Enlarging the counter bore on a 700 WITHOUT removing the barrel?
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rcmodel
Member in memoriam
Counter-Bore?
Care to expand on that?
Are you talking about the muzzle crown?
Or the rifling leade / free-bore?
Or something else?
rc
Care to expand on that?
Are you talking about the muzzle crown?
Or the rifling leade / free-bore?
Or something else?
rc
rcmodel,
Here's a drawing of the cross-section of a typical barrel showing the chamber and barrel threads. The counter bore (dimensioned in the drawing) accommodates the bolt nose when the bolt is closed. The outside dimension of Remington 700 bolts is approximately 0.695". The factory counter bore dimension is 0.700" i.e. about 0.005" of clearance. The Badger Ordnance M16 type extractor needs a counter bore dimension of 0.785" which is 0.085" larger in diameter.
Here's a drawing of the cross-section of a typical barrel showing the chamber and barrel threads. The counter bore (dimensioned in the drawing) accommodates the bolt nose when the bolt is closed. The outside dimension of Remington 700 bolts is approximately 0.695". The factory counter bore dimension is 0.700" i.e. about 0.005" of clearance. The Badger Ordnance M16 type extractor needs a counter bore dimension of 0.785" which is 0.085" larger in diameter.
rcmodel
Member in memoriam
AH HA!
But wouldn't that do away with the famous & much heralded Remington "Three rings of steel" surrounding the case?
That counter-bore is what keeps the bolt face flange from having an escape route in the event of a blown case. It is also what makes the 700 so dang strong.
Seems like just making a cut for the extractor clearance would be better then cutting the whole ring away all the way around the bolt face.
Anyway, the SAKO or M16 style extractor conversion often turns out to not work as well as the one Remington put in them.
Not to mention the part about making the very safe action much less safe.
rc
But wouldn't that do away with the famous & much heralded Remington "Three rings of steel" surrounding the case?
That counter-bore is what keeps the bolt face flange from having an escape route in the event of a blown case. It is also what makes the 700 so dang strong.
Seems like just making a cut for the extractor clearance would be better then cutting the whole ring away all the way around the bolt face.
Anyway, the SAKO or M16 style extractor conversion often turns out to not work as well as the one Remington put in them.
Not to mention the part about making the very safe action much less safe.
rc
Advisable? Increasing the gap or opening the counter bore may never be a problem, then the first round you fire could have an insipient case head separation, after that comes the excuses, first excuse "I assumed it was not important".
http://www.remington.com/library/press/2009/Firearms/2009-6.asp
F. Guffey
http://www.remington.com/library/press/2009/Firearms/2009-6.asp
F. Guffey
rcmodel said:
No ... there are still "three rings of steel" ... the bolt's nose, the barrel threads and the receiver. But let's be honest, that Remington slogan is more marketing hype than anything since it's the bolt face and locking lugs that take the brunt of the force. Can you show that the bolt nose expands in diameter by 0.005" and then exerts pressure on the walls of the counter bore? I'd bet my dog that the bolt nose doesn't expand by 0.005".
rcmodel said:
First off, there's a pressure relief hole in the receiver that would vent the counter bore. Also, if you look at the bolt face and nose of Remington 700 bolts in both magnum and standard calibers, you'll notice that the wall thickness of the nose is MUCH thicker on the STANDARD calibers vs. the magnum ones. This is a clear indication that the walls of the bolt nose ARE NOT subjected to a great deal of stress. If they were, the magnum calibers would need a larger diameter bolt. The case head isn't flowing outwards parallel to the bolt face ... the case head is being pushed directly back against the bolt face which is supported by the bolt lugs.
rcmodel said:
How would you do that?
rcmodel said:
I'd like to see one piece of scientific evidence that the action is "much less safe" with an M16 or Sako style extractor. Many manufactures of quality actions offer models based on the 700 with Sako or M16 style extractors. Many top gunsmiths offer those upgrades to current 700 actions but there's a lot of internet BS surrounding the extractor conversion on a 700 bolt. If they're so unreliable, how come a number of military and police units, not to mention competitive shooters, have that very conversion? The few bad reports that I've read have come from dubious sources and based on my research, probably weren't done correctly.
fguffey said:
Are you saying that increasing the counter bore by 0.085" would lead to "insipient case head separation" or are you saying that in the event of ICHS, the larger counter bore would be a problem?
