Author Topic: More barrel liner questions (Read 725 times)

entsminger · « **on:** April 28, 2006, 02:50:45 AM »

This is a continuation from another post "new Guy needs Advice" on barrel liners.
From what I'm hearing most typical cannon barrels need a seamless steel liner to make them safe to shoot but large caliber reproduction mortars like 8 and 10 inch 1861 mortars due to the massive wall thickness probably don't need a liner if they are made properly with a newer tougher grade of iron or ductile iron?
I have talked to Hern who make a repro. 8 and and Paulson Brothers who makes an 8 and 10 inch mortar and neither of them use a liner in their mortars and I believe they say the reason is that the wall thickness makes them strong enough so as to not need a liner. I believe Cannons Online would use a liner in a 8 inch mortar if they were to make one but am not clear if they have actually made any yet?
I know that the Fredericksons of Minnesota have made their own 8 and 10 inch mortar and they shoot them all the time and their's do not have liners but they say they used a tougher grade iron than the origional gray iron.
.....So am I correct to assume that these big 8 and 10 inch 1861 mortars don't need liners if made properly?......

I'm also courious about the statement about shooting solid shot being foolish? I just always assumed these big mortars could shoot solid shot or hollow? A friend has found several solid 8 inch cannon ball that we believe were fired from near by mortars. Were they really only capable of throwing hollow shot?
Thanks again
Scott

Cat Whisperer · « **Reply #1 on:** April 28, 2006, 03:09:16 AM »

Not to answer your question directly, but the issue is pressure. Pressure is increased by increasing the mass of the projo, using finer powder and using more powder - to name a few.

What makes the game 'interesting' is that pressure increases very rapidly - exponentially. Knowing what you're doing is the key; coupled with proven safe procedures and practices.

Rickk · « **Reply #2 on:** April 28, 2006, 03:49:40 AM »

Just curious... what did those solid 8 inch balls weigh? Any idea what they are made out of?

entsminger · « **Reply #3 on:** April 28, 2006, 08:27:22 AM »

Well I'm not sure exactly what they weigh as I really haven't held them but they told me they were 100 pounders which probably means they weighed around 60 pounds or so? They are iron. In the good old days I was a relic hunter and found at least 30 cannon balls and projectiles including two 100 pound parrot bolts. Never found any mortar balls but this guy I know seems to have found some lately near me in Arlington Va which were probably fired for test practice by a local civil war fort.
I recently purchased a 15 inch solid shot Rodman cannon ball that could have been fired by a Rodman. It weighs around 450 pounds. Imagine the powder it took to push that!!!
I've gravitated my interest now to actually owning a cannon like a 10 or 8 inch mortar repro. Can't dig them up so will have to win the lottery or something to get one, ha ha....

Scott

Artilleryman · « **Reply #4 on:** April 30, 2006, 02:08:48 PM »

An eight inch mortar shell weighs 45 lbs, eight inch solid shot weighs 65 lbs. It is pointless to fire solid shot from a mortar in combat because you don't get pin point accuracy. The whole idea of firing exploding shells was to keep the enemy's head down while you dug your trenches and gun emplacements closer to their position. Since they would be firing exploding shells that weighs less than solid shot they designed the mortars accordingly.

Eight inch solid shot was used in several different cannons. These cannons could also fire exploding shells.

When I said that it would be foolish to fire (full weight) solid shot from mortars I did so because you would have higher breech pressures and more stress on the mortar trunnions and beds.