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robertb
01-25-2008, 10:42 PM
Can someone tell me if spiral lock threads are superior to typical V threads when fitting a new barrel to an action? With that said, how many 'smiths choose to use spiral lock over conventional threads?

Lastly, say I purchase a new custom action with threads in the tenon? If I want spiral lock threads on the barrel, will threads need to be recut in the tenon of said custom action? The action would be a Borden.

Gene Beggs
01-25-2008, 11:16 PM
Can someone tell me if spiral lock threads are superior to typical V threads when fitting a new barrel to an action? With that said, how many 'smiths choose to use spiral lock over conventional threads?

Lastly, say I purchase a new custom action with threads in the tenon? If I want spiral lock threads on the barrel, will threads need to be recut in the tenon of said custom action? The action would be a Borden.

Robert, after studying the chapter on barrel/receiver joint threads in Vaughn's book, I installed several barrels using the Spiral-Lock thread, but was never convinced that it offered any real advantage over the standard V thread. I went back to the standard thread and plan to stay with it.

No changes are made on the receiver threads when using the Spiral-Lock thread; only the barrel tennon.

If I were you, I would ask Jim Borden before using the Spiral-Lock thread in one of his actions.

Just my opinion, FWIW,

Later,

Gene Beggs

Bill Leeper
01-26-2008, 12:57 AM
The Spiraloc thread is a self locking thread which, like any other, depends on deformation of the thread to lock. It is hoped this deformation takes place on the barrel and not in the receiver. It is also hoped it doesn't cause the threads to gall. A good fitting V thread is likely just as stable. Regards, Bill.

alinwa
01-26-2008, 01:17 AM
robertb,


I'm with Gene, I'd call Jim :)


BUT.........Now that I've got a lathe I'm going to try another method (Which Harold also mentions) in an attempt to promote a more balanced lockup. What Vaughn was actually trying to accomplish with his Spiral-lock experiments was a more CONSISTENT TRANSFER of threaded joint load. Vaughn showed how the first thread in a conventionally threaded joint takes 35% of the preload, the second 23%, the third 15% and so forth until the rearmost threads are barely loaded at all. In an attempt to make all of the threads take load I propose to play with tapering the threads in a Rem style action. (I wouldn't TOUCH the threads in a Borden, :) ....yet :D ) I THINK that if one were to cut the receiver threads with about .002 (this is a WAG at best) of taper such that the thread diameter at the face of the receiver was slightly larger than at the rear then the rear threads would grab first and begin to load sooner than the front ones. MAYBE this would promote better loading, or MAYBE I'm just asking for a permanently galled together action.......this explains why I'm gonna' try it on a Remington ;)


It works to seal plumbing pipe threads...........:rolleyes:


justanotherthought



al

4Mesh
01-26-2008, 01:26 AM
Can someone tell me if spiral lock threads are superior to typical V threads when fitting a new barrel to an action? With that said, how many 'smiths choose to use spiral lock over conventional threads?

To claim superiority of application would mean that first you'd have to define some things about the use. Is your intent to shoot one group, or, to shoot many and have a long term competive rifle?

If you intend to solve a problem, you first need to know what the problem is. They're a bit tough to solve without knowing that. What exactly is the "problem". The thread you speak of is definitely stronger, but, did you ever see a barrel with a stripped thread? Does this thread offer more total surface engagement? Is that even something we're looking for?

All good questions.

I think it is anyones guess how many "smiths" use these threads. I would say that number is very very few. In my early attempts at gun building, I tried a few different methods of threading. About all I could say for sure was that I could spend a lot more time on the threading with no visible gain. I had no problem to solve so, solving it was tough.



Lastly, say I purchase a new custom action with threads in the tenon? If I want spiral lock threads on the barrel, will threads need to be recut in the tenon of said custom action? The action would be a Borden.

For the sake of proper terms, a receiver does not have a tenon. That's on the barrel. The receiver has a receiver ring, threads, etc. A tenon is a part that protrudes.

As a rule with this thread, only one part gets the thread with the additional material in the root. That thread more or less lives forever. The other part, has a standard V thread and that thread yields upon compression. So, that part after being installed one time will no longer be the same. The tops of some of those threads will be smashed over by design (those closest to the barrel face).

