Cone Bolt
- Thread starter Louis.J
- Start date
What he said.
On flat breach actions the tip of the bullet will occasionally contact the flat portion of the tenon and stop the bolt. Very disruptive to say the least. I have had a couple of actions prone to this and have gotten into the habit of taking a bit of extra time and sliding the cartridge on into the chamber instead of just sitting it on the loading ramp.
For a rifle with a magazine you would need to mess with the feed lips to eliminate this from happening in a fast reload situation.
On flat breach actions the tip of the bullet will occasionally contact the flat portion of the tenon and stop the bolt. Very disruptive to say the least. I have had a couple of actions prone to this and have gotten into the habit of taking a bit of extra time and sliding the cartridge on into the chamber instead of just sitting it on the loading ramp.
For a rifle with a magazine you would need to mess with the feed lips to eliminate this from happening in a fast reload situation.
Thank you Mike the reason I was asking was I thought it was to self center the bolt with the breach which brings me to my next question has anyone created a taper at the front of the action and a matching taper on the barrel so when the two are screwed together the barrel not only self centers it would also stay centered and locked in place per say kind of like a morse taper of which might be conducive to achieving extreme accuracy.
J.Louis
J.Louis
C
Cheechako
Guest
Louis - Yes indeed they have. In fact, it's my own personal opinion that the idea of the coned bolt face and breech originated with this sort of self-aligning in mind. But, it's only my opinion because I have no evidence to back it up and the originators of the idea are long dead.
But, the bolt and breech do not have to be coned. A well fitted straight bolt nose and barrel recess, such as found on some actions, such as the Rem 700, will do the same thing. And please, don't anyone say that the bolt touching the barrel causes inaccuracy, because I'm only going to ask you, "Says who??"
Ray
Boyd Allen
Active member
In my discussion with Bob Brackney, about how he fits Remington bolt noses in recesses. on an action that he has trued up and sleeved the bolt, he told me that he fits the nose quite close on the diameter, and given that he only sleeves the rear of the bolt, and depends on fit of the bolt nose in the barrel recess at the front, there can be no doubt that it touches...sideways (my conclusion)....BUT he allows enough clearance ( I seem to remember .007, but it has been a while.) lengthwise that it will not touch, because that will cause accuracy problems. So, as it turns out, like many things, it depends. I presume that my source is well enough qualified?
Boyd
Boyd
C
Cheechako
Guest
Boyd
Bob B is indeed well enough qualified when it comes to accurizing the Remington actions. In fact, it was Bob hisself who convinced me to adopt the fitted bolt nose into all of my Remingtons, something that I've been doing now for over 30 years. His standards back then were a nose diameter with less than .0005" clearance in the barrel counterbore, and length wise clearance of anly .001". As Bob was wont to say, that's close enough! A fitted bolt nose with a rear sleeve and you can't get any straighter than that. Of course, such precision changes to a Remington action are all but a forgotten art in today's world of custom actions made with computer operated machinery.
Ray
Bob B is indeed well enough qualified when it comes to accurizing the Remington actions. In fact, it was Bob hisself who convinced me to adopt the fitted bolt nose into all of my Remingtons, something that I've been doing now for over 30 years. His standards back then were a nose diameter with less than .0005" clearance in the barrel counterbore, and length wise clearance of anly .001". As Bob was wont to say, that's close enough! A fitted bolt nose with a rear sleeve and you can't get any straighter than that. Of course, such precision changes to a Remington action are all but a forgotten art in today's world of custom actions made with computer operated machinery.
Ray
Boyd Allen
Active member
Ray,
Since I don't claim to have a perfect memory, (not saying you do) I just got off the phone with Bob, He said that I was correct about the lengthwise clearance, but the reason that he gave was to make some room for any "trash" like a brush bristle. The way that he described the fit on the diameter was a "slip fit". I asked him about the clearance for a coned bolt, and he indicated that they shouldn't be too close for the same reason.
Boyd
Since I don't claim to have a perfect memory, (not saying you do) I just got off the phone with Bob, He said that I was correct about the lengthwise clearance, but the reason that he gave was to make some room for any "trash" like a brush bristle. The way that he described the fit on the diameter was a "slip fit". I asked him about the clearance for a coned bolt, and he indicated that they shouldn't be too close for the same reason.
Boyd
C
Cheechako
Guest
Bob must be getting soft in his golden years. Making allowances for trash was never his way.
There's an old military saying, "Arguing over minutia is strictly forbidden." I think that's where this thread has gone.
Ray
There's an old military saying, "Arguing over minutia is strictly forbidden." I think that's where this thread has gone.
Ray
Boyd Allen
Active member
YA think? Where's the fun in that? Seriously, I agree completely.
E
eww1350
Guest
I believe that the tapered (45 dergree) barrell shoulder fit was one of the topics in the "Houston Warehouse" article...find that article and it fully describes the method used..and the results...BUT no one uses it today.?
Eddie in Texas