The M16 style extractor is a done deal on my .308 since the action truing by Krieger has affected extractor performance and a new extractor won't resolve the issue. I'm not blaming Krieger for this .. they did what they were supposed to do.
Thanks.
I would say the clearance before the Bubba cut is .0025, increasing the gap would not have an effect on head space, the 'ring' is a JIC thing 'JUST IN CASE' the back of the case lets go for any reason, the small gap controls the hot high metal cutting gas escape, if you want to increase the gas flow, increase the gap, or purchase a rifle without the ring. I do not have a Remington rifle with the ring, all of my Remingtons are 03s and M1917s.
F. Guffey
F. Guffey
Owen
Moderator Emeritus
1858, there is a collection of blown cases on benchrest.com, that illustrate the issue with the SAKO/M16 extractor.
The agency I work for converted to the SAKO and then the M16 extractor on their .300 WMs. There was no real improvement in extraction or ejection. It's a fad.
The agency I work for converted to the SAKO and then the M16 extractor on their .300 WMs. There was no real improvement in extraction or ejection. It's a fad.
Owen
Moderator Emeritus
oh, to answer your question,
If you want to do a good job with the counterbore, yes to need to take the barrel off. The counterbore is the same diameter (ok, a little larger) than the bolt lugs.
I suppose you could make a bushing that slides down in the raceway to support a single point tool, but that is a heck of a lot more work than spinning the barrel off.
If you want to do a good job with the counterbore, yes to need to take the barrel off. The counterbore is the same diameter (ok, a little larger) than the bolt lugs.
I suppose you could make a bushing that slides down in the raceway to support a single point tool, but that is a heck of a lot more work than spinning the barrel off.
Last edited:
Howard Roark
Member
Use a Sako extractor and there is no need to cut the barrel.
A solution looking for a problem.
If I remember correctly Winchesters with the extractor inside the bolt don't have any protrusion into the barrel.
A solution looking for a problem.
If I remember correctly Winchesters with the extractor inside the bolt don't have any protrusion into the barrel.
rcmodel
Member in memoriam
No, actually it isn't.
During the development of the 721 - 722 action back in the 50's, over-pressure loads were shot in them that went above 100,000 PSI. Well above any other action then in existance. Those rifles later became the Model 700.
That is well above the point brass cases melt and begin to allow gas to escape the action and take it apart like a bomb.
The little gas escape hole in the receiver cannot begin to handle it all.
The minimum clearance between the bolt flange and barrel recess would be reduced to zero in the event of a case failure. The bolt flange would be blown out to expand tightly against the barrel recess.
So the flange becomes the gas seal after the case can no longer do it.
Anyway, I'm through with this.
I told you what it does in the first post, so if you want to go ahead and do away with it, gofer it.
rc
owen, thanks for being the only one to actually answer the question that I asked. My original question was somewhat vague for that very reason ... I was looking for a straight answer but knew that it would turn into an anecdotal, unscientific a$$ whooping. I find it interesting that folks like Badger Ordnance have done Finite Element Analysis (FEA) along with tens of thousands of rounds of testing to show that their M16 style extractor does in no way, shape or form reduce the safety or performance of the 700 action, and yet to the "experts" here, it's virtually sacrilegious to even suggest that the 700 extractor can be improved on in with a well-engineered system. Even more ridiculous is that the "experts" don't provide one shred of evidence, one calculation, one stress analysis etc. to support their position ... just their opinion along with the tired phrase "a solution looking for a problem".