Harold in his book clearly had a problem to address and with this thread, he addressed it. He was using a wimpy action that was like, clinging to the barrel with it's fingernails. He had already cut the thing till all that was left was a potato chip. It stands to reason, anything at that point could be shown to help.

I use standard V threads on all my guns but I'm also not working with a Remington 721 like Ole Harold was. I don't think in the case of todays custom actions, that this thread could be shown to be of any advantage. jmo. I would guess that if someone on this board actually has found them to offer an advantage, they won't tell you here. Furthermore, even determining if they did offer an advantage would be a difficult job. With as well as the guns built for benchrest already shoot, showing the miniscule improvement shown by the Sprialock thread would be tough.

Also don't forget, Harold in his book was dealing with a tenon that was only .680 long. Most of the guys here are working with actions that have a thread length of 1" or greater. These are completely different animals from a Remmy. They also have about double the material around that tenon and that extra beef makes up for a lot of thread technology.

Remember, the premise of this thread is to spread out the contact area. It does not say anything about having MORE contact area. Just that less load is on each thread. If your action has an issue with the strength of it's threads, this thread will almost definitely help. The gun still goes bang, and there's still the same forces on the barrel/receiver when you pull the trigger. Harold showed in his book that there was a significant increase in the force required to remove the barrel after firing when using that thread. My guns don't have that problem. They're just the same torque after 2 years as they were day one (within my ability to estimate/measure).

Of the smiths I have ever talked to who bought the tools to do this thread (3), none of them say they do barrels that way.

alinwa
01-26-2008, 01:41 AM
4mesh,


Harold's work did change the way I look at the "long tenon" situation.........if only the first 6-8 threads are actually loaded then the length of the shank does essentially nothing, except add weight.


justathought



al

Gene Beggs
01-26-2008, 04:21 AM
4Mesh, that is an indepth and well written response. You can't get more thorough than that; well done.

Gene Beggs

Charles E
01-26-2008, 08:21 AM
As I understand it, the problem that Vaughn identified was that the barrel was not always "returning" to the same point in the receiver. His test was to mount a second scope on the barrel, and he discovered that occasionally, the barrel scope went to a different position than the receive scope after firing. The next shot printed at a different point on the target.

Since there was a joint between the barrel & receiver, he went after that joint.

If this problem can be found in a benchrest gun, the straignforward solution is to mount the scope on the barrel. That way, the barrel and scope are always pointed in the same direction. This can be done by using a barrel block, making a base that cantilevers back over the action, and putting the scope base on the block. The penalty is weight. I've done this on a HV, shoots fine. It does seem to have fewer mystery shots. But there is no proof the scope mounting is the reason.

As 4Mesh says, you first have to determine if there is a problem.

robdaniel
01-26-2008, 09:36 AM
Vaughn talked about using a collar to lock the barrel to the receiver. This would allow you to clock the barrel to see if it liked a different position. Has anyone tried it?

chino69
01-26-2008, 09:52 AM
robertb,
It works to seal plumbing pipe threads...........:rolleyes:


justanotherthought



al

Hi Al.
I read Vaughn's piece on Spiralock and looked into the design a little. The shadowgraph, which showed the loading of the threads, was very impressive. As in all things mechanical, there are specific designs for specific applications. If memory serves me well the Spiralock design is superior in highly cyclical or vibration rich environments, as in aircraft applications. While superior in one type of application, it may yield no additional added benefits over traditional threads. Vaughn's concept was valid but is the cost/benefit ratio worth the extra expense for rifle accuracy?
Chino69

Boyd Allen
01-26-2008, 10:09 AM
I believe that Greg Tannel of Gretan Rifles uses the Spiralock thread, and has for some time. You might give him a call.

alinwa
01-26-2008, 12:40 PM
Chino69,


My post wasn't referring to Spiral-Lock but to tapered.


al

jackie schmidt
01-26-2008, 07:05 PM
As far as I am concerned, the use of such gimics as spirolock threads on the tenon of a Benchrest Rifle is a total waste of time..........jackie

Gene Beggs
01-26-2008, 07:11 PM
Vaughn talked about using a collar to lock the barrel to the receiver. This would allow you to clock the barrel to see if it liked a different position. Has anyone tried it?

