Gunsmithing Savage barrel swap/headspace question

nfoley

Sergeant
Supporter
Full Member
Minuteman
Nov 15, 2010
1,241
156
54
Castle Rock, CO
Okay quick question for you guys familiar with Savage barrel swaps. I have a 308 and 6.5 CM barrel and found on both when I headspace with the go gauges (proper ones of course) the bolt 'almost' closes on the no go gauge. Bolt will close with only about 0.2" before full closing of bolt. I have removed both ejector and extractor to headspace. And like I said both the 308 barrel and 6.5 CM barrel do the same thing. If I screw the barrel in even a touch more bolt won't fully close on the go gauge.
Any one else see this, and is this okay?
Have noticed on my remington 700 the bolt closes fully on go gauge and only about half way with no go gauge.
Hopefully I am being too paranoid...
 

E. Bryant

STABILITRAK ACTIVE
Supporter
Full Member
Minuteman
  • Oct 25, 2010
    3,922
    4,351
    MI
    Re: Savage barrel swap/headspace question

    My (limited) experience with rebarreling Savage actions is that a bolt which closes properly on a "go" gage is nowhere near to closing on a "no-go" gage.

    I'd start by cleaning everything very thoroughly, with special attention paid to the gages, bolt face, and locking lug surfaces. Just a ever-so-small bit of dirt on one of the lugs could cause headaches during the headspace operation.
     

    nfoley

    Sergeant
    Supporter
    Full Member
    Minuteman
    Nov 15, 2010
    1,241
    156
    54
    Castle Rock, CO
    Re: Savage barrel swap/headspace question

    That's a good thought - will do a thorough cleaning and retry.
     

    m1k3

    Sergeant
    Full Member
    Minuteman
    Sep 12, 2008
    583
    4
    San Angelo, TX
    Re: Savage barrel swap/headspace question

    Clean everything as stated above first.

    Check to make sure the back of the lugs are clean, that the go-gauge is clean, etc. Check to bolt to make sure it is closed all the way on the go-gauge.

    When placing the barrel on, put hand tight against the Go-Gauge. Then hand tighten the barrel nut in place. Go-Gauge should still be pretty tight. When you torque the nut, it will normally pull the barrel forward a little bit (with stock savage threads about .002-.004") and give you just enough clearance. Be careful that when you tighten the nut that the barrel or action doesn't twist on you. When all tightened up the go-gauge should fit just right and adding a piece of thin tape or tissue paper to the back of the Go-gauge will keep the bolt from closing. Check several times with go-gauge and possibly a fired case to make sure it looks alright.

    Shoot me a PM if you need any more help.

    Mike
     

    AXEMAN

    General Nuisance
    Full Member
    Minuteman
    Sep 17, 2009
    5,039
    2
    kansas, topeka
    Re: Savage barrel swap/headspace question

    i found a good video on youtube that explained it when i did my swap
     

    tomcatfan

    Sergeant
    Full Member
    Minuteman
    Nov 22, 2010
    832
    485
    37
    Southern MD.
    Re: Savage barrel swap/headspace question

    In my barrel swap, I put the go guage in my bolt and screwed in the barrel until it wouldn't screw in any more. I then screwed down my barrel nut and tried to chamber a piece of unfired brass. My bolt closed with no problem. When I put the no-go guage in the barrel, my bolt wouldn't close at all. I also double checked this by putting a piece of painters tape on the back of the unfired brass. The bolt also wouldn't close. (not even half way).

    As people said, clean your stuff and try again. If that doesn't work it might be a good idea to mic your guages to see how much difference there is between the two. I don't know what the odds are your guages might be off. I imagine it would be pretty low. But what do you have to loose to just measure them.
     

    nfoley

    Sergeant
    Supporter
    Full Member
    Minuteman
    Nov 15, 2010
    1,241
    156
    54
    Castle Rock, CO
    Re: Savage barrel swap/headspace question

    So cleaned everything thoroughly and same results. Tried multiple times. I checked difference between the go gauge and modified no go gauge and difference is only .002. (Modified no go is simply the go gauge with piece of scotch tape).
    So I called PTG and they stated the difference between their go and no go gauge is .004-.005.
    So, I may be okay. When I double up on the tape and effectively gave it a .004" difference the bolt would only close about 1/2 way.
     

    tomcatfan

    Sergeant
    Full Member
    Minuteman
    Nov 22, 2010
    832
    485
    37
    Southern MD.
    Re: Savage barrel swap/headspace question

    I used painters tape on the back of my go gauge. I don't recommend it, but I did try duct tape and it worked the same as the painters tape. Its important to understand that the point of any tape, paper, shims, etc is to just have your go gauge + .00x legth to make your no-go guage. Also having a good understanding of what headspace is, helps in this process. If you still don't get the warm and fuzzy you can always rig something up to test fire your set up.
     

    stangfish

    Nemesis
    Full Member
    Minuteman
    Mar 1, 2011
    313
    48
    West of East
    Re: Savage barrel swap/headspace question

    The Threads Per Inch or TPI on a Savage is 20 TPI. That is .050 per one full(360*) rotation of the barrel. The difference between the go and the no go is .005 or 1/10th of a revolution or 36 degrees of rotation. That is a lot of rotation to overshoot or lose the tolerences of the go/no go gauge.

