The M79 of the 1700s - Hand Mortar

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I shoot mine from the shoulder all the time and I gotta say I don’t notice any bigger ’thump’ than any of my larger cal (75) long barreled muskets with 100-120 grain charges. But assuredly I am only launching tennis balls and not cast iron grenades that weigh a few pounds, LOL!

It is also not a blunderbuss … and technically it is not a cannon either, as it does not have carriage nor wheels.

These actually started out as wheellock ignition hand mortars, to launch grenades over castle or fortification walls.

They went out of favor in military use around the F&I War era due to the horrible fuses they had for the grenades that they launched. One would light the grenade fuse before firing, but in the heat of battle, if you got a flash in the pan, you don’t really know if your firelock went off or not, so they would sometimes explode on the shooter.

There are stories abound that the Grenediers would tie a rope to the mortar and if you had a misfire … you would throw it away from you and get down on the ground as low as you could. Then after it went off, the grenade would blast from the barrel, but if the gun was still shootable, you would pull it back to you and try again. I myself haven’t found anything that says that is historically true or correct.

There were some enterprising individuals that then tried turning the grenade around so that the fuse faced the charge, where it would be lit when the launching charge went off. But again, the fuse technology was so unreliable that the explosion of the charge could force the fuse - now lit! - directly into the explosive grenade … exploding it as soon as it left the barrel. Yikes!
 
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It was discovered that the main charge would ignite the fuse when it was turned away from the powder.
Do you mean from the muzzle blast? What muzzle blast … ?

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I noticed that the grenade was just dropped in, no patch or anything else holding it in. It is possible that the grenade could be flung out of the barrel without tossing the whole gun. Aren't there any surviving grenadier drill manuals from that time that might have addressed it?
 
I think theres an account in ewalds(sp?) Journal of the jaegers using them at charleston in teams, and doing the rope to a stake and the stock wrist thing. The RA didnt want them is my understanding.
 
I shoot mine from the shoulder all the time and I gotta say I don’t notice any bigger ’thump’ than any of my larger cal (75) long barreled muskets with 100-120 grain charges. But assuredly I am only launching tennis balls and not cast iron grenades that weigh a few pounds, LOL!

It is also not a blunderbuss … and technically it is not a cannon either, as it does not have carriage nor wheels.

These actually started out as wheellock ignition hand mortars, to launch grenades over castle or fortification walls.

They went out of favor in military use around the F&I War era due to the horrible fuses they had for the grenades that they launched. One would light the grenade fuse before firing, but in the heat of battle, if you got a flash in the pan, you don’t really know if your firelock went off or not, so they would sometimes explode on the shooter.

There are stories abound that the Grenediers would tie a rope to the mortar and if you had a misfire … you would throw it away from you and get down on the ground as low as you could. Then after it went off, the grenade would blast from the barrel, but if the gun was still shootable, you would pull it back to you and try again. I myself haven’t found anything that says that is historically true or correct.

There were some enterprising individuals that then tried turning the grenade around so that the fuse faced the charge, where it would be lit when the launching charge went off. But again, the fuse technology was so unreliable that the explosion of the charge could force the fuse - now lit! - directly into the explosive grenade … exploding it as soon as it left the barrel. Yikes!
Actually, because these pieces have a chambered breech and the grenade just sits in there, they don't
fit tightly and there is practically no chamber pressure. It doesn't take much powder to throw a 3 lb grenade a long way. Hence the recoil is not unmanageable unless the chamber is overloaded. The windage around the ball was such that fuses could often be simply pulled around the outside of the ball tied in place and face the change for self ignition on firing without the fuse plug itself ever being exposed to the charge.
 
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