Rob,
I have been wracking my brain for years trying to come up with a good way of doing this. I have even hinted around on this forum to the various action makers to go to work on the design, but if any took the hint, they are keeping it to themselves. It may be that the design shown on page 119 of "Rifle Accuracy Facts" by Vaughn is the way to go. I'm thinking that the answer lies in something like the Savage barrel nut.

Vaughn's design is pretty close, but the thing that has always bothered me about it is that tiny little threaded ring at the front of the receiver that holds the barrel in place. How would you get a good grip on that thing to tighten it? I know, I know,,on page 120 it shows the ring has holes drilled in it for a spanner, but I still don't like it. I suppose you could make the forward part of it longer so you could place it in the barrel vise; that might work. I have never built one like this, but plan to experiment with it in the future.

During the past few years, I have dreamed up what I believe would be the perfect benchrest action.

A receiver made of aluminum with the scope mount dovetail integral with the action. This eliminates any concern for alignment or security of the bases. The Kelbly Panda is perfect in this regard, but I wish it was available with a hard anodize finish like the Stiller actions. I love my Viper and Cobra drop ports, I love the hard anodize finish and the coating on the bolt body and handle that makes them soooo smoooth! And the drop port feature is simply unbeatable! Since Stiller has a patent on the drop port, I guess my dream action will have to be built in his shops.

The Viper and Cobras that I'm presently shooting are my all time favorites, although if I could have it ALL, I would wish for the following:

1. A 30 degree coned breech. I know, I know,, you can't have that and use that great Remington extractor, but I'm just dreaming. By the way, if you have any concern about the reliability of that Remington snap-in extractor, forget it, that thing is bullet and fool proof!

2. A barrel/receiver joint that permits easy indexing of the barrel as discussed in the first part of this post.

3. Firing pin travel of .250.

That's it! I know I'm dreaming but, what the heck; I can dream; can't I? :D

Gene Beggs

4Mesh
01-26-2008, 07:38 PM
Al,

Concerning the longer tenons, If you think through what happens as Harolds thread load scenario plays out, that if the tenon has stretched enough that it unloads thread 4/5/6, it will also have stretched enough to reverse load threads 8/9/10 (or you get the idea). Provided of course the thread is not made with a mile of slop on the pitch diameters. I think in the case of most gunsmiths, they make barrel threads pretty much on the high side of the tolerance for a class 3 thread. I know mine leave very little room, but they're not overly close as to cause assembly issues either.

Tapered threads... Didn't Harold mention in his book something about a serious design issue with the tapered threads? Perhaps I'm remembering wrong. I was under the impression that he said there was some major mis-application problem with them but again, I may be mistaken. I don't even remember where that book is anymore.

Oh, and Al, Where Harolds design worked well you have to consider the differences between his rifles and a benchrest rifle.

First, he was using a remington with a 24" sporter weight barrel and factory stock. His amount of weight hanging on those short threads was considerably different than someone here with an 1.250 or 1.450 barrel hanging 30" out from the receiver (completely unsupported) and firing up to 20 shots at at time (getting scored on the last 5 or 10). Big difference.

Second, don't forget that every time Harold wanted to see if a problem was related to his gun or to his ammo, he went and grabbed a rail gun and shot the ammo in that. It's not like he didn't have a solid reference point to work with. Well, that rail gun didn't have spriralock threads in it! hehe. It was just a BR gun that shot because of it being a vastly different design. It was designed to be accurate, unlike the one he was working with that was designed to do not much more than go bang.

