Bolt lug lapping

Discussion in 'Equipment Discussions' started by sakofan, Jun 25, 2004.

  1. sakofan

    sakofan Well-Known Member

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    Would someone share with me, the correct way to lap the lugs on a 700 Rem.??

    New rifle, and it seems to be tighter than anyother I have owned.

    TIA...sakofan..
     
  2. SeniorSendero

    SeniorSendero Well-Known Member

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    Mar 23, 2004
    I used lapping compound on the back side of the lugs, insert the bolt back in the rifle and worked the handle up and down til I got 80% contact. Doesn't take long and you don't want to do to much since it will increase your headspace. You normally only need to lap about .0005" to .0008" to get this so it won't get dangerous. You can check this easily by taking a marker(poor mans Dykem) to the back of the lugs and working the bolt handle up and down the same way as lapping. Now just check and see how much ink is left.

    Rinse the area of lapping compound well with brake cleaner and clean and swab the bore afterwards.

    Ronnie
     
  3. NorthernSniper

    NorthernSniper Well-Known Member

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    Sakofan, I wouldn't be concerned about the action being tight in fact I would be rather happy! I watched the video called the ultimate sniper the fellow doing the instruction and narating actualy showed a Military sniper rifle and commented as he worked the action that these rifles have a tight action as compared to a standard hunting rifle. Good Luck with the new rifle! [​IMG]
     
  4. sakofan

    sakofan Well-Known Member

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    Thanks guys. Just seems a little tighter than my beloved Sako.. [​IMG]

    Test it out tomorrow. Scope came in. Rings, finally. Sent the first set back. Standard anything and US Optics scopes dont go hand in hand. Hope she shoots well!!..sakofan..Thanks for your posts!! [​IMG]
     
  5. JR

    JR Well-Known Member

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    If you lap your own lugs, do remove the firing pin assembly...then make sure you flush the piss out of the inside of the bolt afterward..

    JR
     
  6. sakofan

    sakofan Well-Known Member

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    Can I use Rem. bore cleaner instead of lapping compound?? It's all I have handy right now...sakofan..
     
  7. Pete Lincoln

    Pete Lincoln Well-Known Member

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    Realy you should remove the barrel, screw in the bolt lapping tool then smear the rear of the bolt lugs, or front of the action lugs with lapping paste( valve grinding paste will surfice). but as i suspect you don't have the means to remove the barrel or have a bolt lapping tool what i suggest you do is, remove the firing pin assy, drive out the pin that locates the ejector and remove the ejector, place a fired case into the chamber and begin lapping, after a few strokes of the bolt handel, remove the bolt and case, clean out the excess lapping compound, cut a brass shim to fit in the bolt face, masking tape will surfice, then put the thing back together again with a little more lapping paste on the lugs, work the bult up and down some more. clean the whole thing out, now get some engineers blue, coat the rear of the bolt lugs, close the bolt on the case and shim, then check out what you have achieved in contact area, if sattsifeid you can stop your lapping process there if not carry on. Its a good idea to try the engineers blue (permanent marker pen will also do) before you begin the lapping, this way you can see the improvement.
    The idea is that rearward pressure from the case and shim (or from the spring loaded bolt lapping tool) cause the lugs to be lapped evenly and inline with the bore. If you just lapp with no rearward pressure the tendency is for the one lug to get more of a lapping than the other, due to thebolt handle bieng on the one side of the bolt.
    you can't beat having the barrel off and the action worked over, then you know all is squared up.
    Pete
     
  8. JR

    JR Well-Known Member

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    Pete,

    What I did was used an old remmy barrel, cut the stub short like, then made a brass plunger stuck in old chamber, with extractor slot, so I could lap the face and lugs at same time...jes screw the thing on til it's tight like, and you have spring pressure against the face of the bolt as you arelapping the lugs with pressure...Can make you one up with the next shipment of nubbins if you want...


    JR
     
  9. Pete Lincoln

    Pete Lincoln Well-Known Member

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    Ive already got same set up mate, the alternative with the case was for someone without the tools to remove the barrel.
    but cheers anyway..
    Pete
     
  10. Daddy Justin

    Daddy Justin Member

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    I was searching for something on bolt lapping and I found it. My question is will this make a big improvement in accuracy? I have a Mark V in 30-06. There are only 6 locking lugs and as best I can tell, only 5 are making any contact.
     
  11. jmden

    jmden Well-Known Member

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    Sakofan,

    My take on it would be to get 'Accurizing the Factory Rifle' by McPherson and follow his advice and directions. You should use a bolt lapping tool (keeps bolt square to action--Brownells will have this and the lapping compound) and remove the barrel to do the job right or you may be wasting your time. Since the barrel is removed to lap the bolt lugs properly, when you reinstall the barrel you can now lap the barrel to receiver joint making that joint more stable and also decreasing the headspace that was increased by lapping the bolt lugs. Don't go cheap on this. Do it right the first time. Get the book and the proper tools. I do think it made a difference in my 300RUM 700. Along with proper bedding, good light trigger, right load, it'll likely drive tacks more consistently.

    Just remember to be more careful than ever after bolt lapping to lube the lugs properly and often. Apparently, I've read, bolt lugs are more prone to galling once they've been lapped--go figure.

    Daddy Justin,

    Getting that many bolt lugs properly lapped would be very difficult and I think it's one of the reasons some folks shy away from that action. Many of them shoot very well, however--no ultimate truth here... I'd question a reputable gunsmith about it. Might put a post up asking FiftyDriver or Chris Matthews with your quesiton in Bullets, Barrels and Ballistics. Just my take...

    Good luck.
     
  12. boomer

    boomer Active Member

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    I take a empty case and knock out the primer and replace it with a piece of pencil eraser, then put rubbing compound on the back of the locking lugs work the bolt up and down and check it for fit. the eraser just adds back pressure to the bolt without damaging the bolt face.
     
  13. Guest

    Guest Guest

    [ QUOTE ]
    Can I use Rem. bore cleaner instead of lapping compound?? It's all I have handy right now...sakofan..

    [/ QUOTE ]

    Use JB Compound! Works better than valve grinder material! Not nearly as course! Might take just a bit longer....but not much!! /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif