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Rebar gunbarrel
- Thread starter Oldmoparguy1
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Well now, that's interesting.
That is pretty cool. When you have melted you last barrel on the zombies I guess. Step up to the new rebar gun barrel.
Wow! I never would have tried that. Takes thinking out of the box to a new level.
That is fantastic.
That's an incredible advertisement for a person's skill and ingenuity.
It's probably not a really good steel for a gunbarrel...but taking something off the work floor and getting the job done rather than buying and blaming blanks is a good show.
It's probably not a really good steel for a gunbarrel...but taking something off the work floor and getting the job done rather than buying and blaming blanks is a good show.
Originally Posted By: DBMaster
I'll give credit to whomever fired the first shot for cajones.
I agree, not knowing the pressure that the barrel can withstand. Still don't know the number of cycles till it fails or will it. I would not want that blowing up in my face. IF it did it would be serious injury. No way would i shoot it , even the 2nd or third time.
I'll give credit to whomever fired the first shot for cajones.
I agree, not knowing the pressure that the barrel can withstand. Still don't know the number of cycles till it fails or will it. I would not want that blowing up in my face. IF it did it would be serious injury. No way would i shoot it , even the 2nd or third time.
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Originally Posted By: Shannow
It's rebar, and quite low carbon, so it will be ductile and relatively immune from fatigue.
It really wouldn't be anything to worry about.
This time I sense the subtle humor. Since rebar is made from melted down mystery scrap, it could be hard or soft or partially this and that, in other words potentially brittle. Anybody rednecking a gun barrel out of rebar is asking for an eyepatch and some mailorder choppers.
It's rebar, and quite low carbon, so it will be ductile and relatively immune from fatigue.
It really wouldn't be anything to worry about.
This time I sense the subtle humor. Since rebar is made from melted down mystery scrap, it could be hard or soft or partially this and that, in other words potentially brittle. Anybody rednecking a gun barrel out of rebar is asking for an eyepatch and some mailorder choppers.
Nope, rebar isn't "junk" steel.
In designing a concrete structure, when in tension, you always have to assume that the concrete is fractured, and the rebar is holding the whole of the load.
In addition, rebar has to be so ductile that it can be bent nearly back on itself to form in the structure...that ductility will protect the shooter from pieces of shrapnel.
It needs to be fairly precise in composition and mechanical parameters...whether scrap was a major source or not, a metallurgist will sample the melt and top up the "additives" accordingly (as an aside, now that cars don't have big chrome bumpers, power station piping is not as good as it once was).
Some specs for 4140
http://www.interlloy.com.au/our-products/high-tensile-steels/4140-high-tensile-steel/
Some specs for weldable rebar (A706)
http://www.portlandbolt.com/technical/specifications/astm-a706/
Carbon
4140 - 0.36 to 0.44%
weldable rebar 0.3
rebar probably doesn't have quite as high a tensile strength, lower hardness, and will bend/erode easier/quicker.
Manganese
4140 - 0.65% to 1.1%
weldable rebar 1.5
rebar will be more ductile and display better fracture toughness.
Chrome
4140 - 0.7 to 1.2
Molybdenum
4140 - 0.15 to 0.35%
weldable rebar - neither mentioned.
4140 will have a higher tensile strength, and better resistance to barrel erosion.
Impurities (sulfur and phosphorous)
4140, 0.04% max of either
rebar, 0.035, 0.045 respectively.
Supposedly the elements that made the Titanic brittle, and remarkably similar.
Mechanical properties.
UTS
4140 (R Heat treat) - 700MPa
weldable rebar - 690MPa
Yield
4140 (R Heat treat) - 525MPa (actually 0.2% proof, rather than yield, as some alloy steels have an ill defined yield).
weldable rebar - 551MPa
Ductility
4140 - 15% elongation
weldable rebar - 12% (in barrel sizes).
Thus my statement that it is likely a very safe stunt.
In designing a concrete structure, when in tension, you always have to assume that the concrete is fractured, and the rebar is holding the whole of the load.