Jackie, that's about as outspoken as I've seen you here! Good Job! Lol

Gene, your dream action is waiting for you at the local steel supplier. Go buy a 1-3/4 hunk of 17-4 and a 1-1/4 bar of 4340 and get whittl'n. I also had an idea for a "dream action", cept, I just wasn't willing to wait for someone else to make it. (ps. it has v threads in it)

robertb
01-26-2008, 08:36 PM
Thanks for all of the information/advice...I apologize I had my nomenclature wrong (tenon, receiver ring, etc.) It looks like you guys translated what I was asking.

warthog
01-26-2008, 09:16 PM
At over $200.00 a insert, that cut external threads,that the chief application engineer would not sign off on, could be a problem if something went wrong. Do to the 30 deg. root loaded side of thread shank major dia. is smaller. This application Pat. was intended for internal threads only. Not here to rock the boat,just want to row it a little. Like a good friend of mind said. (I think I can smell the fumes) please don't call the teacher.

warthog
01-27-2008, 01:30 AM
there are actions on the market that have taper narrow in rear,just start checking, maybe you might own one.

msalm
01-28-2008, 08:51 AM
I've thought about that issue after reading Harold's book and my understanding was there wasn't enough centering torque to securely lock the barrel in a fixed position, meaning it was able to cant a bit. With today's methods of trueing actions and ensuring everthing was square certainly would seem to correct that problem. BUT I've considered adding a 45 degree chamfer to the face of the action and a like angle at the tenon shoulder the barrel would center in and seat. I think there was mention of the same thing in the Houston Wharehouse article. Someday I'd like to machine my own action and if or when I do, I'd make two 45 degree chamfers, one at the action face, and one down at the end of the threads. Two 45 degree shoulders with threads in between seems like a rock solid lock-up to me. The shoulder at the barrel tenon/shank would also have a 90 deg surface. It would be a little tricky to get the dimensions machined properly for solid contact on all surfaces, but in my mind it would be a very solid arrangement.

This obviously wouldn't work with a sandwiched recoil lug arrangement though.

This is just 2 cents from my theoretical side vs. actual experience though.

chino69
01-28-2008, 09:48 AM
Chino69,


My post wasn't referring to Spiral-Lock but to tapered.


al


Yes, I know Al. Pipe threads are tapered to seal and serve a different function than a component that will be threaded and unthreaded. When making up pipe threaded connections, the male end requires eleven threads with seven of those being full engagement threads. I don't know if those seven are loaded equally but they do form a wedging action when tightened. This magic number seven comes into play in calculating piping offset and pipe fitting. Pipe connections are not meant to be taken apart once made up as there is a degree of deformation involved; again the purpose is a leak tight connection. I'm not aware of a tapered threaded connection other than pipe and would be curious if one exists or any experimentation one has performed.
Chino69

Bill Leeper
01-30-2008, 11:02 PM
I can remember making up quick connect sleeves with a tapered ACME thread. The purpose of the taper was simply to provide clearance when disassembling. As soon as the collar was loosened at all, everything was clear. The taper also meant that, when assembling, the pieces were almost together before any turning was necessary; yet there was four inches of connecting thread once tightened up. A special connection for special circumstances. Quick connect and disconnect and tolerant of a dirty environment. I think a similar connection might be used on some drill stems. Regards Bill.

alinwa
01-30-2008, 11:05 PM
Just to clarify.........my idea includes ONLY a slight bell in the action threads, the threads on the barrel shank are to be parallel.


wathog, I'm gonna' check some a' mine, I use perty smart gunsmith's ;)


al

4Mesh
01-31-2008, 11:02 AM
Al,
I was aware of what you meant. Conversely, you could do it to the barrel instead and have the same effect without changing the action.

As Warthog said, there are acions on the market now that do this but I do believe they do it for assembly reasons. Actually, years ago, I measured a new action and found that in the thread so I inquired with the manufacturer about it. I actually was asking so that if they were not aware of their lathe needing trammed in, they could resolve it. I was told it was there by intent at which point I went on my way. I don't think you'll see any difference in this but it certainly won't hurt unless you go overboard and it does not sound like you intend to.

Stonewall
02-02-2008, 12:09 AM
"I think a similar connection might be used on some drill stems. "

Yes- Good point Bill.

