Ordnance, Sixteenth through Nineteenth Centuries. The College of William and Mary. Online.

Muller, John. 1768. A Treatise of Artillery. John Millan, Whitehall, London. Online. (First edition is 1757, available online as well. Not identical, notable in the Introduction).

O'Callaghan, E. B. 1858. Documents Relative to the Colonial History of the State of New York: Procured in Holland, England and France. Vol. X, Weed Parsons and Company, Printers, Albany. Online. Note: Some written histories will cite these documents as O'Callaghan, but most online sources will have John Romeyn Brodhead as the author per the cover page. O'Callaghan did the editing and translations from the French.

Pargellis, Stanley 1936. Military Affairs in North America, 1748-1765. "MANA". Selected Documents from the Cumberland Papers in Windsor Castle. American Historical Association, 1936. Reprinted: Archon Books, 1969. Online.

Persy, N. 1832. Elementary Treatise on the Forms of Cannon & Various Systems of Artillery. Translated for the use of the Cadets of the U.S. Military Academy from the French of Professor N. Persy of Metz. Museum Restoration Service, 1979.

Westfalen, Christian H. P. elder von. Geschichteder Feldzüge des Herzogs Ferdinand von Braunschweig-Lüneburg, Vol. 5. Berlin 1872, p. 174, 452

Wise, Terence and Richard Hook. 1979. Artillery Equipments of the Napoleonic Wars. Osprey Press. London.

Acknowledgments

Ken Dunne and Christian Rogge for the initial version of this article