I see that removing the barrel is the best solution and that as good as our machinist is, he doesn't need any extra challenges.
Thanks.
I see that removing the barrel is the best solution and that as good as our machinist is, he doesn't need any extra challenges.
Thanks.
Howard Roark
Member
1858, This question was better asked of your good machinist rather than an internet forum.
For future referance a boring bar should not be inserted more than a ratio of 4.5:1. Thats four and one half times it's diameter. The depth of the action clearly will not allow this.
I didn't see any extractor testing data on Badger Ordnance's website. I'll take real world TTF over FEA anytime. I stand by my tired phrase and I sincerely hope you enjoy your extractor.
For future referance a boring bar should not be inserted more than a ratio of 4.5:1. Thats four and one half times it's diameter. The depth of the action clearly will not allow this.
I didn't see any extractor testing data on Badger Ordnance's website. I'll take real world TTF over FEA anytime. I stand by my tired phrase and I sincerely hope you enjoy your extractor.
Howard Roark said:
Howard, that's excellent information for non-machinists like myself so thanks very much. I'll definitely be removing the barrel.
Their web site isn't exactly brimming with information but it's easy enough to call them up and talk to their engineers ... I've called them and spoken to them three times in the last ten days getting through to them first time on each occasion. They're very serious about what they do and I have a number of their products and am impressed by their quality.
Science of nomenclature, Remington/ring of steel, this is the reason RC thought it was a guessing game,
Can the counter bore be opened up (advisable) my fault, because you did not know what 'it was called, I assumed you did not know what 'it' was for.and you omitted the rational as to why, so I do not know if you are in the CYA mode or like most, you have perfect hindsight
I am not the engineer, but,If a chamber can be reamed while the barrel is installed in the action with a piloted reamer, how long would it take an engineer (or machinist) to figure the 'counter bore' could be cut or removed with a piloted reamer. or with the use of an expandable guide, the reamer and or guide would allow the work to be done by hand and held in a vise, and if someone made piloted end mills and if someone could drill a hole (pilot) through a go-gage, yes it can be done, no I do not believe it should be done and I know I could do it three different ways without removing the barrel, but I will not drill and tap a receiver without removing the barrel.
No, complete removal of the counter bore flange (ring of steel) would have no effect on head space, yes removing the counter bore flange (ring of steel) compromises the safety built into the design.
Again, I do not know how much play or slack there is between the receiver and bolt ,with out the barrel, the counter bore could part of the design to align and support the bolt.
For get the rifle, I want some of those cases Ackley used to test those rifles he could not blow up.
F. Guffey
Can the counter bore be opened up (advisable) my fault, because you did not know what 'it was called, I assumed you did not know what 'it' was for.and you omitted the rational as to why, so I do not know if you are in the CYA mode or like most, you have perfect hindsight
I am not the engineer, but,If a chamber can be reamed while the barrel is installed in the action with a piloted reamer, how long would it take an engineer (or machinist) to figure the 'counter bore' could be cut or removed with a piloted reamer. or with the use of an expandable guide, the reamer and or guide would allow the work to be done by hand and held in a vise, and if someone made piloted end mills and if someone could drill a hole (pilot) through a go-gage, yes it can be done, no I do not believe it should be done and I know I could do it three different ways without removing the barrel, but I will not drill and tap a receiver without removing the barrel.
No, complete removal of the counter bore flange (ring of steel) would have no effect on head space, yes removing the counter bore flange (ring of steel) compromises the safety built into the design.
Again, I do not know how much play or slack there is between the receiver and bolt ,with out the barrel, the counter bore could part of the design to align and support the bolt.
For get the rifle, I want some of those cases Ackley used to test those rifles he could not blow up.
F. Guffey
Almost seems like the question was asked to bait responses so the OP could sneer at the expected replies.
If I wanted to do that job, I would remove the barrel, but I agree that the Sako extractor is more of a fad than an improvement (like a lot of other "improvements" in the gun after-market industry).
