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Old 06-08-2023, 10:42 AM   #1
stranger38
 
Join Date: Jan 2009
Location: Indaiatuba/SP Brazil
Default Flintlock Mortar

Good afternoon folks!

Let's try to stat another piece of weaponry. This time, a flintlock mortar

https://www.youtube.com/watch?v=kf9URQ7X0YA&t=141s

Here's the video of Gun Jesus about the gun.

Any ideas?
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Old 06-08-2023, 01:08 PM   #2
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Default Re: Flintlock Mortar

Now that's really interesting .
I recall a Flintlock Cannonette (? possibly another term for Demi-culverin) being posted in a thread years & years ago . May have possibly been 3rd Edition it was so long ago ?
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Last edited by Racer; 06-08-2023 at 01:21 PM.
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Old 06-09-2023, 10:33 AM   #3
Pursuivant
 
Join Date: Apr 2005
Default Re: Flintlock Mortar

From what I've read, Hand Mortars were a somewhat impractical primitive grenade launcher developed in the 17th century and largely abandoned by the 19th century. The idea was that you lit a cast iron hand grenade while simultaneously triggering the mortar. In theory, the muzzle blast tossed the grenade up to 100 yards. They were also used as line and grapnel throwers, fireworks launchers, signal guns and bird-scaring devices. Many were made from cut down surplus musket stocks with a brass cup launcher mounted on the end of the original barrel.

These weapons could generate significant recoil, so despite the shoulder stock they were sometimes fired by bracing the butt against the ground.

3.5" Hand Mortar, FL (c. 1740)
Acc 1 (0 if indirect fired)
Dmg: As per grenade (use stats for Grenade a' Main, High Tech, p. 192) or perhaps 1d cr if the grenade was launched directly at a target.
1/2D: 15 yards
Max: 100 yards
Wgt: 6 lbs.
WPS: 2.05 lbs.
CPS: $10.15
RoF: 1
Shots: 1(10)
ST: 11† (ST8† required if fired braced against the ground).
Bulk: -4
Rcl: 3
Cost: $150?
LC: 3
Malf: 14

Uses Guns/TL5 (Grenade Launcher) if direct firing, Gunner/TL (Mortars) if using indirect fire. Loading time is just the time required to load a powder charge. Placing the grenade in the cup requires a separate Ready action (they were typically placed in the cup just prior to firing). A separate Guns or Gunner skill roll and a Ready action is required to ignite the grenade fuse prior to firing the gun, assuming the gunner has a handy flame source.

Alternately, the shooter can hold the weapon while a second person places the grenade and ignites the fuze.

Because the grenade is held loosely in the cup, holding the gun level requires a DX-2 roll every second to keep it from falling out. It falls out automatically if the gun is angled downwards.

If the gun malfunctions, assume that the grenade fails to ignite prior to being launched on a roll of 14-15. A roll of 16 means the gun misfires, presumably with a lit grenade in the cup! A critical miss inevitably involves the grenade detonating prematurely or falling out of the cup while lit.

The rules above assume a "double ignition." Some grenadiers just placed the unlit grenade with the fuze pointing towards the gun muzzle and relied on the muzzle blast to ignite it. Rules are the same except that no Ready action is required to ignite the grenade, but on a Critical Miss roll 1d. On a 1-3, roll normally. On a 4-6, the fuze is blown into the grenade by the muzzle blast, causing it to detonate just 1d yards from the firer!

Sometime in the late 17th century, some clever person figured out that you could just place the grenade into the cup with the fuze pointing upwards and the muzzle blast would still ignite it. No Ready action is required to ignite the grenade. A roll of 14-15 means the fuze didn't ignite or detonates prematurely at 1d+2 x 10% of the distance to the target. A roll of 16 means the gun misfires. On a Critical Miss roll 1d. On a 1-5 use the normal firearms critical miss table. On a 6, assume that the grenade is lit but remains in the cup or that it detonates prematurely 1d yards from the firer.