In addition, rebar has to be so ductile that it can be bent nearly back on itself to form in the structure...that ductility will protect the shooter from pieces of shrapnel.
It needs to be fairly precise in composition and mechanical parameters...whether scrap was a major source or not, a metallurgist will sample the melt and top up the "additives" accordingly (as an aside, now that cars don't have big chrome bumpers, power station piping is not as good as it once was).
Some specs for 4140
http://www.interlloy.com.au/our-products/high-tensile-steels/4140-high-tensile-steel/
Some specs for weldable rebar (A706)
http://www.portlandbolt.com/technical/specifications/astm-a706/
Carbon
4140 - 0.36 to 0.44%
weldable rebar 0.3
rebar probably doesn't have quite as high a tensile strength, lower hardness, and will bend/erode easier/quicker.
Manganese
4140 - 0.65% to 1.1%
weldable rebar 1.5
rebar will be more ductile and display better fracture toughness.
Chrome
4140 - 0.7 to 1.2
Molybdenum
4140 - 0.15 to 0.35%
weldable rebar - neither mentioned.
4140 will have a higher tensile strength, and better resistance to barrel erosion.
Impurities (sulfur and phosphorous)
4140, 0.04% max of either
rebar, 0.035, 0.045 respectively.
Supposedly the elements that made the Titanic brittle, and remarkably similar.
Mechanical properties.
UTS
4140 (R Heat treat) - 700MPa
weldable rebar - 690MPa
Yield
4140 (R Heat treat) - 525MPa (actually 0.2% proof, rather than yield, as some alloy steels have an ill defined yield).
weldable rebar - 551MPa
Ductility
4140 - 15% elongation
weldable rebar - 12% (in barrel sizes).
Thus my statement that it is likely a very safe stunt.
Hopefully all the DIY gunsmiths will use superior Australian rebar and not some Chinese or Indian length of discarded rebar from a trash pile. I've see rebar snap while other rebar is very soft. No way you can be sure any random piece of rebar meets quality specs or is suitable for any off-spec use. Where have I heard "it is likely a very safe stunt" before?
Rebar ordered from a supplier should come with a factory certificate with batch strength tests that are done on an accepted statistical basis. Where it is made is irrelevant unless they QA systems aren't up to scratch.
We use glass fibre rebar for ground anchors made in China, and so far so good. Lots of studies done at Canadian universities.
We use glass fibre rebar for ground anchors made in China, and so far so good. Lots of studies done at Canadian universities.
Originally Posted By: crinkles
Rebar ordered from a supplier should come with a factory certificate with batch strength tests that are done on an accepted statistical basis. Where it is made is irrelevant unless they QA systems aren't up to scratch.
We use glass fibre rebar for ground anchors made in China, and so far so good. Lots of studies done at Canadian universities.
In face of those sobering facts I retract my criticism and bow to the collective wisdom of the resident gunsmiths. I must agree that using rebar for making gun barrels is totally safe. All rebar barrels are double stress relieved and meet the required tensile strength of 100,000 pounds per square inch and 25-32 Rockwell hardness, which is typical for gun barrel steel. After all, the Talliban and Mujahedin have made zipguns successfully for a long time, and they are certainly creative and highly skilled experts. Rebar manufacturers will be delighted with increased business from all those DIY gunsmiths. Get reaming!
Rebar ordered from a supplier should come with a factory certificate with batch strength tests that are done on an accepted statistical basis. Where it is made is irrelevant unless they QA systems aren't up to scratch.
We use glass fibre rebar for ground anchors made in China, and so far so good. Lots of studies done at Canadian universities.
In face of those sobering facts I retract my criticism and bow to the collective wisdom of the resident gunsmiths. I must agree that using rebar for making gun barrels is totally safe. All rebar barrels are double stress relieved and meet the required tensile strength of 100,000 pounds per square inch and 25-32 Rockwell hardness, which is typical for gun barrel steel. After all, the Talliban and Mujahedin have made zipguns successfully for a long time, and they are certainly creative and highly skilled experts. Rebar manufacturers will be delighted with increased business from all those DIY gunsmiths. Get reaming!
