SSG True Bore Alignment System

Unless that receiver is PERFECTLY round, both a collet and/or a 6 jaw chuck will impart stress. In fact, anytime you clamp anything in any type of fixture, stress is induced.

This is a beautiful device. Fantastic machining. It serves a real good purpose.

I watch gunsmiths take hours to true up with a four jaw. Adding stress like you can't belive to a hollow action. Then take all kinds of measurements when the machining is finished but the action is still in the chuck. Then remove the action and proclaim "perfect". What about the relaxed stress after the chuck is opened?

I use a six jaw, tru-adjust. The single best tool I ever bought for my lathe. Using Belvue (sp?) washers under the heads of the bolts that attach the chuck to the backplate, I loosen, tap the whole chuck with the receiver or barrel in the jaws, with a small lead hammer moving it ever so slightly to get the indicator to run true. Takes all of 2 minutes and I'm not stressing the receiver or barrel by tightening and loosening a four jaw.

But then again, what the hell do I know.............I'm just a garage gunsmith!

But I REALLY like this device and if it was for sale, might just purchae one...............
 
308nate said:
Greg,
to answer your question....I have run this system up to 2000RPM on my Haas but recommend RPM's be kept under 1000 RPM. In my CNC lathe I find the RPM desired (not exceeding 1000RPM)that produces minimal indicator movement then add a G50 RPM lock (and specify speed) so that when running constant surface feet per minute I do not exceed my desired RPM. As far as machine vibration, on the farthest out barrel and receiver that I have run into since using this system, I still have not felt even a pulse while placing my finger lightly on the bed ways or head, my lightest machine is around 3000lbs so again one must use common sense when using anything. If one needs to slow things down, by all means slow things down. but to date 1000 RPM has not been too fast for all that I have done with this.

All the best,
308Nate
Click to expand...

Thanks for the information 308Nate. I wasn’t concerned about barrel whip as much as a massive chuck being out of balance (depending on how it is adjusted and oriented on your gimbal plate). It might be a problem in my Mazak at 3300 RPM, but it sure looks like a nice setup otherwise…much better than some of the Mickey Mouse jigs and spiders that I’ve seen.

Greg Walley
Kelbly's Inc.
 
Thanks for stopping by Nate....... I've got no questions :) , balance-shmalance, we all run eccentric stuff every day. If it's too bad, balance it, no biggie.

you've come up with a wonderful product that will obviously stand on it's own merits, I give you KUDO's!!!!

I'm only peeved I never thunkofit

al
 
hi all
hat's of to nate for thinking out of the square.

great work:D
 
so francis......
when you build your next 30" plus bbl with your new tool, and run it up to 400 plus rpm to use carbide tools....tell me then how well the unsupported muzzle end does......
your funny too.( go look at the context of the original comment)

mike in co
 
First off Thanks guys for all the interest and support in the True Bore Alignment System! I thought that I would add just a few comments to clear up a few possible misconceptions/misunderstandings.

First. Some thoughts about the balance issue. The chuck and the cast back plate will be no further off center than any adjust tru or set tru chucking system. The center steel plate is the only plate that could possibly show more run out than the part you are chucking is out. The easiest way to think about it is the barrel or action is clamped in the chuck, therefore the chuck and the barrel are one as well as the backplate that the chuck is bolted to. The steel plate with the socket machined in it will be pushed off center to compensate for the angular misalignment. If this is not understandable I would be glad to expound on it more....Just food for thought.

If the bore of a barrel is far enough out to cause lathe vibration one would do well to turn the barrel shank between centers before chambering, threading and crowning.

Second, supporting the stock or barrel through the spindle. No matter what you are working on a machinist must support long barrels or cylindrical shafts when extending through the spindle. The True Bore Alignment System does not do this for you. treebasher made a comment earlier about someone being able to hold a short barrel in this system without supporting the barrel through the spindle, he is correct in that concept. then somebody else made an assumption that you would do the same with a long barrel...this is incorrect... the longer the barrel the greater the need to support to prevent a wreck.

A few comments:
Although one can machine accurately and precisely on a short barrel without supporting it through the spindle I still have the desire to run through bore flush. therefore I have devised a system on my Haas to do this as well as have a different system I use on my Bridgeport .

The reason for using the True Bore system with barrels is not to eliminate the need for support, but to eliminate the need to push on the barrel with the spider to bring two points of the bore into center.