If used to hurl a weighted line or grapnel and line, Max is 80 yards. A Ready action is required to place the grapnel/weight. In such cases, Malf is 16, with a roll of 16 indicating a misfire or damage to the line from the muzzle blast.

Note that, since the Hand Mortar was a black powder weapon, the shooter could adjust the powder load to reduce Rcl at the cost of Range (as the shooter in the last You Tube video I referenced does). ST drops to 9 and Rcl drops to 1 if you accept 1/2D 5, Max 50 or ST 10 and Rcl 2 if you accept 1/2D 10, Max 75.

It's also worth noting that black powder shells were notorious for shattering into just a few large pieces. Anyone within shrapnel range is only hit on a 9- on 3d, -1 per yard of distance from the blast.

Crushing damage from a direct grenade is conjectural but is approximately equal to a 2 lb. mass thrown by a man with ST 13-14. I'd have no clue as to how to calculate muzzle velocity given the odd interior ballistics, but it was probably extremely low. In videos you can see the grenade leaving the gun, so probably not more than 100-150 mph.

ST, Rcl, Bulk, Cost, etc. are taken from the Blunderbuss (p. B279). Loading time is roughly based on loading time for a rifle musket and assumes prepared powder charges. Loading with loose powder changes Shots to ~1(15). Wgt is based on the one weight for a historical example that I could find. Max range is based on the data I could find. 1/2D is conjectural, but the grenade is likely to lose a lot of its velocity within the first few yards of light.

Wheelock versions also existed. Treat them as being identical to flintlock versions, but reload time is 1(15) (1/20 with loose powder) due to the need to wind ("span") the lock. They are also vulnerable to all the woes that afflicted other wheelock weapons, such as a tendency for the mainspring to fail if the weapons were kept cocked for long periods of time.

https://en.wikipedia.org/wiki/Hand_mortar
https://www.historynet.com/weapons-check-hand-mortar/
https://www.artic.edu/artworks/11670...and-mortar-gun
https://www.imfdb.org/wiki/Hand_Mortar
https://www.youtube.com/watch?v=n6N2IJccZy4

Last edited by Pursuivant; 06-11-2023 at 07:48 AM.
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Old 10-01-2023, 05:45 PM   #4
stranger38
 
Join Date: Jan 2009
Location: Indaiatuba/SP Brazil
Default Re: Flintlock Mortar

Quote:
Originally Posted by Pursuivant View Post
From what I've read, Hand Mortars were a somewhat impractical primitive grenade launcher developed in the 17th century and largely abandoned by the 19th century. The idea was that you lit a cast iron hand grenade while simultaneously triggering the mortar. In theory, the muzzle blast tossed the grenade up to 100 yards. They were also used as line and grapnel throwers, fireworks launchers, signal guns and bird-scaring devices. Many were made from cut down surplus musket stocks with a brass cup launcher mounted on the end of the original barrel.

These weapons could generate significant recoil, so despite the shoulder stock they were sometimes fired by bracing the butt against the ground.

3.5" Hand Mortar, FL (c. 1740)
Acc 1 (0 if indirect fired)
Dmg: As per grenade (use stats for Grenade a' Main, High Tech, p. 192) or perhaps 1d cr if the grenade was launched directly at a target.
1/2D: 15 yards
Max: 100 yards
Wgt: 6 lbs.
WPS: 2.05 lbs.
CPS: $10.15
RoF: 1
Shots: 1(10)
ST: 11 (ST8 required if fired braced against the ground).
Bulk: -4
Rcl: 3
Cost: $150?
LC: 3
Malf: 14

Uses Guns/TL5 (Grenade Launcher) if direct firing, Gunner/TL (Mortars) if using indirect fire. Loading time is just the time required to load a powder charge. Placing the grenade in the cup requires a separate Ready action (they were typically placed in the cup just prior to firing). A separate Guns or Gunner skill roll and a Ready action is required to ignite the grenade fuse prior to firing the gun, assuming the gunner has a handy flame source.