Jim
If I wanted to do that job, I would remove the barrel, but I agree that the Sako extractor is more of a fad than an improvement (like a lot of other "improvements" in the gun after-market industry).
Jim
Jim Keenan said:
Not even close!!
owen, I checked out www.benchrest.com but haven't been able to find any blown cases caused by M16 or Sako extractors but I'm still looking.
rcmodel said:
Based on this Remington owner's experience with a blown case, I have to wonder about that. A number of competitive shooters are "upgrading" to cone-shaped bolt noses in their 700s, so I'm of the opinion (simply an opinion), that the face of the bolt nose provides a seal against the bottom of the counter bore on a trued or well-made action. I had two 700 actions trued by Krieger so I'd expect to have a very close fit between the bolt nose face and the bottom of the counter bore. Either way, I use quality components such as Lapua brass, I'm careful with my reloads, I don't push the envelope in terms of velocity and I wear shooting glasses ALWAYS.
The strength issue is a non-starter for me. Just compare the bolt faces and noses of a .223 Rem, .308 Win and .300 Win Mag 700 bolt and you'll realize that the bolt nose plays a minimal role in action strength. In fact, the BO installation puts a lot more steel in the nose than the original design. The undercut for the Remington extractor is removed and replaced with a ring of steel which increases the bolt nose wall thickness.
My only concern with the Sako or M16 extractors is extraction angle and reliable extraction. It's possible that the Tubb 2000 Sako extractor has a better extraction angle (i.e. closer to horizontal) since the extractor is narrower than the BO M16 extractor. Whatever I decide to do and whatever the outcome, good or bad, I'll report back and be completely honest about the results. If it's a disaster, I'll buy a new bolt(s) from PT&G with a bunch of fancy options.
rcmodel's comment about "making a cut for the extractor clearance" got me thinking. After talking with the machinist and a local gunsmith, rather than open the counter bore to 0.785" all the way around, we could make a 60 degree clearance cut in the approximate location shown in the drawing (which is to scale for a .308 Win).
Just to clarify my comment about Remington's "three rings of steel" being marketing hype, looking at the scale drawing above, when a round is fired, the case expands and exerts a force on the chamber walls. The case exerts a force on the bolt face which is supported by the bolt lugs. It's the chamber walls (first ring) and receiver (second ring) that the barrel/chamber are threaded into that contain most of the energy along with the bolt face supported by the bolt lugs. Only the case rim and the thickest part of the case in the region of the primer pocket are contained in the bolt nose and these parts of the case don't expand significantly. So it's my contention that two rings of steel and the bolt lugs do all or most of the work. Remington's slogan could more accurately be "two rings of steel and a couple of bolt lugs" but it doesn't sound as good. Just my opinion and nothing more and I will happily modify my opinion as new facts come to light.
"Action: Bolt action. A far more rigid, cylindrical receiver replaced the earlier flat-bottomed types. Besides adding stiffness, this design provides a greater and more consistent bedding contact area for the action in the stock. Also, a counter-board bolt faced that completely encloses the cartridge head with an unbroken ring of steel. That ring feeds inside the barrel chamber, which is further surrounded by the receiver. the resulting "three rings of steel" create the strongest action made".
I know the feeling, 1,000 gigs of space is used to describe datum as a line every time head space is discussed (argued), to me datum is not a line it is a circle, round hole, the 30/06 round hole, circle measures 3/8, .375, or I can make it any value I choose, my tools, my gages.
3 rings? 2 rings? I do not care, nomenclature, the chamber wall is not a ring, the receiver is a ring, there is a bolt face that supports the case head with nothing more than a hint of a partial ring that aids in guiding the bullet when feed, then there is the counter bored bolt face that surrounds the case head, and is not broken, (That is a ring), the barrel is counter-bored, the counter-bore in the barrel face surrounds the bolt when the bolt is closed, (That is another ring) The counter bore is cut into the barrel, the barrel is threaded into the receiver, the receiver? (That is a ring).
