Author Topic: Spanish Howitzer Questions (Read 1993 times)

ShooterJK · « **on:** March 25, 2006, 05:56:40 AM »

I like the look of the Spanish Howitzer that Hern's makes but I was wondering if there is anybody out there who makes a machined version with powder chamber. I'm looking for something with a pop can sized bore.

Is anyone on the Forum interested in taking on the project?

Does anyone have any first hand experience with Hern's Spanish Howitzer?

I'd appreciate your comments.

Double D · « **Reply #1 on:** March 25, 2006, 07:10:10 PM »

I beleive there was some issues with Herns method of installing liners. Artlleryman can you comment, I beleive you may have mentioned something about this.

Artilleryman · « **Reply #2 on:** March 26, 2006, 03:27:46 AM »

I believe Hern does not recommend there guns for firing. Look at their website material. Every barrel maker who cast barrels solid and drills and lines them says so, Hern doesn't say how they make theirs. So unless someone comes up with some other information I have to believe that they cast their barrels around a liner.

If you read Matt Switlik's book and articles he has written for the Artilleryman magazine, he points out some problems with this method. First there is the possibility that the liner floats out of position which means that you don't have an equal amount of metal around the bore, and aiming becomes a problem with the barrel pointed one way and the bore liner another. Second there is the possibility that the molten iron melts into the liner or even through it, compromising the strength of the liner. The heat may warp the liner or cause bulges in it which affects accuracy.

Cannon Limited at one time cast around liners. They went to pouring solid and drilling and lining their barrels. Steen and South Bend cast solid and drill and line their barrels. This method is more expensive, but produces a safer barrel. If you think about this as an investment, something that you will have for a long time (most of us till we die) and its resale value plus the safety aspect, it is worth it.

My two cents worth.

dominick · « **Reply #3 on:** March 26, 2006, 11:57:58 AM »

Anyone who has Paul Barnett's catalog (South Bend Replicas) and have seen the photos of the barrel cross sections of many of the barrels he cut apart that were cast around a pipe will know that drilling a solid casting and installing a liner ; machining from a solid piece; or fabricating from heavy wall seamless are the only way to build a barrel properly. Paul's catalog along with Matt Switlik's The More Complete Cannoneer is definitely a worth while investment.

gary michie · « **Reply #4 on:** March 26, 2006, 02:45:17 PM »

Hi
AND out here in the north west the driled tube is a no no because one in oregon blew the liner out of the cast iron barrel. Nothing is 100% I think it all boils down to what you are going to use it for shooten or makeing noise.According to the hoop stress charts for evaluating modern rifle barrrel materials .200" of high quality steel is sufficient to contain 17000 psi (BP discharge).
gary

Artilleryman · « **Reply #5 on:** March 26, 2006, 03:04:13 PM »

Gary, Why did the liner come out?

Double D · « **Reply #6 on:** March 26, 2006, 05:38:43 PM »

I recall some 20 odd years ago when I was shooting in Oregon, there was a liner that came loose durring a shoot and it stuck out the front of the barrel a couple inches. That was when they started requiring lined tubes to have three cap screws

Artilleryman · « **Reply #7 on:** March 27, 2006, 02:22:31 AM »

A vent piece would help also.

Rickk · « **Reply #8 on:** March 27, 2006, 01:57:49 PM »

One of the issues in "The More Complete Cannoneer" reguarding cast-in-place liners is the concentricity of the liner. I don't have any experience with Hern's bigger tubes, but I do have a Hern Coehorn, which is about the same size as the Spanish Howitzer barrel. The liner appears to be pretty much dead center in the bore. I wish I could x-ray it, but they are cracking down on what I sneak into work, and a 92# barrel is hard to hide in my Carhart Jacket pocket.

If anyone was keeping tabs on "Charcoal Burner's" "Mortar in the making", the Hern barrels appear to be at least as sane.

The undrilled vent hole appears to be an attempt at avoiding liablity if anything stupid happens. If I wanted a lawn ornament, I wouldn't have shopped for something with a 1/4 inch steel liner, and a fiberglass make-believe barrel would have cost way less to ship.