Glenn:D

h-bar
02-02-2008, 09:24 AM
Phil you forgot the part where you have already made actions!!!! If people new of your experience doing so they would take you even more seriously!!!
Some of us know you personally and don't doubt much of what you say!!!
BTW I hope the Bower clan is having a good winter!!! See ya in the spring. My daughter Erin says hello!!! You shouldn't have been nice to her she will be like that burdock stuck to your leg!!!!

alinwa
02-02-2008, 02:18 PM
h-bar,


It's 4mesh..... ;) .......I know it hurts but this board is read all over the world and 4mesh made the posts to which you're referring. There is no Phil on this board.


al





4mesh,


I thought of that first ..... obviously it seems to be taking a much LARGER step to bell the action.......................until you think it through. Not least of which is, when it's done and if it works one can thereafter chamber/thread in one setup.



Well, that is, IF one is inclined to do it thru the headstock ;)




LOL


al

4Mesh
02-02-2008, 07:30 PM
HBar,

Tell Erin I said Hi as well. Tell her she's welcome to measure targets all day while I sit with a coffee and my feet propped up on the desk! Something tells me though she'll be the one with her feet propped up. I hope all is well in NY also. See ya in a few months.

Al,

You have no idea how right you are that there's no Phil here! It's a good thing too! :D

The more I think about this, this will be quite an interesting project to attempt on a Remington... Hmmm... I'm assuming you intend to use an engine lathe... most interesting... Thanks but no thanks! Sounds like a difficult prospect at best. Chasing .001, .0005/side in a cnc does not sound like a real hoot either. Better you'dn me. Might take less time to make a new receiver.

Anyways? What's this sissy-girl stuff about using a cheap action to try it? Ask anybody how afraid I am of trying stuff on a real action. May as well improve something you can be proud of when you're done!

If you screw it up, the worst case scenario is that your 1-1/8 16 Bat is now a 1-5/32 16! :cool: Haint no reason to be skeart. /edit/please chk sp on skeart! I think it's right!

dennisinaz
02-02-2008, 08:22 PM
Not to throw a wet blanket on this party, but after reading Vaughn's book, I have to take some of what he wrote with a large dose of salt and I am just one of many who feel this same way. His experience and specialty did not originate nor end with small arms. He was a rocket guy. Some principles are the same and can obviously be extrapolated but other really can't. He used some inferior stuff to arrive at many of his conclusions with no realistic sampling.

He has a very fertile mind but I feel he took some liberties with some of his theories.

I have a rifle barreled by Greg Tannel and it supposedly has the aforementioned threads. It IS a Remington and I have no idea if it helped. I suppose a guy could barrel enough of each to come up with a realistic answer to this question. Vaughn did not- maybe Tannel did?

I suspect there are far more near-perfect rifles out there without than with spiralok threads-

4Mesh
02-02-2008, 09:43 PM
Dennis,

The nice thing about Vaughn's book was that he didn't just say bla-bla-bla here's the answer. He said here's what I did and how, and this is what I found, if you want to try this, this is how to try it. That way if you wanted to make the experiment more accurate you could also do that. I don't think his area of expertise really matters. It's not like he was some idiot who couldn't be educated about two things in one lifetime. He also had some rather bright people to use for references (I think his son was one of em).

His sampling was enough to give a guy something to look for. Something to compare your own results to. If your result is the same as his, it's reasonably safe to say that on that test, his answer is reliable. If you test what he did and find a different answer, then I guess it's time to look farther, or decide who is wrong and why. Either way, you learn something new and the book was worth the retail cover price.

It's nice that you have the luxury of knowing even a little of the answer to this because you have a rifle with those threads to compare. These guys asking do not and they'd like to know first hand. Taking your word or mine for it is not going to teach them anything. For all I know, this thread might be the end-all-cure-all to accuracy. I didn't find that but that's not to say I didn't do something else wrong. With so many pieces to the puzzle, who knows.

warthog
02-02-2008, 10:18 PM
some actions have as much as .002 taper inside front to back,I would like to think that someone's cnc equip. can hold .0003 th or less or we all might be in trouble,when I first saw actions that locked on front shoulder as well on taper cone end of barrel shank to tapper in action cone hand made at that time on 338/378/KT 34" plus barrels,then fine thread came around because of more thread contact??, used on 20mm shoulder held rifles.then self locking,then one day had a gun shooting two separate points of impact,bad scope?loose mounts?bad bedding?stress?loose nut between driver and trigger?... Used J/B joined action to barrel,as you know we use jb to glue in actions,and yes you can take it apart,some center fire rifles have no threads just clamping force from split then clamped to together by bolts,nothing can beat a good square shoulder,and a few good threads,not as many as one might think. Hope someone can laugh about this,because I don't have a clue.

alinwa
02-03-2008, 12:20 AM
Pumba!........back slowly away from the keyboard, put down the bottle... no PUT down the bottle, don't drop it!