Difference? Case head protrusion, Mauser, average for 10 barrels .110, Springfield (shaped charge design) .090 at the extractor cut, 303 before the gas escape cut on a P14 .000, rim only, None of the rifles mentioned above had case head support, the web (case head) of the case was supported by the bolt face (no ring) and chamber, web thickness for military cases 30/06 .200 +,-, commercial web thickness .260 +, JIC, JUST IN CASE, something went wrong between the bolt face and chamber holes were drilled in some rifles, the holes became know as Hatcher holes. Foreign designers of rifles built gas escape into the design, except the Japanese, did they need it, after all, it was the strongest rifle in the world? Still looking for those cases.
Design, Remington's design for controlling gas escape is about limiting gas escape, gas is a fluid, fluid will flow, gas can be compressed, by design the case head, unsupported, supports pressure as high as 60.000 psi as a column, mistakes can drive this higher, How much pressure (weight) can a column of brass support?
Before you start, do not use .470X4X22/7, the smallest diameter of the column is .409 at the bottom of the extractor, now change the extractor, jack up the load, compress the column, or apply the LEAVER POLICY and leaver the way you founder. You did say you were having extractor problems.
F. Guffey
I know the feeling, 1,000 gigs of space is used to describe datum as a line every time head space is discussed (argued), to me datum is not a line it is a circle, round hole, the 30/06 round hole, circle measures 3/8, .375, or I can make it any value I choose, my tools, my gages.
3 rings? 2 rings? I do not care, nomenclature, the chamber wall is not a ring, the receiver is a ring, there is a bolt face that supports the case head with nothing more than a hint of a partial ring that aids in guiding the bullet when feed, then there is the counter bored bolt face that surrounds the case head, and is not broken, (That is a ring), the barrel is counter-bored, the counter-bore in the barrel face surrounds the bolt when the bolt is closed, (That is another ring) The counter bore is cut into the barrel, the barrel is threaded into the receiver, the receiver? (That is a ring).
Difference? Case head protrusion, Mauser, average for 10 barrels .110, Springfield (shaped charge design) .090 at the extractor cut, 303 before the gas escape cut on a P14 .000, rim only, None of the rifles mentioned above had case head support, the web (case head) of the case was supported by the bolt face (no ring) and chamber, web thickness for military cases 30/06 .200 +,-, commercial web thickness .260 +, JIC, JUST IN CASE, something went wrong between the bolt face and chamber holes were drilled in some rifles, the holes became know as Hatcher holes. Foreign designers of rifles built gas escape into the design, except the Japanese, did they need it, after all, it was the strongest rifle in the world? Still looking for those cases.
Design, Remington's design for controlling gas escape is about limiting gas escape, gas is a fluid, fluid will flow, gas can be compressed, by design the case head, unsupported, supports pressure as high as 60.000 psi as a column, mistakes can drive this higher, How much pressure (weight) can a column of brass support?
Before you start, do not use .470X4X22/7, the smallest diameter of the column is .409 at the bottom of the extractor, now change the extractor, jack up the load, compress the column, or apply the LEAVER POLICY and leaver the way you founder. You did say you were having extractor problems.
F. Guffey
fguffey said:
Was and still am ... I had to remove four cases (of 58) by hand during a match this past Sunday ... one of the cases during one of the rapid fire stages (10 rounds in 60 seconds).
fguffey said:
Under normal conditions the Remington bolt only supports the case head at the bolt face and to a lesser extent in two locations on the rim. The case head free-floats in the "counter bored bolt face" only being in direct contact with the extractor and bolt face but NOT the entire inside wall of the counter bore. In fact, only the case rim makes positive contact with the inside of the bolt nose at two places 180 degrees apart. Most of the 0.150" of the case from the base to the datum "ring" is totally unsupported (see photo). Insert the head of a case into the bolt and see how much play there is.
fguffey said:
A 0.409" diameter column of brass can support something in the order of 8,300 lbs since cold worked cartridge brass has a yield strength of about 63 ksi.
