The Firing Line Forums - View Single Post - Barrel Re-Thread

HiBC · January 30, 2013, 07:45 AM

Ok,well,it looks like you did a nice job of executing your plan.Good job!

Now,no disrespect intended,I do not mean to rain on your parade.I'm going to give you something to think about.It has to do with safety.I would not take the time to write this over whizzing contest,but it is always OK to speak up over safety.This is about not getting someone hurt.Probably the arteries,nerves and tendons of the left hand.

Barrels are not static,they have harmonics,whip around some,do a tuning fork thing.Take your 12 in scale,hang it over the bench,whack the end of it,watch it vibrate.It curves,whips,spreads out the forces.Put a little notch in your scale,or use a glass cutter on glass,etc,you make a stress riser.A weak spot where all the flex occurs.It fails.

You reduced the wall section around the chamber by about half,yes?So now,the chamber is a smaller diameter,thinner walled tube than designed.The sleeve re-enforces it?Not really.Look at your pix,at the dead sharp corner at the shoulder.That is your stress riser.All the weight of the barrel and vibrations will focus on that corner,and your sleeve does not help it.Maybe it won't fail.I believe in Murphy's law.If it does,the barrel will blow forward,38,000 psi of hot gas and maybe some shards will cut into the inside of someones wrist.

So,my suggestion:You proved you have the skills to get her done!!You just took a wrong turn.

Go back to Wyosmiths muzzle pickle idea.Make the coolest muzzle brake in the world.Make it slip on the muzzle and give it that nice 360 degree full weld.You can get your legal length and the BATF will be happy.I suggest you freebore the muzzle under the weld so any distortion will not affect the bore.

Even 10 in of bore will give a 9mm good ballistics.Barrel length is only a legal requirement.Now,you can set up and cut off your practice job,and make that barrel shank and chamber again with virgin steel,to full original design,and it will never fail,and you will know you did it right.

Just my opinion.Please,understand I'm not in any way trying to put you or your work down!!Keep it up!!

If you have a nice little carbide boring bar,or a Bokum Cobalt,etc,and a chamber drawing,I bet you can bore a fine chamber without a reamer for a 9mm.

January 30, 2013, 07:45 AM	#28
HiBC Senior Member Join Date: November 13, 2006 Posts: 8,288	Ok,well,it looks like you did a nice job of executing your plan.Good job! Now,no disrespect intended,I do not mean to rain on your parade.I'm going to give you something to think about.It has to do with safety.I would not take the time to write this over whizzing contest,but it is always OK to speak up over safety.This is about not getting someone hurt.Probably the arteries,nerves and tendons of the left hand. Barrels are not static,they have harmonics,whip around some,do a tuning fork thing.Take your 12 in scale,hang it over the bench,whack the end of it,watch it vibrate.It curves,whips,spreads out the forces.Put a little notch in your scale,or use a glass cutter on glass,etc,you make a stress riser.A weak spot where all the flex occurs.It fails. You reduced the wall section around the chamber by about half,yes?So now,the chamber is a smaller diameter,thinner walled tube than designed.The sleeve re-enforces it?Not really.Look at your pix,at the dead sharp corner at the shoulder.That is your stress riser.All the weight of the barrel and vibrations will focus on that corner,and your sleeve does not help it.Maybe it won't fail.I believe in Murphy's law.If it does,the barrel will blow forward,38,000 psi of hot gas and maybe some shards will cut into the inside of someones wrist. So,my suggestion:You proved you have the skills to get her done!!You just took a wrong turn. Go back to Wyosmiths muzzle pickle idea.Make the coolest muzzle brake in the world.Make it slip on the muzzle and give it that nice 360 degree full weld.You can get your legal length and the BATF will be happy.I suggest you freebore the muzzle under the weld so any distortion will not affect the bore. Even 10 in of bore will give a 9mm good ballistics.Barrel length is only a legal requirement.Now,you can set up and cut off your practice job,and make that barrel shank and chamber again with virgin steel,to full original design,and it will never fail,and you will know you did it right. Just my opinion.Please,understand I'm not in any way trying to put you or your work down!!Keep it up!! If you have a nice little carbide boring bar,or a Bokum Cobalt,etc,and a chamber drawing,I bet you can bore a fine chamber without a reamer for a 9mm. Last edited by HiBC; January 30, 2013 at 07:50 AM.