Ohhh, you CAN't......


ooops



Ok OK.....now just lay down here........theere ya' go.......you'll feel MUCH better in the morning.....


:D:D




ANYways.........I always love these wankers who pick on Vaughn (and there's been a LOT of them :) ) And YES Dennis I'm referring directly to you. :) Cite? Experiment? TEST of ANY sort??? Nope, just "I have to take some of what he wrote with a large dose of salt and I am just one of many who feel this same way."



Not ONE of you scoffers offers an alternative test or even a CITE! It's just "my buddy's friend said Vaughn was dumb because he shot this one time and HE found out that......." yada yada



I remember when Keith was alive and these gun hacks would PRINT this kinda' stuff and Ol' Elmer would invite 'em up and proceed to SHOW them how it WAS!






And here's the last one.... "I suspect there are far more near-perfect rifles out there without than with spiralok threads-" .....

WHERE does this stuff COME FROM???

Why should ANYone care what you "suspect"?

And what's a "near-perfect rifle"?



BACK IT UP MAN!!! On THIS board you gotta' do better than speculate if'n you're gonna' badmouth giants :D



LOL



al

h-bar
02-03-2008, 07:14 AM
4mesh-Hey any time you see Erin with me and you think she can help you do something like measure targets have at her!!! She loves to learn new things and really had a blast measuring targets. I know she would probably like to pull targets when she is not shooting also. She is one enterprising youth sometimes. Typical woman she loves money!!!!

alinwa
02-04-2008, 03:28 AM
dennisinaz,


I over-reacted to your reference to Harold Vaughn, I'm sorry. It's just that I met Harold before he passed and he was far from a blowhard, he asked that everyone check out what he'd found. I reacted to you when I was in fact reacting to the many guys who insistently bash Vaughn, some of them without even taking the time to understand just how committed he was to finding facts.


In re-reading my post I find it to be just a little over-the-top even WITH the smileyfaces......... :) (Even for ME!! :eek: )


I apologize. I don't know you well enough to get all up in your face.


:o



al



AND warthog,


I hope you understand that my post was in jest, prompted by THIS ((( " Hope someone can laugh about this,because I don't have a clue. " ))) quote..............


LOL


al

Tony Z
02-04-2008, 09:08 AM
This thread has been a good read. As a machinist i can add just a little here. The nature of machining on either a CNC or on most workshop lathe means that a taper is part and parcel of machining an internal thread. Mainly due to flex of the cutting tool and limited number of finish cuts made. In our application of barrel fitting this is a good thing.
Warthog is right in saying that the Spiral Lock thread should be done to the internal reciever thread.
As for the question of tapered locking threads, there are literally hundreds of them, most coming from the oil drilling companies, most of which come from the US oil companies and are known as API threads. American Petroleum Industry. Tapers vary from 1 degree to 7 or more and are either square, acme, buttress or a flattened v form thread. Threads can be cut to be square to the rod axially or square to the taper itself and in almost all they have large clearance depth factored in to store debris. In almost all these thread forms there is a test piece for go and no go and is not a simple case like most gunsmiths use of a simple 60 or 55 degree v form thread. Most all of these threadforms require hundreds of foutpounds of lock up to mate together require special locking and lock breaking devices. For this reason, aswell as production costs, commercial companies do not use any of these for firearm assembly. They may have some advantage, but i think that would be hard to prove.
The Dryseal threads, or pipe threads as you call them, are a jointing thread where sealing is the primary objective and load bearing is not a requisite. These threads are used in the form of male taper to female parallel or male parallel to female taper. Taper to taper does not form a dryseal and could be used as a load bearing thread if needs be. But there are far better options.

Tony Z.