Alternately, the shooter can hold the weapon while a second person places the grenade and ignites the fuze.

Because the grenade is held loosely in the cup, holding the gun level requires a DX-2 roll every second to keep it from falling out. It falls out automatically if the gun is angled downwards.

If the gun malfunctions, assume that the grenade fails to ignite prior to being launched on a roll of 14-15. A roll of 16 means the gun misfires, presumably with a lit grenade in the cup! A critical miss inevitably involves the grenade detonating prematurely or falling out of the cup while lit.

The rules above assume a "double ignition." Some grenadiers just placed the unlit grenade with the fuze pointing towards the gun muzzle and relied on the muzzle blast to ignite it. Rules are the same except that no Ready action is required to ignite the grenade, but on a Critical Miss roll 1d. On a 1-3, roll normally. On a 4-6, the fuze is blown into the grenade by the muzzle blast, causing it to detonate just 1d yards from the firer!

Sometime in the late 17th century, some clever person figured out that you could just place the grenade into the cup with the fuze pointing upwards and the muzzle blast would still ignite it. No Ready action is required to ignite the grenade. A roll of 14-15 means the fuze didn't ignite or detonates prematurely at 1d+2 x 10% of the distance to the target. A roll of 16 means the gun misfires. On a Critical Miss roll 1d. On a 1-5 use the normal firearms critical miss table. On a 6, assume that the grenade is lit but remains in the cup or that it detonates prematurely 1d yards from the firer.

If used to hurl a weighted line or grapnel and line, Max is 80 yards. A Ready action is required to place the grapnel/weight. In such cases, Malf is 16, with a roll of 16 indicating a misfire or damage to the line from the muzzle blast.

Note that, since the Hand Mortar was a black powder weapon, the shooter could adjust the powder load to reduce Rcl at the cost of Range (as the shooter in the last You Tube video I referenced does). ST drops to 9 and Rcl drops to 1 if you accept 1/2D 5, Max 50 or ST 10 and Rcl 2 if you accept 1/2D 10, Max 75.

It's also worth noting that black powder shells were notorious for shattering into just a few large pieces. Anyone within shrapnel range is only hit on a 9- on 3d, -1 per yard of distance from the blast.

Crushing damage from a direct grenade is conjectural but is approximately equal to a 2 lb. mass thrown by a man with ST 13-14. I'd have no clue as to how to calculate muzzle velocity given the odd interior ballistics, but it was probably extremely low. In videos you can see the grenade leaving the gun, so probably not more than 100-150 mph.

ST, Rcl, Bulk, Cost, etc. are taken from the Blunderbuss (p. B279). Loading time is roughly based on loading time for a rifle musket and assumes prepared powder charges. Loading with loose powder changes Shots to ~1(15). Wgt is based on the one weight for a historical example that I could find. Max range is based on the data I could find. 1/2D is conjectural, but the grenade is likely to lose a lot of its velocity within the first few yards of light.

Wheelock versions also existed. Treat them as being identical to flintlock versions, but reload time is 1(15) (1/20 with loose powder) due to the need to wind ("span") the lock. They are also vulnerable to all the woes that afflicted other wheelock weapons, such as a tendency for the mainspring to fail if the weapons were kept cocked for long periods of time.

https://en.wikipedia.org/wiki/Hand_mortar
https://www.historynet.com/weapons-check-hand-mortar/
https://www.artic.edu/artworks/11670...and-mortar-gun
https://www.imfdb.org/wiki/Hand_Mortar
https://www.youtube.com/watch?v=n6N2IJccZy4

very nice! thanks a lot
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Old 10-01-2023, 09:08 PM   #5
Fred Brackin
 
Join Date: Aug 2007
Default Re: Flintlock Mortar

Quote:
Originally Posted by Pursuivant View Post
From what I've read, Hand Mortars were a somewhat impractical primitive grenade launcher l]
The original 3e versions of High Tech were rich in odd sorts of guns like this. I believe it covered not only "cup" grenade launchers but also "rod grenades" to could be used with regular smoothbores.