This photo shows a .308 case seated against the bolt face (where it'd be with the bolt closed). Notice that the base of the case is only supported against the bolt face. What the picture doesn't show is that the case has a lot of play inside the bolt face counter bore.
Anyway, I'm still researching this whole thing and haven't decided what I'm going to do yet.
Terminology, regardless of how we think the cartridge fits (loose/tight) the chamber, the portion of the case that is in the chamber is supported. The portion of the case that protrudes from the chamber is unsupported. Remington would say the head of the case in your picture is surrounded with a complete ring of steel, they would tell you I was wrong if I led you to believe the case is supported by the ring. I say the ring around the ring around the ring is not about supporting but containment, alignment and rigidity
The Datum is measured from the shoulder of the chamber back to the face of the bolt, the 308 W datum (circle/hole) is .400 thousands in diameter and is 1.634 from the bolt face, to avoid the ambush, a good case can be made that I am wrong by .005 thousands, again all of my presses and dies have threads, this makes both adjustable, my chambers are not adjustable, I do not have a Savage or 303 British Enfield.
"The M16 style extractor is a done deal on my .308 since the action truing by Krieger has affected extractor performance and a new extractor won't resolve the issue. I'm not blaming Krieger for this .. they did what they were supposed to do".
I assume the extractor worked before Krieger did the action truing, they did what they were instructed to do and now you have an extractor problem. What did they do to the action that would cause an extractor problem? I do not know. What kind of problem(s) could be created by correcting the problem? Changing the integrity of the design may never present a problem unless the head of the case fails for what ever reason, I do not believe you or or anyone else can have it both ways. Should Krieger bundle their work as in truing the action and include improvements or modifications to the extractor? YES! Should they warne the customer? YES!
Case loose in the chamber? The difference between the inside diameter of the chamber and the outside diameter of the case would have no value if the difference was not known when the rifle was built and compared with the same case. The M1 Garand chamber was larger by .0002 or less than a standard 30/06 chamber.
You removed 4 cases the difficult way because the extractor failed? Were the cases difficult to remove? It is said cases expand when fired, seal the chamber and shrink for easy of extraction (.001 or less), if the cases were difficult to remove (drive out) consider the possibility difficulty of extraction is not the extractor. Easy to do with a control feed flat face bolt, on push feed bolts the extractor claw would have to be removed from the extractor to avoid a hole in the face of the bolt, fire 50 rounds with the claw ground off and remove all 50 cases the difficult way, if the cases are difficult to pound out consider the extractor is doing all it can do and is jumping the rim (or cutting through it), or, as you said the case is loose in the chamber, the 'loose' could allow the extractor to jump the rim and if the case is loose in the face of the bolt find out if the face of the bolt has been opened, the bolt face ring should prevent the case from moving away from the extractor.
F. Guffey
The Datum is measured from the shoulder of the chamber back to the face of the bolt, the 308 W datum (circle/hole) is .400 thousands in diameter and is 1.634 from the bolt face, to avoid the ambush, a good case can be made that I am wrong by .005 thousands, again all of my presses and dies have threads, this makes both adjustable, my chambers are not adjustable, I do not have a Savage or 303 British Enfield.
"The M16 style extractor is a done deal on my .308 since the action truing by Krieger has affected extractor performance and a new extractor won't resolve the issue. I'm not blaming Krieger for this .. they did what they were supposed to do".
I assume the extractor worked before Krieger did the action truing, they did what they were instructed to do and now you have an extractor problem. What did they do to the action that would cause an extractor problem? I do not know. What kind of problem(s) could be created by correcting the problem? Changing the integrity of the design may never present a problem unless the head of the case fails for what ever reason, I do not believe you or or anyone else can have it both ways. Should Krieger bundle their work as in truing the action and include improvements or modifications to the extractor? YES! Should they warne the customer? YES!
