Pre bore the chamber results?

[urbanrifleman]

This is why I always establish the chamber first, and then work everything else off of it.

Me too.

I chamber first. Nearly all of my processes are simply in reverse of everyone else's. I can't imagine not cutting the chamber first. First of all, I can cut my chamber until I'm totally satisfied with it. Completely polish it, borescope it, fall in love with it. Then I cut the rest of the barrel around that.

 

[jackieschmidt]

Me too.

I chamber first. Nearly all of my processes are simply in reverse of everyone else's. I can't imagine not cutting the chamber first. First of all, I can cut my chamber until I'm totally satisfied with it. Completely polish it, borescope it, fall in love with it. Then I cut the rest of the barrel around that.

BINGO.

 

[SKWERLZ]

Me too.

I chamber first. Nearly all of my processes are simply in reverse of everyone else's. I can't imagine not cutting the chamber first. First of all, I can cut my chamber until I'm totally satisfied with it. Completely polish it, borescope it, fall in love with it. Then I cut the rest of the barrel around that.

I’ve wondered about that

 

[LVLAaron]

Me too.

I chamber first. Nearly all of my processes are simply in reverse of everyone else's. I can't imagine not cutting the chamber first. First of all, I can cut my chamber until I'm totally satisfied with it. Completely polish it, borescope it, fall in love with it. Then I cut the rest of the barrel around that.

I'd go about it that way if I didn't clock barrels.

 

[Dusty Stevens]

I'd go about it that way if I didn't clock barrels.

Or use the action to set the headspace by feel

 

[urbanrifleman]

Or use the action to set the headspace by feel

You lost me there.

 

[Walt Krafft]

Many of my barrels come with very little extra length. Do it right the first time or cry a LOT.

 

[ridgeway]

I indicate, rough OD, rough ID. Double check inside to make sure she is indicated. Have never had one move so I rarely check. Finish turn OD then bore ID undersize. Thread tenon, then set up to finish ream to depth. Run indicator back inside and let the needle put a smile on your face. Take a peek inside with bore scope and the smile should remain. Cut cone. Cross hatch chamber walls with 320 grit. Polish cone face. Debur leade and end of threads. Saw cut to length. Indicate back in machine to face muzzle with a really sharp tool for a clean burr free cut. Turn tenon for a tuner. Pull out of machine. Spin a fine finish on od with a barrel spinner and belt sander. Set up and engrave. Take to range and hopefully the smile still remains

 

[ISS]

This is why I always bought two reamer sets...

ISS

 

[gaintwist]

I always drill 30 40 under the dia @ the top of the body. bore .005 or 6 under the the shoulder junction, set a zero, and step bore every .4 or .2 less with using the taper of the case before use the reamer. Saves reamer degradation and allows the pilot to pick up first. Final ream take about 5 minutes, max.

Damm.....that is what I have done all on my own. Thanks Alan for making my day.

 

[dakor]

Just going to toss this out there with the whole pre bore thing. So you take a drill bit or twist drill and run it in the bore. You do realize your drill bit is following the bore right? So the hole you just made followed the bore.

Now you take a boring bar and clean the hole up that the bit made and run a reamer in to finish the chamber. How much deflection did that boring bar have in that hole? This is when some one will say I ran a indicator in thee chamber and had zero run out.

Well yeah you used a ridgid setup so your indicartor is going to show no run out. That does not mean your hole is straight because your boring bar had some tool deflection.


So you now have a hole that is not true because you boring bar has tool deflection if you want to admit it or not.

You followed the bore to get to this point and have added multiple steps to a process that does not need to be there and at the end of the day is not going to have any real world effect on accuracy.

 

[LVLAaron]

Sure. Use a sharp tool and take a couple light passes. It'll straighten out.

 

[jackieschmidt]

Just going to toss this out there with the whole pre bore thing. So you take a drill bit or twist drill and run it in the bore. You do realize your drill bit is following the bore right? So the hole you just made followed the bore.

Now you take a boring bar and clean the hole up that the bit made and run a reamer in to finish the chamber. How much deflection did that boring bar have in that hole? This is when some one will say I ran a indicator in thee chamber and had zero run out.

Well yeah you used a ridgid setup so your indicartor is going to show no run out. That does not mean your hole is straight because your boring bar had some tool deflection.