Note that cup launchers for rifle grenades which appeared in WWI for smokeless powder guns were just a new version of these.

If pdfs of 3e versions of HT are available they might be worth the OPs trouble.
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Old 10-01-2023, 09:27 PM   #6
Polydamas
 
Join Date: Jan 2006
Location: Central Europe
Default Re: Flintlock Mortar

Quote:
Originally Posted by Pursuivant View Post
Because the grenade is held loosely in the cup, holding the gun level requires a DX-2 roll every second to keep it from falling out. It falls out automatically if the gun is angled downwards.
is that based on a period source? If its from modern experience, I expect there were period solutions that your source has not yet figured out, such as putting a cloth wad in front of the grenade. Tod the Cutler has found that its easy to shoot downwards with a medieval European type crossbow by just resting the thumb on the butt of the bolt, it seems like the string or the nut might catch your thumb but it does not actually.

Edit: in addition, you would need to define 'holding the gun level' in game terms. Is an Aim or Wait maneuvre within 1/2 D 'holding the gun level'?
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Last edited by Polydamas; 10-01-2023 at 09:51 PM.
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Old 10-01-2023, 09:27 PM   #7
stranger38
 
Join Date: Jan 2009
Location: Indaiatuba/SP Brazil
Default Re: Flintlock Mortar

Quote:
Originally Posted by Fred Brackin View Post
The original 3e versions of High Tech were rich in odd sorts of guns like this. I believe it covered not only "cup" grenade launchers but also "rod grenades" to could be used with regular smoothbores.

Note that cup launchers for rifle grenades which appeared in WWI for smokeless powder guns were just a new version of these.

If pdfs of 3e versions of HT are available they might be worth the OPs trouble.
I'll take a look. Try to convert to 4e
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Old 10-01-2023, 10:14 PM   #8
Fred Brackin
 
Join Date: Aug 2007
Default Re: Flintlock Mortar

Quote:
Originally Posted by stranger38 View Post
I'll take a look. Try to convert to 4e
Damage doesn't need converting.

You might get somewhat different 1/2D and Max ranges if you could find all the data Doug Cole's spreadsheet needs but Ve2 will give you numbers and it isn't really a critical stat in 3e or 4e.

ACC you don't convert mathematically. 4e has only a few AC figures and you take out the 3e number and replace it with the 4e number for that format of gun.

Rcl can be tricky. Especially as they are effectively different stat going from3e to 4e. This could be another case of "use a 4e looking number".

Weight of gun and ammo are in real world numbers and should be okay as is. If available you can simply use Real World figures for the weapon you're tryign to stat.
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Old 10-01-2023, 10:55 PM   #9
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Default Re: Flintlock Mortar

Quote:
Originally Posted by Fred Brackin View Post
ACC you don't convert mathematically. 4e has only a few AC figures and you take out the 3e number and replace it with the 4e number for that format of gun.
4e Acc is usually about half of 3e Acc. It's the general philosophy of 4e that the basic rules should assume stress and give a bonus for non-stressful conditions, while 3e had an optional rule to halve Acc under stressful conditions.
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Old 10-02-2023, 01:24 AM   #10
Fred Brackin
 
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Default Re: Flintlock Mortar

Quote:
Originally Posted by RyanW View Post
4e Acc is usually about half of 3e Acc. It's the general philosophy of 4e that the basic rules should assume stress and give a bonus for non-stressful conditions, while 3e had an optional rule to halve Acc under stressful conditions.
I think that's coincidence. Look at the Laser and Blaster Design article in Pyramid 3/37. There ACC is simply assigned by type of weapon and the way people use it. For Lasers all holdouts are ACC 3, pistols are AC 6, rifles are ACC 12 and support weapons are ACC 18.

No calculations at all relative to 3e stats or any 4e stuff.
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