Case loose in the chamber? The difference between the inside diameter of the chamber and the outside diameter of the case would have no value if the difference was not known when the rifle was built and compared with the same case. The M1 Garand chamber was larger by .0002 or less than a standard 30/06 chamber.
You removed 4 cases the difficult way because the extractor failed? Were the cases difficult to remove? It is said cases expand when fired, seal the chamber and shrink for easy of extraction (.001 or less), if the cases were difficult to remove (drive out) consider the possibility difficulty of extraction is not the extractor. Easy to do with a control feed flat face bolt, on push feed bolts the extractor claw would have to be removed from the extractor to avoid a hole in the face of the bolt, fire 50 rounds with the claw ground off and remove all 50 cases the difficult way, if the cases are difficult to pound out consider the extractor is doing all it can do and is jumping the rim (or cutting through it), or, as you said the case is loose in the chamber, the 'loose' could allow the extractor to jump the rim and if the case is loose in the face of the bolt find out if the face of the bolt has been opened, the bolt face ring should prevent the case from moving away from the extractor.
F. Guffey
rcmodel
Member in memoriam
I worked on one blowed up 721 years ago in which the bolt could not be opened.
The owner beat on the bolt handle until he peeled it off the bolt body where it was silver-soldered on.
The only option was to take the barrel off to get the case out, to get the bolt body out of the receiver.
It was found that the bolt face "ring of steel" had expanded and galded into the second "ring of steel" or barrel shank recess.
That created a tight gas seal, and kept the hot gas from coming out and totally wrecking the action, and probably the shooter.
By every indication, that is what it was designed to do.
There was no damage to the receiver, and a new bolt put the rifle back in service.
rc
The owner beat on the bolt handle until he peeled it off the bolt body where it was silver-soldered on.
The only option was to take the barrel off to get the case out, to get the bolt body out of the receiver.
It was found that the bolt face "ring of steel" had expanded and galded into the second "ring of steel" or barrel shank recess.
That created a tight gas seal, and kept the hot gas from coming out and totally wrecking the action, and probably the shooter.
By every indication, that is what it was designed to do.
There was no damage to the receiver, and a new bolt put the rifle back in service.
rc
fguffey said:
The cases were all extracted from the chamber without any problems but they weren't ejected from the receiver ... they just sat on top of the magazine in the action so I had to waste time removing them by hand. I've even had a couple of cases do a 180 on me and end up sitting on top of the magazine facing the wrong way!
UPDATE:
Last night I managed to persuade our machinist to stay late and help me install a TUBB 2000 extractor in my .308 bolt.
The good news ... the extractor works VERY well with 100% extraction of the 20 empty cases that I tried last night. The extraction angle is perfect (how the heck did that happen?) with cases ejected just above horizontal. The ejected cases don't get anywhere near the windage knob on my Mark 4 scope (a supposed problem with Sako or M16 style extractors). Also, the counter bore is intact for now. I'll be using the .308 in a match on Sunday (about 60 rounds) so it'll be a good test.
The bad news ... the machinist did a horrible job in terms of aesthetics. Maybe he was tired ... maybe he didn't give a crap ... maybe both. The channel for the extractor is a few thousandths wider and more than a few thousandths longer than it needs to be. Regardless, I figured that this would be a learning process so I have a contingency plan. I'll use the bolt for the next few matches (assuming it works properly) while I put together a .705" bolt from Pacific Tool & Gauge. Their bolts are one-piece and don't have the bolt head/lugs silver soldered in place and they don't charge extra for the cuts for Sako or M16 extractors. A local gunsmith can fit the bolt and ream the action for the larger (tighter fitting) bolt which will help during the rapid fire stages. This was an upgrade that I've been thinking about for a while anyway. I'll be welding on a straight bolt handle rather than the dog leg one that Remington uses.
In case anyone's interested, here are the theoretical extraction angles for the Sako and M16 extractors based on part geometry. The actual extraction angle will depend on a number of variables ... I wonder if luck can be considered a variable?
It's all good!
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