So you now have a hole that is not true because you boring bar has tool deflection if you want to admit it or not.

You followed the bore to get to this point and have added multiple steps to a process that does not need to be there and at the end of the day is not going to have any real world effect on accuracy.

What you just “tossed out there” is a totally false statement that goes against time tested basic machine shop practice.

As a Machinist, I can readily spot falsehoods concerning machine shop practice. However, I’m sure I’m not the only one who read your post and thought….”that’s not right”.

 

[SKWERLZ]

Just going to toss this out there with the whole pre bore thing. So you take a drill bit or twist drill and run it in the bore. You do realize your drill bit is following the bore right? So the hole you just made followed the bore.

Now you take a boring bar and clean the hole up that the bit made and run a reamer in to finish the chamber. How much deflection did that boring bar have in that hole? This is when some one will say I ran a indicator in thee chamber and had zero run out.

Well yeah you used a ridgid setup so your indicartor is going to show no run out. That does not mean your hole is straight because your boring bar had some tool deflection.


So you now have a hole that is not true because you boring bar has tool deflection if you want to admit it or not.

You followed the bore to get to this point and have added multiple steps to a process that does not need to be there and at the end of the day is not going to have any real world effect on accuracy.

Lol!

 

[Carl S]

Just going to toss this out there with the whole pre bore thing. So you take a drill bit or twist drill and run it in the bore. You do realize your drill bit is following the bore right? So the hole you just made followed the bore.

Now you take a boring bar and clean the hole up that the bit made and run a reamer in to finish the chamber. How much deflection did that boring bar have in that hole? This is when some one will say I ran a indicator in thee chamber and had zero run out.

Well yeah you used a ridgid setup so your indicartor is going to show no run out. That does not mean your hole is straight because your boring bar had some tool deflection.


So you now have a hole that is not true because you boring bar has tool deflection if you want to admit it or not.

You followed the bore to get to this point and have added multiple steps to a process that does not need to be there and at the end of the day is not going to have any real world effect on accuracy.

You won't get any tool deflection with a light cut.dont matter what the drill does the boring bar will straighten things up.

 

[dakor]

What you just “tossed out there” is a totally false statement that goes against time tested basic machine shop practice.

As a Machinist, I can readily spot falsehoods concerning machine shop practice. However, I’m sure I’m not the only one who read your post and thought….”that’s not right”.

I have discussed this very topic with a couple machinists one who works on some high level parts.

Both agreed the process is flawed and a waste of time. If you want to pre bore by all means pre bore do what works for you.

If it was the end all be all method why are not all rifle builders using it?

There are many many smiths that are not doing it and their rifles are winning matches.

With the results I see with my rifles on paper I will just stick with running the reamer start to finish.

 

[jackieschmidt]

I have discussed this very topic with a couple machinists one who works on some high level parts.

Both agreed the process is flawed and a waste of time. If you want to pre bore by all means pre bore do what works for you.

If it was the end all be all method why are not all rifle builders using it?

There are many many smiths that are not doing it and their rifles are winning matches.

With the results I see with my rifles on paper I will just stick with running the reamer start to finish.

Well, your machinist friends need to go back to apprentice school. They are just flat wrong.

What Disciplines do you shoot? The satisfaction one has with the performance of their equipment is directly related to the level of precision and accuracy that is required in that Discipline.

 

[LVLAaron]

If it was the end all be all method why are not all rifle builders using it?

Because there are people who think you can't straighten a hole by boring it.

 

[butchlambert]

I have discussed this very topic with a couple machinists one who works on some high level parts.

Both agreed the process is flawed and a waste of time. If you want to pre bore by all means pre bore do what works for you.

If it was the end all be all method why are not all rifle builders using it?

There are many many smiths that are not doing it and their rifles are winning matches.

With the results I see with my rifles on paper I will just stick with running the reamer start to finish.

Young feller, do whatever makes your insides warm and fuzzy. Your so called "machinist" friends need to go back to a basic machining class as Jackie said!

 

[urbanrifleman]

And so the discussion degrades, as the per the usual path...

I think if a man were to only frequent the gunsmithing board on Accurateshooter, I think he might wonder how it is even possible to create a firearm that will hit the broadside of an elephants behind.