That is an interesting read, and timely as I will be at the gunsmith next week to check the torque of my barrel - action. I want to tighten it to help with sight regulation and had been wondering what the ramifications might be.

Von Gruff.

The ramifications will likely be a warped action.
I've tried some of his ideas and they make sense but this one is bullshit.

quote:

Originally posted by huntingcat:
The ramifications will likely be a warped action.
I've tried some of his ideas and they make sense but this one is bullshit.

I gently but quite firmly and emphatically disagree with you, and don't understand your reasoning. Can you explain further?
Regards, Joe

This has been discussed a lot and I've seen no solid evidence that there is much to it. I do believe that barrels fitted with two contact surfaces form a more rigid joint. I know, from experience, that an angled contact at the shoulder forms a more rigid and durable joint. I believe that lateral stability in a threaded joint is a good thing. However, I see plenty of evidence that seems to support the claim that the conventional vee threaded joint is adequate for the job. If it were not, BR rifles wouldn't shoot as well as they do.
The Spiraloc (sp?)thread is a a locking type thread which relies on deformation of the thread in one of the mating pieces to lock. While it may well provide increased lateral stability, that wasn't the intent. I don't see the point in producing a weird thread on a barrel so either it or the receiver thread can deform under load. Regards, Bill

That book frequently gets quoted as gospel, but it's proper title should have been "Rifle Accuracy Opinions." His logic is at times flawed.

A LOT of serious benchrest shooters all use a torque wrench to set torque when switching barrels. Makes sense to keep the pressure the same.

Rich
Buff Killer/Super Shoot Competitor

quote:

Originally posted by Marc_Stokeld:
That book frequently gets quoted as gospel, but it's proper title should have been "Rifle Accuracy Opinions." His logic is at times flawed.

I think that you'll find that, even if his logic is flawed (in your opinion anyway), his results bear out his conclusions quite handily. He gives actual experiment results and quantifies them specifically, using modern reliable instrumentation and a logical scientific approach to his group shooting.

It's hard to argue with actual experiment results, regardless of any perceived logic flaws in the argument. His results speak for themselves and, for the moment at least, his conclusions are apparently the best info on the subject.

Can you give us an example of his flawed logic?
Regards, Joe

quote:

Originally posted by J.D.Steele:
I think that you'll find that, even if his logic is flawed (in your opinion anyway), his results bear out his conclusions quite handily. He gives actual experiment results and quantifies them specifically, using modern reliable instrumentation and a logical scientific approach to his group shooting.

It's hard to argue with actual experiment results, regardless of any perceived logic flaws in the argument. His results speak for themselves and, for the moment at least, his conclusions are apparently the best info on the subject.

Can you give us an example of his flawed logic?
Regards, Joe

It has been 10 years since I read that book, just as I was winding down in engineering graduate school. I have no desire whatsoever to reread it. Even if I read it last night I would not tell you. If you are going to be an abrasive dickhead about it in the way you phrase your challenge to me then I have no desire to try to carry on an intelligent discussion with you about anything.

Did he do a better job than almost anyone at trying to scientifically get to the bottom of things? He sure did. Does this mean everything in the book can be accepted as gospel? Not by a long shot. In any peer reviewed texts there will be discussion and dissention, and Rifle Accuracy Opinions is not an exception to this rule. Vaughn did some things that are judgment calls and some of his techniques are not as I would have done them. Again, this is normal for nay test. The problem is that he has more knowledge than most of the readers and they accept everything he says as facts. Granted, I would say that most of his statements are “facts” in my opinion, but that does not mean everything eh says is good. I can remember reading his articles in Precision Shooting (more than 10 years ago) and some of those had things I felt were seriously flawed in them. Going on old memories here, but I always remember thinking the book was much better than some of his PS stuff (which also gets quoted as gospel).

This is all I am writing in this thread.

It is not a definitive book, entitled Introduction to Accuracy by Dr. John Doe that you bought for Accuracy 301 with problems at the end of the chapters like:

quote:

1) A Rem700 has 24" #1 taper Chrome Moly steel barrel with 1 in 10" twist and 200u" finished bore with a resonant frequency of 1000 Hz and a Q of 50 in .243 cartridge at 2800 +/- 75fps. The bullets weight 100 gr with the center of momentum .002" from geometric center. The rifle and scope weigh 8 pounds total with a compliance of .001"/pound compliance in the connection to the 2 pound stock. Wind gusts are 3 mph peak to peak. The cartridge neck is 1 degree crooked at the base. The chamber throat is .244". The rifle moment of inertia is 2" below the bore line. The shoulder compliance is .05"/pound +/- .025"/pound. The trigger force is 5 pounds and parallel to the bore line +/- 10 degrees.
A) Calculate the average group size for 5 shots.
B) Calculate the change in group size if the barrel threads are 5 degrees off bolt bore and large ring axis.
C) Calculate the number of groups needed to very with 90% certainty that that barrel thread effect exists.

It is not that kind of book.
That kind of book does not exist, because we do not have a rifle accuracy science, we have a rifle accuracy folklore with rituals. Just like the ancient Japanese could make some great laminated steel swords with ritual, we can make some great rifles.

What does it all mean?
"Rifle Accuracy Facts" is not THE path to accuracy, it is just some hints for what to choose from the rifle accuracy mythology rituals.

quote:

Originally posted by Marc_Stokeld:
If you are going to be an abrasive dickhead about it in the way you phrase your challenge to me then I have no desire to try to carry on an intelligent discussion with you about anything.

I believe you have (at least) 2 problems:

A) Apparently you don't have any conception of what a REAL abrasive dickhead is like, 'cause IMO my question was phrased calmly and courteously, unlike your response, and
B) Apparently you have no intelligent answer for my question about specific examples of his logic flaws, 'cause you choose to turn tail and run. Back in the dark ages when I was studying engineering up at the state cow-&-chicken school, we had a name for wannabes like you. I just retired from several decades in the commercial nuclear power business, I don't think you'd last very long there.

So, to return to the original subject, if Vaughn's logic is so flawed, how come his experiments resulted in improved accuracy?

Musta been one of those vast right-wing conspiracies....
Regards, Joe

I didn't read the article but us Savage shooters tend to torque barrels all the time. The current wisdom is that all it takes is about 35-40 lbs-ft to set the barrel.