For whatever it is worth, Dixie Gun Works drill the vent hole in Hern barrels, resells them, and doubles the price.

Tropico · « **Reply #9 on:** March 27, 2006, 02:23:14 PM »

I have to agree with Rickk here. Again I have full faith in my HERN cannons and it is a liability issue.
After all we have all heard of people pulling "Bozo" stunts.
My 2/3 scale 3" Ordinance Rifles appear to have a straight as bore as anything you can humanly detect and they seem to fire where we aim it and it has taken a "Proofing " by me thats for sure. Considering there is about 48" of pipe in this particular cannon and the cast iron is literally married to it during HERNS pour., I dont think my liners are coming out anytime soon. They are 8" at the breach - 2 1/4 bore that leaves at least a 2 3/4" wall in the blast zone .

Dollar for Dollar a HERN cant be beat., argue any way you want to but HERN hasnt had some record of their barrels coming apart that I am aware of. The larger size cannon makers make some real nice cannons no question about it., however HERN does REAL well on thier guns for alot less money ., no question about that too.

The reason I dont own ALL Hern Guns is because I like Bronze., Stainless., and other metals as well., and a machined piece is awesome. But I dont own other guns because I dont trust a Hern cannon....., I do trust them. I love my Ordinance Rifles !!! :-D

Double D · « **Reply #10 on:** March 27, 2006, 05:33:02 PM »

Quote from: Artilleryman

If you read Matt Switlik's book and articles he has written for the Artilleryman magazine, he points out some problems with this method

First there is the possibility that the liner floats out of position which means that you don't have an equal amount of metal around the bore, and aiming becomes a problem with the barrel pointed one way and the bore liner another.

Second there is the possibility that the molten iron melts into the liner or even through it, compromising the strength of the liner.

The heat may warp the liner or cause bulges in it which affects accuracy.

Cannon Limited at one time cast around liners. They went to pouring solid and drilling and lining their barrels. Steen and South Bend cast solid and drill and line their barrels. This method is more expensive, but produces a safer barrel. If you think about this as an investment, something that you will have for a long time (most of us till we die) and its resale value plus the safety aspect, it is worth it.

My two cents worth.

Read Artilleryman word as a caution

Quote from: Rickk

One of the issues in "The More Complete Cannoneer" reguarding cast-in-place liners is the concentricity of the liner. I don't have any experience with Hern's bigger tubes, but I do have a Hern Coehorn, which is about the same size as the Spanish Howitzer barrel. The liner appears to be pretty much dead center in the bore. I wish I could x-ray it, but they are cracking down on what I sneak into work, and a 92# barrel is hard to hide in my Carhart Jacket pocket.

Again Rick points out the same caution.

If your read and heed the warnings and get a Hern Cannon and you can live with the issues then fine.

Rick have you gone to the X-Ray boss and told him what you would like to do! He may be all for it or may even siggest where you coulld get it done. Post picture...and I won't even nag about high resolution ones of that.

As far as not drilling the vent hole, I ain't no lawyer, but I would be willing to bet the lack of a vent hole by itself is not going to be worth squat in defense of a law suit in a cannon that has a full length bore and you know everyone is converting for live fire..

Rickk · « **Reply #11 on:** March 29, 2006, 07:34:00 AM »

I can get to the XRay machine myself, but they have rules about what I can and can't wander in and out with. It is hard to "sneak" a cannon barrel in without being noticed. I must admit, the company handbook does not specifically address cannon barrels, but if I tried it I am pretty sure there would be a meeting about it and then a handbook revision.... "RULE 76: NO CANNON BARRELS ALLOWED". Imagine someone 20 years from now trying to figure out why that was put in there. I may be persoannly responsbile for 6 or 7 of the rules already, and I am pretty sure that is enough.

As a side note, when you drill the vent hole you are going thru lots of cast iron, followed by the steel seamless liner. I chickened out (fear of breaking the drill) and called in a favor from someone with an EDM machine. I told him where it was supposed to enter the outside, where it was supposed to enter the bore (not a straight line in Hern's mortar barrel by the way), how big a hole I wanted, and 1/2 hour later I had a vent hole. The fixturing to get the angle right was pretty simple for such a short barrel.