Also the definition of when the barrel is too long and needs support will have to be determined by the machinest as I described in my earlier post.

Thanks again guys for your support,
Nathan
 
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Great ideas

Nathan nice work and idea!
For those that don't know Nathan D. He is a very talented and yet humble and modest person from the hours of phone conversations that we have had over the last 7 years. I've owned 2 of his rifles and 2 barreled actions and yes they shot lights out. His even bailed me out 3 weeks prior to a out of state hunting trip.

Nathan has some great ideas, check out his website
StraightShotGunsmithing.com

-Tim B
 
.308 Nate,

Well done.

This is one of those gadgets that has me slapping my forehead in a demonstration of why no hair grows on the front of my scalp because I can't figure out why I didn't think of it. The reason is probably because I'd have no way to make one truth be told. I think it is a much better way to hold a receiver for truing than the 8 bolt sleeve I use. That said, my 8 bolt sleeve was almost free since I made it myself and I don't do many receivers (3 total to date) because I just do them for myself, so free was the right price.

The only problem I see with this system is for the folks that like to align the muzzle and breech as opposed to aligning the bore in the vicinity of the chamber and letting the muzzle orbit. The system, used as demonstrated, essentially aligns the bore conceptually the same way Gordy does and lets the muzzle orbit. The outboard spider bolts are just set to prevent whip. They have no role in the alignment process.

I happen to think that's just fine, and in theory exactly the right way to do it, but those who ardently support centering the throat as one point and the muzzle as the other point (most on here unless I'm mis-remembering) should have "issues" with it since that will be very difficult to do with this tool.

Fitch
 
Hey guys,
Had to take a few pix of the progress.........hope you enjoy shiny metal.
Will be posting some more videos and pix of other cool stuff soon!


308nate


1-1/2" plate water-jetted circles.


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operation side one.

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operation two and three.

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plate two operation one.

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Hope to be finishing these up by end of this week to the middle of next......
 
That is one pretty picture!

Good for you.............Something about a "better mousetrap and they will be beating a path to your door!"
 
A few days back, I took 4 barrels out to SSG. While their Nate was so kind to let me spend the day and watch my components being aligned/dialed in the True-Bore Alignment System, and then machined.
The simplicity of the his system and stress free manor the system holds the work, makes so much sense to me, which leaves a lasting impression of perfection in my mind.

I have been privileged and blessed over the last 10 years or so to have several great gunsmiths do barrels for me, and have been honored to watch them perform their arts.
I've had barrels that were done in a "steady rest", some that were done through the spindle bore "rotationally", some that were done "adjusted outward with a spider", and now these that were done in the True-Bore Alignment System.

I have seen excellent accuracy come from all these setups of chamber/fitting and believe all their arts are to be commended!!!
I am not saying one way or the other will produce more raw accuracy, but am saying the TBASystem is the most practical and stress free setup I have seen to holding and dialing in a barrel.

To emphasize on what I saw while their, I will describe the process Nate used on the barrels. After dialing the barrel in to less then 1/2 of 10-thousands across the 4" of his SSG range rods, he then put a dial-indicator in the bore (near the proposed throat area) and again the indicator read less then 1/2 of 10-thousands. All adjustments were done to the TBASystem, none to the chuck, and the 30" barrels were "non-supported" at the outboard ends, through the spindle bore of his Haas CNC.
Next the CNC lathe cut the threads and tenon. In that operation I seen on the screen it was being done at around 950-RPM. Then the recess was cut, chamfers were made, and chamber boring was done, again at similar speeds (a little less then 1000-rpm).
After these operations were completed, he re-inserted the SSG range rod and the indicator repeated exactly less then 1/2 of 10-thousands across the 4" rod, and again put into the bore the indicator repeated spot on the same as from the start.
The chambers I have watched him ream, resulted the same as the fittings, with 100% repeatable indicator readings to all the areas of the chamber that he reached for with the indicator stand.
From start to finish, I seen no movement of the parts being held, as proven by the before & after indicator readings. A very lasting impression to say the least !!!

Donovan Moran
 
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Nice write up Donovan!

Does he use a reamer for the chamber or is he cutting the chamber with the CNC lathe?
 
Guys,
It's been awhile since I posted. It's been a crazy busy summer here.
I got a chance to take some video clips of my bolt holding fixture as well as a tapered bushing for holding barrels on a taper.
Thanks for all the purchases and interest. I am starting another run of these as I only have a few left.

 
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