    What I believe you should do is touch off on the go gauge and the bolt. Insert the go gauge and close the bolt. Turn the barrel until there is light contact with the gauge. Mark both the barrel and the action with a pencil in a straight line. Snug the barrel nut and then check to see if the lines have changed orientation. If they have lost their alignment you now understand why people use an action wrench.
    The relationship between the barrel and the action needs to be restricted. You will find that the tightening of the nut opens up the headspace gap between the go gauge and the boltface and keeps the bolt from closing on the no/go. Check to see if the bolt will close on the no/go. Some of the tape methods I am hearing scare me. Mostly for accuracy issues but head seperation is possible as well. anytime you use tape or something as a shim, measure its thickness with a mic or at the least with a caliper to verify that it is of an acceptable dimension. As a reference a piece of notebook paper is .0035 YMMV
     

    2156SMK

    Sergeant
    Full Member
    Minuteman
    Jun 8, 2009
    729
    0
    47
    Los Angeles, CA
    www.caprc.com
    Re: Savage barrel swap/headspace question

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Stangfish</div><div class="ubbcode-body">Some of the tape methods I am hearing scare me.</div></div>

    Yeah, the idea of using tape on a go gauge just to save the cost of a no-go gauge is pretty risky when you consider the cost of a no-go gauge and the potential dangers of incorrect headspace...
     

    turbo54

    Mr. 7mm
    Full Member
    Minuteman
    Dec 10, 2010
    4,999
    14
    41
    Michigan
    Re: Savage barrel swap/headspace question

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 2156SMK</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Stangfish</div><div class="ubbcode-body">Some of the tape methods I am hearing scare me.</div></div>

    Yeah, the idea of using tape on a go gauge just to save the cost of a no-go gauge is pretty risky when you consider the cost of a no-go gauge and the potential dangers of incorrect headspace...
    </div></div>

    Well, that's how LOTS of top-flight gunsmiths do it.
     

    AXEMAN

    General Nuisance
    Full Member
    Minuteman
    Sep 17, 2009
    5,039
    2
    kansas, topeka
    Re: Savage barrel swap/headspace question

    they use scotch tape, not duct or painters tapes. good quality clear scotch tape is what the guy used on the instructional video i found on youtube. its supposed to be 0.002" and thats how i did mine. works fine
     

    tomcatfan

    Sergeant
    Full Member
    Minuteman
    Nov 22, 2010
    832
    485
    37
    Southern MD.
    Re: Savage barrel swap/headspace question

    Just for clarification, I did mic my painters tape before I used it. Painters tape is just paper with adhesive on it. Duct tape is a little different as it has threads running through it and does not have a uniform thickness. I admit I wouln't recommend duct tape. I appologize for putting it in my post. But for those of you who do use scotch tape, wouldn't that be a little thicker than something like painters tape?

    If people agree that scotch tape is ok, is there a reason painters tape wouldn't be as long as its less than .005" thick?
     

    2156SMK

    Sergeant
    Full Member
    Minuteman
    Jun 8, 2009
    729
    0
    47
    Los Angeles, CA
    www.caprc.com
    Re: Savage barrel swap/headspace question

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">Well, that's how LOTS of top-flight gunsmiths do it. </div></div>

    That makes them less than top-flight in my book.
    If you are too cheap to buy proper gauges, AT LEAST use steel shim stock...
     

    turbo54

    Mr. 7mm
    Full Member
    Minuteman
    Dec 10, 2010
    4,999
    14
    41
    Michigan
    Re: Savage barrel swap/headspace question

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 2156SMK</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">Well, that's how LOTS of top-flight gunsmiths do it. </div></div>

    That makes them less than top-flight in my book.
    If you are too cheap to buy proper gauges, AT LEAST use steel shim stock... </div></div>

    I'm not going to name names because I don't want any well-respected smiths reputation tarnished... ...but I think you'd be surprised to learn who uses the scotch tape method.

    It's not a case of "being cheap". It's a case of it WORKS. I'd argue it's smarter than keeping dozens of easily lost nogo gages around, AS WELL as being able to indicate a a tighter HS measurement. Nogo's are usually go + .004, while the tape is .002. Better all around as far as I'm concerned.
     

