bolt face convertion

dero338

dero338

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moskito land, absurdistant
I have a sako M995 in 338 lapua which I would like to convert 300wm
I know I have te replace the extractor
I would like to know which process is the most simple/reliable

I have read about époxy a sleve, but I dont realy thrust it
would regular silverbearing solder work well?

any suggestions will be welcome

I am also open to trade the action (its in EE)

for those who want to know why keep this action instead of using a 700clone, well its for its quality of course, but especialy for its 0,140'' longer feed port




and no I am not getting out of 338 lapua, I just received a tac338 and still waiting for barrel and reamer to start the build
 
The boltface for a Lapua is larger than the Win Mag, so the bolthead needs to be replaced, and the barrel. A chamber sleeve, particularly in that high pressure cartridge, is a non-starter. There are so many looking for that particular gun, I would strongly recommend selling it and getting what you want.
 
gabrielguitars said:
The boltface for a Lapua is larger than the Win Mag, so the bolthead needs to be replaced, and the barrel. A chamber sleeve, particularly in that high pressure cartridge, is a non-starter. There are so many looking for that particular gun, I would strongly recommend selling it and getting what you want.
Click to expand...

????
I thought I have been clear in my question, but maybe what seems clear to me is not to others

I am talking about the process of reducing the boltface with a sleeve not the chamber. and I am not talking about barrel at all. the blank is already sitting on the shelf waiting to be chambered and spin on the action

I know the strongest way is to solder the sleeve is to solder it but I have read quite a few that use only epoxy or even sleeve retainer locktite( green)
and before I atempt to do it, I would like to know what kind of solder and rosin combination is best.
 
You're talking about a rather small size reducing ring and not so much a long sleeve. I'd suggest that there's simply not enough surface area for a good joint unless you use one of the higher temperature silver solders that is more like brazing.

But silver soldering the face of the bolt is going to require bringing the bolt up to a dull red heat. And that's going to remove any heat treatment in the metal. So following the silver soldering you'll need to get the part you worked on heat treated. But that means heating to a bright red and quenching as the first operation. And when you do that the solder will melt and the little reduction ring will fall out.

So if you're going to go that far then get someone to TIG weld the face of the bolt then have the weld machined to fit the new case head. And following the machine work get the piece you welded and machined re-heat treated to toughen it up again.

This will require that the filler metal be a suitable alloy so that it CAN be hardened and tempered. Or at the least find out what sort of alloy is used on the bolt and use a filler rod that has comparable hardness and toughness qualities without heat treatment.
 
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Brownell's has a bolt body in stock, item 913-400-089WB , it has a 13mm bolt face, so not sure if that is what you need, or not. I am not where I can measure. They have a Super Mag listed at 13.5mm, so 13mm may be the one.
Either way, if its smaller, it can certainly be opened up easy enough.


R.
 
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The simplest, most reliable way would be to sell the Lapua and buy a Win Mag. Especially as you'd have to convert from a rimless case to a belted case, that's 400ish thou shorter. Not worth the expense.
 
Its not like there is a whole pile of M995 actions laying around. I would buy the bolt I needed, and sell the bolt I didn't need.

R.
 
How much expansion do you think you might see in the perimeter of the base eg below the extractor groove with a cartridge loaded to normal pressure .. hopefully not enough to cause a primer pocket to expand. If thats the load you plan to use I dont think a properly fitted bushing held in place with a loctite designed for bushings would be that much of a problem --- after all - if you examine the face of a mauser 98 bolt the bottom (1/2?) circumference doesnt even contain the cartridge base perimeter... and the protrusion at 3 o'clock is really just to keep the cartridge base pressed against the extractor to facilitate ejection. There shouldnt be that much pressure working laterally (as compared to thrust back against the bolt face) ... just some thoughts
 
IMHO if you insist on your idea then soft solders are the only sensible option for you OP.
They will work at about 600deg F and thats well under 720deg C needed to affect the steel temper.
Enlarging bolt dia might be nessesary so the soldered bushing has at least .030" wall thickness.
Make that bushing (from fairly good steel say C1045) OD about .005" (to .010" max) less than ID bolt for clearance, make sure that bushing is at least .020" higher than nedded and at least .020" smaller dia (or about .500"ID) for cleanup machining. Use muriatic acid to clean it up and presolder that ring. Preheat that bolt to say 500deg F in kitchen range for 1/2 hour secure it upright in vise with the help of wooden blocks, use that muriatic acid to clean that bolt face where needed then place that presoldered bushing on top and with the help of propane torch apply heat to that ring until it sinks in place. Then give it to machinist to do his magic.
It's just that easy....
 
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For $190 US dollars, plus shipping, the fella can get the exact bolt he needs, without worrying about 65,000 psi plus being contained by solder...
Come on guys...
Just because you can, doesn't mean you should.
What would you charge to do that solder job? Would you bet your reputation, and the OP's face, that it will hold? Why take that chance. For $250ish this guy solves his problem, and still has a bolt to sell. The final cost is less than anyone would charge to do that bolt work as suggested.

R.
 
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Rman said:
For $190 US dollars, plus shipping, the fella can get the exact bolt he needs, without worrying about 65,000 psi plus being contained by solder...
Come on guys...
Just because you can, doesn't mean you should.
What would you charge to do that solder job? Would you bet your reputation, and the OP's face, that it will hold? Why take that chance. For $250ish this guy solves his problem, and still has a bolt to sell. The final cost is less than anyone would charge to do that bolt work as suggested.



R.
Click to expand...

You apparently know very little about rifles and stresses on bolts................the existing ring of steel on the boltface holds all the pressure required to contain the 338 LM, soldering a spacer sleeve inside this ring in no way affects the strength or integrity of the original ring of steel, it is just a spacer. To accuse us of risking someone's well being with bad advice is very ignorant of YOU when you do not know what you are talking about.........obviously........
 
How would the sako extractor work with the sleeve? Would it not be still at the original diameter of the bolt?
 
Not that I know a whole bunch about rifles...but the extractors on Sako bolts are fairly forgiving, so, in theory it would be just fine. There is about half a millimetre difference on the bolt face diameter...
I just really can't understand the thinking that always wants a five dollar solution to a twenty dollar problem.
Buy the proper bolt, sell the old bolt, and rock on with zero worries.

R.
 
c-fbmi said:
You apparently know very little about rifles and stresses on bolts................the existing ring of steel on the boltface holds all the pressure required to contain the 338 LM, soldering a spacer sleeve inside this ring in no way affects the strength or integrity of the original ring of steel, it is just a spacer. To accuse us of risking someone's well being with bad advice is very ignorant of YOU when you do not know what you are talking about.........obviously........
Click to expand...

Really curious as to how many bolts you have sleeved in this fashion successfully?
Can you elaborate on the methods used to create this sleeve and have it installed within the existing diameter of the bolt face?

R.
 
anyone who has examined a true "CRF" action will recognize that the bolt face does NOT have to contain the base of the cartridge completely . The sole requirement is for there to be some arrangement to ensure that the extractor doesn't slip of the rim while extracting the round. CRF have a small "lip" and Sako or Remington style generally use a recessed bolt face ( but not always) the installation of a bushing is simply to ensure that the extractor maintains a bite on the rim- it maybe that even without the bushing the extractor will be satisfactory...if the OP "can" find another appropriate bolt ... he should do so.
nobody would suggest this is not the best solution ...but if he can't a bushing is one option. he asked - he was told. now he can chose whatever he likes.
 
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