Gene Beggs
Active member
This extreme rifle accuracy study has been much like a giant jigsaw puzzle. When I first got into benchrest twenty years ago, I thought I knew a thing or two about rifles and accuracy. 
I found out real quick, I knew very little.
Something I have noticed during the past many years is that bits and pieces of information come along and at the time, you know there is something very significant about it but you don't know where that piece of the puzzle fits. So you file it away in your mind thinking, "Someday, I'll discover where this fits." Such was the case recently with reduced tenon diameters.
My first Sporter was built on a beautiful stainless steel action, the stock was state-of-the-art graphite painted dark navy blue. It was beautiful and shot like you would not believe. At the time, the Stolle Panda was the most popular action and many of my friends used them. I soon noticed that the Panda would accept much higher pressures without encountering stiff bolt lift and 'click-at-the-top' extraction. I assumed the reason was due to the difference between aluminum and stainless steel. Wrong!
Only during the past few days have I understood what the real reason was; tenon diameter! Yep, the stainless steel action had a one inch tenon, the Panda is 1.062. The larger the tenon relative to the chamber diameter, the more pressure the rifle can take without experiencing tight cases.
This should have been obvious, but it has taken me twenty years to understand and I probably would have never figured it out if not for Stu Harvey. Thanks Stu.
After spending several days in the tunnel testing the barrel indexing system, I have arrived at the following conclusions;
1. The system works! Every barrel I have tested shoots best in one specific position.
2. The differentially threaded bushing system works but it is rather inconvenient to use and one must be willing to shoot reduced loads because of the smaller tenon.
3. The actions of today were not designed to be used with barrel indexing systems. Further advancements will come only when we have actions designed specifically for this purpose.
Later,
Gene Beggs
I found out real quick, I knew very little. Something I have noticed during the past many years is that bits and pieces of information come along and at the time, you know there is something very significant about it but you don't know where that piece of the puzzle fits. So you file it away in your mind thinking, "Someday, I'll discover where this fits." Such was the case recently with reduced tenon diameters.
My first Sporter was built on a beautiful stainless steel action, the stock was state-of-the-art graphite painted dark navy blue. It was beautiful and shot like you would not believe. At the time, the Stolle Panda was the most popular action and many of my friends used them. I soon noticed that the Panda would accept much higher pressures without encountering stiff bolt lift and 'click-at-the-top' extraction. I assumed the reason was due to the difference between aluminum and stainless steel. Wrong!
Only during the past few days have I understood what the real reason was; tenon diameter!
Yep, the stainless steel action had a one inch tenon, the Panda is 1.062. The larger the tenon relative to the chamber diameter, the more pressure the rifle can take without experiencing tight cases.This should have been obvious, but it has taken me twenty years to understand and I probably would have never figured it out if not for Stu Harvey. Thanks Stu.
After spending several days in the tunnel testing the barrel indexing system, I have arrived at the following conclusions;
1. The system works! Every barrel I have tested shoots best in one specific position.
2. The differentially threaded bushing system works but it is rather inconvenient to use and one must be willing to shoot reduced loads because of the smaller tenon.
3. The actions of today were not designed to be used with barrel indexing systems. Further advancements will come only when we have actions designed specifically for this purpose.
Later,
Gene Beggs
