Gunsmithing I think I made a pretty big mistake ?

Rprecision

Rprecision

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Nov 9, 2011
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Progressive Hell, CO
#1
So I just finished up the machine work on my Remington 700 in 300 Win Mag.

While truing the bolt face I ended up taking off .020 to .025.” This was not intentional, I had a bit fail, rolled and left a grove that had to be removed.

Now my concerns are this:

· Does this present a safety problem?

· Is this going to cause problems now that the extractor is now .025 further forward

· Will the added .025” of firing pin protrusion cause problems.

I don’t know if I should scrap the bolt and start with something new or if this will be safe and functional.

I hate screwing up something


 
#3
Re: I think I made a pretty big mistake ?

That is quite a bit of material removed. Nothing should be weakened structurally but you probably compromised how at least 2 of the bolt assembly components will work reliably.

First thing would be to drop the firing pin into the bolt and check your protrusion. It will probably be too far out of spec and could cause issues with pierced primer cups.

Second thing would be very good possibility that your extractor will not work properly due to so much excessive play between the claw and the new breech face. The extractor may lose control of the case/round during bolt back part of the cycle.

The factory extractor also needs to rest against the breech face so that when your case rim comes into contact with the extractor tooth, it will be forced to flex outward instead of rearward with the case. With the breech face moved that far, the extractor will still be forced to snap over the rim but not until the case rim pushes it 0.025" to the rear every time you chamber a round. This would likely cause the factory style extractor rivet or the spring steel extractor to fail prematurely if it even worked right in the first place.

Replacing the bolt would be the easiest fix.

Option B would be to re-grind the firing pin to adjust protrusion back to spec and possibly install an aftermarket extractor like Mini-16 or Sako with appropriate geometry correction based off of your new breechface.
 
#4
Re: I think I made a pretty big mistake ?

It's flat and true now, how about soldering a shim in and spin it back to spec? I have not done it, but have seen bolts bushed....you could do the same......no?
 
#6
Re: I think I made a pretty big mistake ?

i think it would have been fine with the firing pin protrusion fixed. if the extractor failed replace it with a better aftermarket design.

chuck
 
#8
Re: I think I made a pretty big mistake ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MarinePMI</div><div class="ubbcode-body">How about making a recoil lug to compensate? </div></div>

Are you thinking head space? I think he is more concerned about the bolt face interaction with the cartridge and how deep the firing pin will protrude into the primer and how far out the extractor will extend beyond the rim of the cartridge.
 
#9
Re: I think I made a pretty big mistake ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MarinePMI</div><div class="ubbcode-body">How about making a recoil lug to compensate?</div></div>

The machine work was done to the bolt face moving it further back away from the extractor and closer to the firing pin.

While your right, that would fix the headspace, I opted to wait to chamber until after the new bolt arrives.

I should have just bought a custom action, like I had intended to from the start......sigh
 
#10
Re: I think I made a pretty big mistake ?

Ahhh...gotcha. I mis-interpreted what you original post said. My apologies for introducing confusion into the thread (that's what I get for not reading carefully I suppose).
 
#12
Re: I think I made a pretty big mistake ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rprecision</div><div class="ubbcode-body"> <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MarinePMI</div><div class="ubbcode-body">How about making a recoil lug to compensate?</div></div>

The machine work was done to the bolt face moving it further back away from the extractor and closer to the firing pin.

While your right, that would fix the headspace, I opted to wait to chamber until after the new bolt arrives.

I should have just bought a custom action, like I had intended to from the start......sigh</div></div> ...until the bolt arrives,can be a wrong proposal heli-arc weld (not solder!)the bolt face,restoring the bolt face slightly over the desired dimensions,and recut it ?_ Before surrender,if possible, try to ask to a professional TIG welder..._ good luck!
 
#13
Re: I think I made a pretty big mistake ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: wilecoyote</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rprecision</div><div class="ubbcode-body"> <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MarinePMI</div><div class="ubbcode-body">How about making a recoil lug to compensate?</div></div>

The machine work was done to the bolt face moving it further back away from the extractor and closer to the firing pin.

While your right, that would fix the headspace, I opted to wait to chamber until after the new bolt arrives.

I should have just bought a custom action, like I had intended to from the start......sigh</div></div> ...until the bolt arrives,can be a wrong proposal heli-arc weld (not solder!)the bolt face,restoring the bolt face slightly over the desired dimensions,and recut it ?_ Before surrender,if possible, try to ask to a professional TIG welder..._ good luck! </div></div>

This seems like a totally legit fix. Use crown 220 filler rod.
 
#15
Re: I think I made a pretty big mistake ?

...a real pro-TIG welder can answer, and professionally advise if it's feasible or not_ If says yes,you will be safe and very happy _This way, I have saved a damaged .308 L1A1 bolt_ good luck_
 
#16
Re: I think I made a pretty big mistake ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: hero's machine</div><div class="ubbcode-body">What about heat affect on the lugs? </div></div>

Depending on how it is done, I think it would be ok. I wouldn't just lay a fat bead in there in one shot, I would do it one dab at a time, to keep the HAZ small, and keep the lugs from getting hot.
 
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