This idea fascinated me so I spent some time researching it. Nor much info available but I did find 3 more pictures.
Quote:
http://www.assra.com/cgi-bin/yabb/YaBB.pl?num=1313503015/15
singleshotom
Full Member
Posts: 224
Location: tofield
Joined: Feb 23rd, 2008
Re: Bodnar Special Outside Twist RKS Barrel
Reply #17 - Aug 23rd, 2011 at 12:38am Print Post
Thnx Joe for posting as I don't have any pics of the gun myself.
I guess those who know me understand that I love to have fun and think outside the box so to speak.
Ive had this idea of a re-bar barrel for about 20 years and talked my good friend Ron Smith to give it a whirl last winter. Its weldable rebar and that's all I know about it. After drilling and reaming I started to get a good feeling that this might be more then a joke and might even shoot.
It gave Ron a bit of a tough time rifling but looked good. Instead of putting it on a old hywall Ron talked me into trying it on my Yost...... To make a long story short it was a joke that turned out to work so the joke was on me an Ron I guess.
After some breaking in and testing I used it at the Canadian regional's with great success and then planned on the Raton day-view.
I knew most would think it was a crazy idea but knowing how good it shoots I was hoping to do my part and prove it.
The best part of the whole event was my great friend Connie Grims saying " I love it".
Now that's a compliment.
SST
32RKS shooting soft lead bullets in the 1300-1500fps range.
Tom Bodnar was shooting a Yost action. The barrel is chambered for 32RKS shooting a 320 grain bullet. The barrel was rifled by Tom Smith with a gain twist (his signature) but I haven't seen a mention of the actual twist.
here are 3 pics.
http://www.assra.com/yabbfiles/Attachments/DSC_4276.JPG
http://www.assra.com/yabbfiles/Attachments/DSC_4277.JPG
http://www.assra.com/yabbfiles/Attachments/DSC_4278.JPG
Quote:
http://www.assra.com/cgi-bin/yabb/YaBB.pl?num=1313503015/15
singleshotom
Full Member
Posts: 224
Location: tofield
Joined: Feb 23rd, 2008
Re: Bodnar Special Outside Twist RKS Barrel
Reply #17 - Aug 23rd, 2011 at 12:38am Print Post
Thnx Joe for posting as I don't have any pics of the gun myself.
I guess those who know me understand that I love to have fun and think outside the box so to speak.
Ive had this idea of a re-bar barrel for about 20 years and talked my good friend Ron Smith to give it a whirl last winter. Its weldable rebar and that's all I know about it. After drilling and reaming I started to get a good feeling that this might be more then a joke and might even shoot.
It gave Ron a bit of a tough time rifling but looked good. Instead of putting it on a old hywall Ron talked me into trying it on my Yost...... To make a long story short it was a joke that turned out to work so the joke was on me an Ron I guess.
After some breaking in and testing I used it at the Canadian regional's with great success and then planned on the Raton day-view.
I knew most would think it was a crazy idea but knowing how good it shoots I was hoping to do my part and prove it.
The best part of the whole event was my great friend Connie Grims saying " I love it".
Now that's a compliment.
SST
32RKS shooting soft lead bullets in the 1300-1500fps range.
Tom Bodnar was shooting a Yost action. The barrel is chambered for 32RKS shooting a 320 grain bullet. The barrel was rifled by Tom Smith with a gain twist (his signature) but I haven't seen a mention of the actual twist.
here are 3 pics.
http://www.assra.com/yabbfiles/Attachments/DSC_4276.JPG
http://www.assra.com/yabbfiles/Attachments/DSC_4277.JPG
http://www.assra.com/yabbfiles/Attachments/DSC_4278.JPG
The world is full of people doing seemingly absurd things. A large percentage of the time, it's 100% useless. However, every once in a while, a good idea comes along. I'm not sure this one rises into the "useful" category. Seems to me like a waste of time. Kind of like posting on forums...
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