The Imperial Brazilian ironclads were armed with the following guns:
- 120-pounder Whitworth rifled muzzle-loading cannon
- 70-pounder Whitworth rifled muzzle-loading cannon
- 68-pounder smoothbore muzzle-loading cannon
- 12-pounder smoothbore muzzle-loading cannon
120-pounder Whitworth rifled muzzle-loading cannon
This was a rifled muzzle-loader that had a Whitworth hexagonal rifled bore.
A drawing of Joseph Whitworth's hexagonal polygonal gun bore and projectile. It was used in weapons ranging from infantry rifles up to 120-pounder cannons.
- Weight: 16,660 pounds (7,556.8 kg)
- Length 144 inches (3.658 m)
- Projectiles: Shell; Solid shot; Explosive shell
- Shell weight: 151 pounds (68.5 kg)
- Calibre: 7-inch (178 mm)
- Maximum range: 5,540 yards (5,070 m)
Research indicates that the Imperial Brazilian Navy was the only purchaser of this cannon.
70-pounder Whitworth rifled muzzle-loading cannon
This was a rifled muzzle-loader that had a Whitworth hexagonal rifled bore.
- Weight: 8,582 pounds (3,892.7 kg)
- Length 118 inches (2,997 m)
- Projectiles: Shell; Solid shot; Explosive shell
- Shell weight: 81 pounds (36.7 kg)
- Calibre: 5.5-inch (140 mm)
- Maximum range: 5,540 yards (5,070 m)
Four of these cannons were seized by the United States Navy on 29th January 1863 when the blockade-runner Princess Royal was captured by the USS Unadilla and the USS G W Blunt.
68-pounder smoothbore muzzle-loading cannon
A 68-pounder smoothbore muzzle-loading cannon. This example used to be on display outside the former Royal Artillery Museum at the Rotunda, Woolwich.
- Weight: 88 cwt/9,856 pounds (4,470.606 kg), 95 cwt/10,640 pounds (4,826.223 kg), 112 cwt/12,544 pounds (5698.863 kg)
- Length: 88 cwt: 9 feet 6 inches (2,896 mm); 95 cwt: 10 feet (3,048 mm); 112 cwt: 10 feet 10 inches (3,302 mm)
- Projectiles: Solid shot; Explosive shell
- Shell weight: 68 pounds (30.84 kg)
- Calibre: 8.12 inches (20.62 cm)
- Maximum range: 3,620 yards (3,310 m)
12-pounder smoothbore muzzle-loading cannon
By 1860, the 12-pounder smoothbore muzzle-loading cannon was obsolete.
- Weight: 32 cwt/1,626 pounds (736.541 kg)
- Length: 9 feet (274 mm)
- Projectiles: Solid shot; Explosive shell
- Shell weight: 9 pounds (4.1 kg)
- Calibre: 4.623 inches inches (11.74 cm)
- Maximum range: 1,800 yards (1,610 m)
Bob -
ReplyDeleteI gather that the Whitworth rifles - small arms or ordnance - were phenomenally accurate. The Confederates armed a small number of snipers with Whitworth rifled muskets (an equal number had Blakelys, I think) with telescoping sights. I gather one of them got Major-General John Sedgwick at Spotsylvania Court House at over 1000 yards.
Legend has it that General Bayard was cut in two by a muzzle-loaded Whitworth artillery piece at the range of over a mile, whilst riding along a road. It happened that the cannon was aligned along that stretch of road, and Bayard was riding directly away from the piece.
I gather that the type's usefulness was impaired by the unsatisfactory effect of the explosive shell. The shape of the projectile rather limited the quantity of explosive charge that could be contained therein.
In my ACW armies, I have permitted the CSA precisely one muzzle-loading Whitworth cannon (a simple adaptation of an Airfix piece). Research indicates the Confederacy never received (probably never ordered, supposing they were in fact available) any breech-loading examples.
