6br case protrusion from barrel face

[hoz53]

FWIW, a Remington has about .150" of unsupported case. Whatever style or brand of action, I prefer about .005" of bolt nose to barrel clearance. The Savage has leaves less unsupported case than most actions do.

That's good info. It's been my understanding .005 to .010 bolt nose to barrel clearance is the norm. That's why I was surprised at the .018 figure earlier in this thread for a Savage. I didn't know savage leaves less unsupported case then a remington. I gonna go look at them. Do you think holding the bolt nose to barrel clearance to .005 helps accuracy in any way? Just seems like many accuracy gunsmiths use that figure. Thanks Mike

 

[swd]

Do you think holding the bolt nose to barrel clearance to .005 helps accuracy in any way? Just seems like many accuracy gunsmiths use that figure. Thanks Mike

It does nothing for accuracy at all, just case web support. In fact if it gets too tight and you bind up some garbage between the bolt nose and the back of the barrel can hurt accuracy.

 

[hoz53]

It does nothing for accuracy at all, just case web support. In fact if it gets too tight and you bind up some garbage between the bolt nose and the back of the barrel can hurt accuracy.

That is what I thought and wanted to hear about. Thanks for the Info

 

[gunsandgunsmithing]

That's good info. It's been my understanding .005 to .010 bolt nose to barrel clearance is the norm. That's why I was surprised at the .018 figure earlier in this thread for a Savage. I didn't know savage leaves less unsupported case then a remington. I gonna go look at them. Do you think holding the bolt nose to barrel clearance to .005 helps accuracy in any way? Just seems like many accuracy gunsmiths use that figure. Thanks Mike

It doesn't help or hurt accuracy. I don't buy into the idea that debris getting in there is good reason to leave more case unsupported. I've shot hundreds of thousands of rounds and never had it happen...but it is theoretically possible I guess. I forget where, but I read years ago that the Remington 3 rings of steel design is designed to have .003-.005 clearance at all bolt nose to barrel surfaces. Many, if not most, gunsmiths use more than that and Remington seemingly just can't hold that tight of tolerances in production. I'm fairly certain the article or book I read that in was quoting Mike Walker, the designer of the 700 and the 3 rings of steel.
Either way, it works like that. I've personally seen a Remington fire a ppc diameter case cartridge, on a 308 bolt face, that had a Sako extractor in it, hold up and do exactly as the 3 rings were and are designed to work, with 123,000PSI. I know the approximate pressure because it had a pressure trace hooked to it when it happened.
The Sako extractor did not come out and the system worked as it was designed. The bolt nose swelled to fit the counterbore and had to be beat out...but it held. The case did blow out at the extractor and the primer pocket went from small rifle to an oversized large rifle size.--Mike

 

[hoz53]

It doesn't help or hurt accuracy. I don't buy into the idea that debris getting in there is good reason to leave more case unsupported. I've shot hundreds of thousands of rounds and never had it happen...but it is theoretically possible I guess. I forget where, but I read years ago that the Remington 3 rings of steel design is designed to have .003-.005 clearance at all bolt nose to barrel surfaces. Many, if not most, gunsmiths use more than that and Remington seemingly just can't hold that tight of tolerances in production. I'm fairly certain the article or book I read that in was quoting Mike Walker, the designer of the 700 and the 3 rings of steel.
Either way, it works like that. I've personally seen a Remington fire a ppc diameter case cartridge, on a 308 bolt face, that had a Sako extractor in it, hold up and do exactly as the 3 rings were and are designed to work, with 123,000PSI. I know the approximate pressure because it had a pressure trace hooked to it when it happened.
The Sako extractor did not come out and the system worked as it was designed. The bolt nose swelled to fit the counterbore and had to be beat out...but it held. The case did blow out at the extractor and the primer pocket went from small rifle to an oversized large rifle size.--Mike

That's Great info Mike--Thanks-- I like hearing what Mike Walker said about it and how much pressure a 700 will hold. I wonder what a savage would do at 123,000 psi.

 

[savagedasher]

That's Great info Mike--Thanks-- I like hearing what Mike Walker said about it and how much pressure a 700 will hold. I wonder what a savage would do at 123,000 psi.

I don't know the pressure but we had one blow up when a guy left guy left a ram rod in a 338 blew the barrel off the action but the bolt stayed . Larry

 

[hoz53]

I don't know the pressure but we had one blow up when a guy left guy left a ram rod in a 338 blew the barrel off the action but the bolt stayed . Larry

I've heard of that happening to. That must be way lotta pressure.

 

[savagedasher]

Fast way to dissemble a gun It could of been the heavy brass rod . For that reason alone I would never use a brass rod it cleaned the scope off We have part that went through the roof .
Pretty much tell me never use a brass rod in a savage barrel Larry

 

[hoz53]

A

Fast way to dissemble a gun It could of been the heavy brass rod . For that reason alone I would never use a brass rod it cleaned the scope off We have part that went through the roof .
Pretty much tell me never use a brass rod in a savage barrel Larry

A little job security for the roofer. I'm sure a Dewey in there would have similar effect

 

[gunsandgunsmithing]

Ironically, I found the case..that had been lost for a few years under a shelf, that I am referring to in my previous post. It tells a little different story than I had remembered. It blew out on the EJECTOR side, not the SAKO EXTRACTOR side. Granted, with enough pressure, any piece of steel becomes shrapnel..but at the pressure indicated by the Pressure Trace, the Sako extractor was captive and seemingly, gave more case support than the ejector hole. Go figure!

I'll try to post a pic or two tomorrow. It's enlightening!

I had some brass hit me in the face but nothing bad, since I had on glasses. I do remember the distinct sound and feel of shrapnel hitting my glasses!

Short version of how this happened is that the phone rang wile I was working up loads for a wildcat that likes very fast rifle powder and/or slow pistol powder. You can figure out the rest. It goes to show, we must pay attention to what we're doing or it can cost us our eyesight or worse. I was not a rookie handloader...just one that got too careless. "I was SURE I was dumping the right powder!"...I was wrong!!

 

[hoz53]

Ironically, I found the case..that had been lost for a few years under a shelf, that I am referring to in my previous post. It tells a little different story than I had remembered. It blew out on the EJECTOR side, not the SAKO EXTRACTOR side. Granted, with enough pressure, any piece of steel becomes shrapnel..but at the pressure indicated by the Pressure Trace, the Sako extractor was captive and seemingly, gave more case support than the ejector hole. Go figure!

I'll try to post a pic or two tomorrow. It's enlightening!

I had some brass hit me in the face but nothing bad, since I had on glasses. I do remember the distinct sound and feel of shrapnel hitting my glasses!

Short version of how this happened is that the phone rang wile I was working up loads for a wildcat that likes very fast rifle powder and/or slow pistol powder. You can figure out the rest. It goes to show, we must pay attention to what we're doing or it can cost us our eyesight or worse. I was not a rookie handloader...just one that got too careless. "I was SURE I was dumping the right powder!"...I was wrong!!

Very interesting. I made one mistake like that when I started out. Fortunately it just resulted in some gas release and I had to beat open the bolt. Case head and primer pocket very expanded. That was 40 years ago and I think about it every time I load. Thanks for the info always good to learn more about this stuff

 

[Eddie Harren]

Fast way to dissemble a gun It could of been the heavy brass rod . For that reason alone I would never use a brass rod it cleaned the scope off We have part that went through the roof .
Pretty much tell me never use a brass rod in a savage barrel Larry

Professor Irwin Cory Lives! Master of "Double Speak"

 

[gunsandgunsmithing]

Here are the pics