Can easily fit a .790" diameter barrel....

B

Bill Calfee

Gun Fool
Can easily fit a .790" diameter barrel....


CYA pistol fool friends:


With the .750" diameter barrel thread of the DiOrio V-3 XP action, I can easily fit a barrel as small in diameter as .790".


I've not discussed this with Anthony yet, but, I suspect that knowing some pistols will be using barrels of .800" diameter, that he''ll keep the radius at the barrel thread opening at a minimum....

Also, he'll keep the barrel thread opening in the action face as close to .750" as possible...



My 10-X based MD-PAS pistol uses a .770" diameter opening and I'm running a .800" diameter barrel....

So anyone can do the math.

___________________________________


CYA pistol fool friends, if you have my book you might go to the chapter titled "Potpourri 4".



In this chapter I run a spearment where I start removing the barrel threads on a barrel for my 52 D Winchester slave action.


I first shoot the barrel with all the original threads....

I then remove all the threads but three, and shoot it again...

I then remove all the threads but two, and re-test....


Now this is mind blowing.....


I then shoot the barrel with just a single barrel thread.....


There's pictures of the barrel and the various groups....


I may discuss this amazing spearment later.......


Cause it is mind blowing.........


But what this spearment actually does, is to demonstrate that for RFBR actions it doesn't take but a few thousandths of barrel shoulder to safely secure the barrel, while at the same time producing the absolute best accuracy possible.


Your pistol fool friend, Bill Calfee

___________________________________


PS:


Again, if you have my book, and haven't read it already, you might want to read the "Potpourri 4" chapter.



Man I'm chomping at the bit....


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A fascinating spearment

A fascinating spearment


CYA gun fool friends:


Last night I re-read my spearment in the "Potpourri 4" chapter of my book.


If you have my book it would be a most interesting read, since it parallels the subject of how much barrel shoulder does a RFBR action need to safely secure the barrel and produce best accuracy.


As an example:


The 52 Winchester uses a .750" x 20 pitch thread.......


With the clearance between the crown of the barrel thread and root of the action thread, each thread probably has not much more than .020" of actual bearing surface.


My last test was after I had machined all the threads from the tenon, except one single thread.


So the barrel was held to the action by a single thread with about .020" of bearing surface.


The test groups with that single thread, were equal to, or better, than with two, three or the full thread pattern.


So .020" of barrel shoulder is gobs plenty for a RFBR action......gobs plenty.



There's some more fascinating aspects about this series of tests....which I'll describe later...


Such as:


Did the extractor slots line up correctly after removing all but one of the threads?


The answer, yes.


Secondly, did I have to reduce the tightening torque when tightening the action to the single thread, to keep from stretching it, causing the extractor slots not to be aligned?


The answer is, no.


As a matter of fact, if any of you CYA folks could have tightened the action to the barrel with the full thread pattern, then tightened it with the single thread, none of you folks would be able to tell any difference in the pressure required.


The singe thread was just as solid as the entire thread pattern.


More later....


Your pistol fool friend, BC


_______________________________________________


PS:


This is why we'll be able to use barrels as small in diameter as .790" on the new DiOrio V-3 XP pistols...




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