Cheers,
Ion
Cheers,
Ion
Archduke Piccolo (Ion),
DeleteThe concept of the hexagonal bore has always seemed to me to be one of those dead ends in armament design. Whilst it worked, making the ammunition, rifling the guns, and loading the ammunition into the gun were all complex, and although it enabled very accurate long distance shooting, one wonders how well the weapons would have performed longterm.
When they trialled the 1,5-inch calibre Whitworth cannon at Woolwich, they set up a target at 1,000 yards. The first round hit the centre of the target, went through it, and then they ‘lost’ it. Story has it that it went well over three times the expected range!
Incidentally, the Blakely cannons were manufactured at the Blakely Gun Foundry at Ordnance Wharf on Greenwich Peninsular. This was close to the Bessemer Steel Works, who provided the steel from which the cannons were cast.
All the best,
Bob
Some notes: all 68 pdr guns used in Brazilian ironclads were 68 pdr 95 cwt, named as "68 pdr 1st class", the 88 cwt gun was named as "2nd class" and armed some of the larger wooden warships. You put the data for the Whitworth 150 pdr gun, which has exactly the same caliber than the 120 pdr, but was reinforced and shot a longer, heavier projectile. Some ironclads were armed with 150 pdrs, but not all, although all were classified as 120 pdrs (Today, the gun from the Monitor Piauhy is preserved at Ladário Naval base, and it is a 150 pdr). The maximum range of the 120 pdr, by Brazilian army/navy manuals was 3735 meters with 11o degrees elevation, the maximum range of the 150 pdr was 4841 meters with 14o degrees elevation, thought there are other sources that give the range of the 120 pdr as 5580 meters with 15o elevation (and the 70 pdr 5.550 meters with the same elevation). The other data also does not reflect what is written in Brazilian army/navy manuals. The 12 pdr mentioned in ships lists is not a long gun, but a copy of the French 1829 mountain howitzer, like the American mountain howitzer of 1842 and was used as boat/landing gun. The only instance of this gun being used in riverine combat was in the battle of Riachuelo, when the army 9th Infantry Battalion being carried on board of the Araguari corvette maned two pieces in combat. All large ironclads had this gun for its boats (one or two on board), but these were not used in combat, as there was not surplus crew to man those during a combat, only as boat guns, in which role some were used against the Paraguayan forces surrounded in the swampy Chaco region, after the fall of Humaitá fortress.
ReplyDeleteAdler Homero,
DeleteThank you very much for such useful information. I had to use a number of secondary sources to get the information that I included in my blog post … and had to try to pick my way through conflicting data.
Whitworth guns were mainly manufactured in Manchester, and I used archives that I could access. I was also able to do some research using archives that relate to the Woolwich Arsenal - where several Whitworth guns were tested - which is about a mile from my home. (There is a local road that is names after Whitworth to commemorate the link between Woolwich and Whitworth.)
All the best,
Bob
I did not mean my comment as a criticism, indeed I congratulate you in your efforts: I realize that most people do not have access to obscure sources on artillery, specially written in Portuguese, my intention was only to clarify a topic that is obscure even in Brazil. To complement my notes: though it does not appear in ship armament sources, the 12 pdr boat howitzer was partially substituted during the war, first by a 1 pounder Whitworth, then, after 1868, after Brazil signed the Saint Petersburg treaty (during a war!) by a 2 and 2 and a half pounder Whitworths. The Whitworths were especially important in Brazil, as it was the main gun in the navy, from 1874 to 1883, the Navy buying pieces of up to 12 inches – 600 pdr (that were destined to arm the ill fated Independência, but this after the war).
DeleteAdler Homero,
DeleteMay I thank you again for your excellent information, which I found very, very useful. I certainly did not regard your comment as criticism … and hope to incorporate it in any future blog posts that I write about this topic.
You might be interested to know that I created a YouTube video about the Brazilian ironclads. My channel shares the same name as my blog, and the video is based on a blog post that I created some time ago.
All the best,
Bob