RiflingBob
Plastic
- Joined
- Jun 30, 2019
So i want to make a very simple barrel(no lugs/no different diameters across the length), basically just a cylinder that is let's say 145mm long.
I have a 23mm diameter 9x19mm barrel blank and it is 550mm in length.
Now do these following operations make sense to you ?
If not please correct me, if yes please confirm that my steps are correct in theory.
1. I take the barrel blank and put it into my chuck in the spindle and the other end stays free, but since the barrel blank is so long i'll use a steady rest on the other end.(my spindle bore is too small to have the majority of the barrel blank stay at the spindle end of the lathe)
2. I now cut a little bit longer than 145mm piece of the barrel blank off with a parting tool, I use cutting fluid and slowly but steadily cut into the blank so that a 145mm piece of the barrel blank almost falls off. I use a hand saw to cut the last bit off.
3. FIRST QUESTION: Now here is a question i have at this step: Do i have to cut a 60° chamfer into both ends of this barrel blank piece before i can work it between centers ? If yes does that mean i will then have to mount the left end into the chuck in the spindle and with the help of a steady rest on the right, i then drive the 60° chamfer mill head which i have mounted in the tailstock, into one end of the barrel, then i take out the barrel, turn it around, and add a chamfer on the other side as well ?
4. Now take the chuck out of my spindle and replace it with a in my case mt3 tapered dead center, use a threaded hole at the spindle to screw in a screw, butt end of the barrel against the dead center and now use a lathe dog that i secure around the barrel and which butts against the screw that is mounted around the spindle.
5. I put a live center into the tailstock, in my case with a mt2 taper.
6. I use a dial indicator to make sure that the centers run true, if not look if cleaning the taper hole, and putting them in again, helps.
7. I now put the barrel between the centers and can now turn down the barrel to my desired OD.
8. Now that my desired OD has been reached, i take out the spindle center and put in the chuck again
9. I put the majority of the barrel through the spindle, since the OD does fit through the spindle bore now and mount it, making sure the dial indicator says the barrel runs true to center when the spindle rotates.
10. QUESTION: Now here comes another question that i have, would you recommend i use a boring bar now to pre bore the chamber 0.010” undersize or not ?
11. I then take out the barrel and mount it into a vise with the muzzle end pointing to the floor and ream the chamber carefully with a tap and a 9x19mm finishing reamer ( i don't have the tools to mount the reamer properly into my tailstock( like a floating reamer holder).
12. Now i'm basically done and can add things like turning a section at the muzzle end down so i can thread the muzzle and also, in my case, add a chamfer to the chamber side for the cartridge to go into the chamber properly, which i need for my specific gun design the barrel is intended for.
I have a 23mm diameter 9x19mm barrel blank and it is 550mm in length.
Now do these following operations make sense to you ?
If not please correct me, if yes please confirm that my steps are correct in theory.
1. I take the barrel blank and put it into my chuck in the spindle and the other end stays free, but since the barrel blank is so long i'll use a steady rest on the other end.(my spindle bore is too small to have the majority of the barrel blank stay at the spindle end of the lathe)
2. I now cut a little bit longer than 145mm piece of the barrel blank off with a parting tool, I use cutting fluid and slowly but steadily cut into the blank so that a 145mm piece of the barrel blank almost falls off. I use a hand saw to cut the last bit off.
3. FIRST QUESTION: Now here is a question i have at this step: Do i have to cut a 60° chamfer into both ends of this barrel blank piece before i can work it between centers ? If yes does that mean i will then have to mount the left end into the chuck in the spindle and with the help of a steady rest on the right, i then drive the 60° chamfer mill head which i have mounted in the tailstock, into one end of the barrel, then i take out the barrel, turn it around, and add a chamfer on the other side as well ?
4. Now take the chuck out of my spindle and replace it with a in my case mt3 tapered dead center, use a threaded hole at the spindle to screw in a screw, butt end of the barrel against the dead center and now use a lathe dog that i secure around the barrel and which butts against the screw that is mounted around the spindle.
5. I put a live center into the tailstock, in my case with a mt2 taper.
6. I use a dial indicator to make sure that the centers run true, if not look if cleaning the taper hole, and putting them in again, helps.
7. I now put the barrel between the centers and can now turn down the barrel to my desired OD.
8. Now that my desired OD has been reached, i take out the spindle center and put in the chuck again
9. I put the majority of the barrel through the spindle, since the OD does fit through the spindle bore now and mount it, making sure the dial indicator says the barrel runs true to center when the spindle rotates.
10. QUESTION: Now here comes another question that i have, would you recommend i use a boring bar now to pre bore the chamber 0.010” undersize or not ?
11. I then take out the barrel and mount it into a vise with the muzzle end pointing to the floor and ream the chamber carefully with a tap and a 9x19mm finishing reamer ( i don't have the tools to mount the reamer properly into my tailstock( like a floating reamer holder).
12. Now i'm basically done and can add things like turning a section at the muzzle end down so i can thread the muzzle and also, in my case, add a chamfer to the chamber side for the cartridge to go into the chamber properly, which i need for my specific gun design the barrel is intended for.