can a barrel be tuned to adjust direction of spin drift?

[Plastikosmd]

I don't know about barrels but the luger artillery rear sight is canted for spin drift, or really the magnus effect. As u elevate, it compensates. Love the germans, incorporating that into a pistol!

Here is a quick read on ballistics mentioning it when talking about projectiles fired from aircraft

http://h-net.msu.edu/cgi-bin/logbro...3&week=a&msg=uh7AC8CVoSNHfxgNS+5O9g&user=&pw=

 

[murf]

you are being "thrown a curve ball" on the spin drift issue. don't know anything about xraying a barrel/action, but it also sounds hoaky.

murf

 

[Charles S]

there is a process called "clocking".......essentially, you mark a dot on your barrel and shoot a group......then you rotate the barrel 90* and shoot another group.....then another 90*.....and another 90*..

and what you will be left with is a 4-leaf clover leaf patter on your paper.....

the current theory is that if you clock your barrel so that your groups are at the 12:00 or 6:00 position, that you will get more consistant group out of your gun....

Very interesting. I cannot, in my mind, understand how this would affect wind drift. I am intrigued. Would you mind expanding. I am very interested. Again, I am about to build another long range rifle.

 

[Charles S]

The rifle is a 6.5cm. I would think I am amiss in my understanding prior to making absolute statements of fact regarding statements made as to manufacturing. This being said, I would ask the discussion be maintained to the thread and see no reason to include the manufacture. I ran several commercial enterprises where numerous customers believed that they new considerably more than I. I ask here that if you wish to pick on someone, please pick on me. I am humbled at the vast amount of information here and now ask for the same in your response. Thank you.

I can respect that.

I understand your concern, but if a manufacturer is making wild claims it should be made known to warn potential buyers. Kind of like the old time snake oil salesmen who claimed their "magic elixir" would cure anything. I wonder how many folks suffered, or even died, because they believed those claims.

Agreed!

In that light, although I am a long range shooter I am certainly not an expert on long range shooting and on external ballistics. I will allow others to expound on spin drift more.

They also x-ray the barrel and action and make adjustments to ensure action to barrel alignment.

Let me therefor expand on that statement. A precision rifle build is held to amazing tolerances. With some surfaces held to the 1,000s of an inch and many to 10,000. Standard X-ray resolution is in the 10s of an inch. I am not certain as to how that can help. If we step up to CT scan we can go to 0.25 cm slices which equates 100s of an inch and with certain software can be improved by a factor of 2. This could, potentially be helpful, however I am curious as to what manufacturer has access to that kind of technology. That technology is used in the aerospace and aviation industry and cost an enormous amount of money.

Which brings in to question the validity of that claim. Maybe I am mistaken. A true expert in NDT (non-destructive testing) could help out here.

 

[benEzra]

there is a process called "clocking".......essentially, you mark a dot on your barrel and shoot a group......then you rotate the barrel 90* and shoot another group.....then another 90*.....and another 90*..

and what you will be left with is a 4-leaf clover leaf patter on your paper.....

the current theory is that if you clock your barrel so that your groups are at the 12:00 or 6:00 position, that you will get more consistant group out of your gun....

I suspect that the spokesperson/gunsmith/whatever was thinking of clocking and got his terminology confused with spin drift, which is related to the bullet itself rather than the barrel.

As to X-ray, it is also possible that a non-technical employee was trying to describe some technical method of NDI or QA that they use and got his terminology confused as well. What the OP was told is obviously incorrect, but it may be that the company was not being malicious, just didn't have all their representatives up to speed on precisely what they do. I've experienced the fog of "technical trickle-down" myself in other contexts, when people without technical foundations try to explain technical concepts. So I wouldn't jump to the conclusion that it was malicious.

 

[Charles S]

As to X-ray, it is also possible that a non-technical employee was trying to describe some technical method of NDI or QA that they use and got his terminology confused as well. What the OP was told is obviously incorrect, but it may be that the company was not being malicious, just didn't have all their representatives up to speed on precisely what they do. I've experienced the fog of "technical trickle-down" myself in other contexts, when people without technical foundations try to explain technical concepts. So I wouldn't jump to the conclusion that it was malicious.

Agreed, It is hard to make any conclusion based upon the limited information. I hope my post did not come across as otherwise. I just question the validity to the X-ray claim as posted in the thread. However, I must admit my knowledge of precision gunsmithing is limited and there may be techniques of which I am not aware or someone may indeed have resources beyond what I would expect in a gun shop.

 

[Welding Rod]

Spin drift is predictable with long range shooting software. If it were possible to somehow effect change to spin drift by some compensation trick at the gun, software predictability would be lost. I don't see how that would be desireable.

 

[stoky]

I seem to recall accounts of M.L. McPherson cutting and crowning barrels at the range to find the sweet spot where the bullet was leaving the barrel at the 12:00 or 6:00 o'clock points in barrel gyration.

YMMV, don't try this at home kids

 

[CANNONMAN]

M1, I do believe in giving credit where credit is due. However, this request seems more like give us direction to the castle so we storm it and kill the monster. I may have gotten the concept wrong. The sales guy may have misunderstood. The guy who taught the sales staff my have spoken in error. Tech guys rarely speak with lay eloquence. And this thread has nothing to do with a manufacture.

243 winxb: I completely agree with you in that I wish you to never cross my path in responding to any of my current or pending threads. If your desire is to hurt me with your illiterate comments as you boast your phenome status I suggest you call NASA and tell them you are available.

To all of you who would like to see this thread continue: I know the designer, smith, and president of the company. I will take you thoughts and comments to them and ask for clarity. If your desire is to belittle me, be sure to show what you are writing to your wife, kids and parents. I'm sure they will be quite proud of you.

Last: Thank you all for your enlighten comments. I look forward to knowing how this will go. There was a time when we were all quite certain of how things worked and we killed those who would disagree. Now we know the earth is not the center of our universe.

 

[Sam1911]

Ok, so it looks like on further reflection, there was more confusion than understanding in the original discussion and a lot of folks got halfway out of joint simply due to what must be declared to be details "lost in translation." (Which pretty much ALL of the details were!)

Cannonman has revisited the conversation with his 'smith and has rebooted his inquiry here:

http://www.thehighroad.org/showthread.php?p=10253291