Reamer Pusher

[Judd]

I've never felt like it was in anyway dangerous. I have my hand on the reamer holder at all times for the tactile feedback. If I crowd the reamer too much it will spin. My hand is not on the reamer flutes and even if it was the cutting edge is on the trailing side.

It’s not the reamer that concerns me it’s die/reamer holder pinching or pinning my hand against the compound. You combat that by your piece on your tool post.

 

[DaveTooley]

Nate from Straight Shot Gunsmithing (TBAS chucks) does just that on his TL-1. He used to sell a ready made gang tool holder for the TL-1. He also uses a fully adjustable but rigid reamer holder. Phil aka 4Mesh used to do complete CNC chambers. I believe at one point he said he had never used a chamber reamer in the CNC to chamber his barrels. He made his own custom toolholders that used Circle inserts. He was quite successful in his short time in the 1K BR world. Nate from Straight Shot also at one time was working on total CNC's chambers with custom tooling but I think he gave that up. Chad Dixon aka NesikaChad proprietor of Long Rifles Inc I believe roughed chambers CNC. I remember all of the naysayers that told Chad he was destined to fail with the CNC gunsmithing thing

I remember Phil. Shot with him in VA. He had custom carbide boring bars made in Switzerland.

 

[xr650rRider]

The other pondering I now have is most tailstocks have some play in the quill so who’s to say mine doesn’t center up a couple of thousandths under load when pushing on the reamer???

Put a DTI on it and measure it.

 

[xr650rRider]

Who has the most record setting chamber jobs? All that matters is at the target.

 

[DaveTooley]

It’s not the reamer that concerns me it’s die/reamer holder pinching or pinning my hand against the compound. You combat that by your piece on your tool post.

The rotational force isn't high. I could easily hold just the case holder and cut a chamber. Sometimes when I'm a bit short on HS I insert the reamer and holding everything in my hand, rotate the spider by hand to finish the cut.

 

[WSnyder]

Put a DTI on it and measure it.

No real need, it just works as is!

How does it work? It just does!

All kidding aside, I know it moves. Everything moves especially on old manual machines.

 

[Judd]

Also…fwiw…while looking today, PTG has the bald eagle eligible for back order.

 

[tobnpr]

Put a DTI on it and measure it.

Yup.
For those of us working with older machines that've seen "some use", precise tailstock alignment is challenging. They're designed to be intentionally high when new as noted here to allow for wear.
And wear they will. Even with hardened ways, the tailstock base ain't (nor is the saddle) and it will wear- and not evenly. Because of chips, and forward pressure sliding it the base wears more towards the front, you end up with uneven wear with a tilt downwards towards the headstock.

So, insert shims between the base and body front/back to get it to correct height and "even" front to back.
Problem solved...not. You've still got the wear in the bed- granted, usually minimal on the tailstock ways depending on how much the tailstock was used, and where on the bed. So, you need to shim and indicate at a specific location on the bed because it will vary any where else you place it.

Then there's the quill itself...

Fortunately, there's no machining I do that requires absolutely precise tailstock alignment. That's why we have floating holders for taps and reamers, and boring bars to get those holes perfectly concentric before using them

 

[DaveTooley]

No real need, it just works as is!

How does it work? It just does!

I've been thinking about your process. Anything going into a hole wants to center up. You give the reamer enough travel to, if needed, to center up.

 

[Edd]

Cool. If the stars align, and WW3 doesn't start, I'll be able to retire in a couple of years... at which point I can take the gun plumbing a little more seriously.

WW3 is already in progress.

 

[STS]

My pusher is as follows.
1. Morse taper drill chuck arbor, held with a MT 3/5 adapter in the spindle and center drilled, drilled, then bored to .020 over reamer shank and faced square.
2. Old first generation Sinclair neck turner case holder with handle extension, clamped to a turned 7/16 spud then faced on one side.
3. Predrill and taper bore chamber to just under shoulder diameter. The reamer will set nicely in line with the chamber when getting ready for a cut. Nice on size chambers that are well centered with near zero runout.

 

[Carl S]

If I drill a 1/4" pilot hole
then take a 3/8" drill bit and start drilling the next step up with the base of the drill bit skewed 3 degrees off .......................................................................................................................................................................................
You're saying it'll come out just fine ?
Because the initial pilot hole that was dead true

As long as you finish with a boring bar after drilling,you should be just fine.

 

[JFrank]

Ensuring the dead center is inline and coupled with pre boring, pushing seems like a sound approach compared to a floating reamer holder that by shear definition might add one additional layer of complexity.

 

[tobnpr]

Ensuring the dead center is inline and coupled with pre boring, pushing seems like a sound approach compared to a floating reamer holder that by shear definition might add one additional layer of complexity.

Distinction without a difference far as I can tell.
Manson's floating holder is two machined "floating" flats that allow for radial float same as any pusher design I've seen.

I don't see how any pusher design can effectively deal with axial float without it trying to force the reamer off center, if there is one I'd ♥ to see it.

 

[Alex Wheeler]

Cutting a chamber without runout is pretty simple, most methods will do this. The lathe "wants" to do that. You would have to fight it to get any substantial runout. What you really should care about is throats that are centered exactly and chambers that are on size. Poor setups cut fat chambers that are still runout free.

 

[LVLAaron]

^^ I did some barrels for a guy- he complained that they were super tight and wouldn't extract, had to beat the handle with a hammer. Same reamer his old guy used. Must be my fault so he brings it over. I make him bring his reamer print. He's got a tight reamer (308) with a .470 200 line. Old guy cut round chambers but were definitely oversized.

Even when you do things right, the phone still rings.

 

[WSnyder]

He's got a tight reamer (308) with a .470 200 line.

Not a 95 Palma by chance? I have one, it's great for SA mag length but the .470" @ .200" is definitely too tight. I open them up a few at the back.

 

[ELR LVR]

The reamer acts like a boring bar It doesn’t take the hole out of concentricity it just cuts bigger than the reamer was designed to cut Since most cartridges are tapered bodies, as long as you switch to the pusher before you finish the chamber the reamer will follow the prebored hole and cut on size.

I understand
But before that
How much of an enlarged chamber was it cutting?
and how do you know youve cut away the ENLARGED portion once switching over to pushing the reamer

 

[Alex Wheeler]

^^ I did some barrels for a guy- he complained that they were super tight and wouldn't extract, had to beat the handle with a hammer. Same reamer his old guy used. Must be my fault so he brings it over. I make him bring his reamer print. He's got a tight reamer (308) with a .470 200 line. Old guy cut round chambers but were definitely oversized.

Even when you do things right, the phone still rings.

But after you explain why, your phone rings for many years. If it doesnt your in trouble.

 

[ELR LVR]

It’s not the reamer that concerns me it’s die/reamer holder pinching or pinning my hand against the compound. You combat that by your piece on your tool post.

I do it this way,
I like to feel the toolholder pinch my hand against the compound table
it doesnt really "PINCH" more than put pressure against your hand
by doing it this way
I can very well monitor how much tool pressure I am placing on the reamer as it feeds
as well as feel for hard spots it may be cutting through
without this feedback, I personally have no idea how fast to run it in since it will cut just as easily
its more for myself, prolonging tool life even if it may not be that necessary to worry about.
-------------
I know the second I stop pushing the reamer in, most all pressure goes away as the reamer makes it final cuts