    2156SMK

    Sergeant
    Full Member
    Minuteman
    Jun 8, 2009
    729
    0
    47
    Los Angeles, CA
    www.caprc.com
    Re: Savage barrel swap/headspace question

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">It's not a case of "being cheap". It's a case of it WORKS. I'd argue it's smarter than keeping dozens of easily lost nogo gages around, AS WELL as being able to indicate a a tighter HS measurement. Nogo's are usually go + .004, while the tape is .002. Better all around as far as I'm concerned. </div></div>

    Gauges are not "easily lost" if you are organized like you should be.
    I have perhaps 40 to 50 of them, all organized in a few plastic compartmented boxes.
    I don't fear them getting lost.

    I have 7 gauges for headspace on a 308:
    1.630 (go)
    1.631
    1.632
    1.633
    1.634 (no-go)
    1.636
    1.638 (field)

    No amount of logic can somehow make out the use of tape or shims as a better solution than dedicated gauges.
    Do you know how thick your tape is when you are camming a bolt closed?
    Here's a hint, it's not the same as when you were measuring it with calipers or a micrometer...
    I know how long my steel gauges are as I have the measurment tooling to qualify them regardless of what may be laser engraved on them.

    Its not about doing something so that it just "works".
    It's about doing it the best.

    So let's just be honest.
    It IS about being cheap.
    Otherwise, those "top flight" smiths would use dedicated gauges...
     

    stangfish

    Nemesis
    Full Member
    Minuteman
    Mar 1, 2011
    313
    48
    West of East
    Re: Savage barrel swap/headspace question

    Listen, If you want to use tape go ahead. There are usually a series of mistakes made in order to get to the head seperation. I know, I have the t-shirt. If you feel good about it do it. I just read the duct tape thing and I'm like...oh shit, this dude ain't got a clue about tolerences. Now every newby is going to start spreading the duct tape formula for setting headspace.

    If you reload and use a case headspace(HS) gauge, verify that you're in tolerence and go. Full length sizing can be the culprit if you are not checking the case HS. If you are on the long end of saami specs and you resize to under saami specs you have poor accuracy, blown or shifted primers and worst case incipient case head seperation.

    good luck my friend.
     

    tomcatfan

    Sergeant
    Full Member
    Minuteman
    Nov 22, 2010
    832
    485
    37
    Southern MD.
    Re: Savage barrel swap/headspace question

    Just for reference sake, I measured my 3M painters tape yesterday again and it was .004" thick. In reality if you want to spread a nice uniform layer of spooge on the back of your go guage, as long as it is uniform in thickness, is less than .005" thick, and doesn't get crusty and flake off during head spacing you will be good to go.

    Now at the end of the day I'm not building and selling rifles. I have zero reputation as a gun smith and I wouldn’t even remotely consider myself one. Sure I can headspace a savage rifle (easy as hell to do) and bed a rifle here and there, but I am a novice gun enthusiast. I’m the kind of guy who would rather do stuff himself rather than paying someone else to do it for me whether its tuning my 1911, building an AR, or building a savage. I’ve broken some stuff and I’ve busted some knuckles, but I’ve also learned a lot in the process. So it has been more than worth it. There are a lot of people out there just like me who want to dabble around in the stuff just because they can. I don't want to piss in anyone's cornflakes. I know professionals know a lot more than me, I just know sometimes it helps having people share what works for them, especially in forums like this.
     

    hdbiker1

    Sergeant
    Full Member
    Minuteman
    Dec 3, 2010
    515
    0
    69
    SW Wa
    Re: Savage barrel swap/headspace question

    Personally I use scotch tape and find no reason to buy a no-go gauge, unless someone could show justification that will sway me otherwise. But I don't do this for a living either.
     

    nfoley

    Sergeant
    Supporter
    Full Member
    Minuteman
    Nov 15, 2010
    1,241
    156
    54
    Castle Rock, CO
    Re: Savage barrel swap/headspace question

    Got a no go gauge and noticed it is .004" longer than the go gauge (vs .002" increase measured with scotch tape on the go gauge). Now bolt closes little less than half on the 'real' no go gauge. Sounds like I am good to go - will be shooting this weekend to see how it does.
    I appreciate all the input and help from you all.
     

    jeffm

    Sergeant
    Full Member
    Minuteman
    Apr 17, 2001
    238
    2
    West Virginia
    Re: Savage barrel swap/headspace question

    I rented a go and no go for $24. Money well spent, the rifle shoots great. Cheaper than buying a go and tape.
     

    nfoley

    Sergeant
    Supporter
    Full Member
    Minuteman
    Nov 15, 2010
    1,241
    156
    54
    Castle Rock, CO
    Re: Savage barrel swap/headspace question

    Got to shoot it this last weekend and had excellent results. Accuracy was 1/2 MOA at 113 yards, and brass looked great (factory 140 amax). Shot to 850 yds on steel with great results. Now just need to get out and shoot it some more...