ARC Shouldered BarLoc review

blbennett1288

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  • Apr 24, 2017
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    It'll be a couple weeks before I have the time to really devote a day to test the repeatability of the BarLoc so I figured I'd go ahead and post my initial impressions and results. I have tested the BarLoc out on three range trips, between 6.5CM and 5.56.

    I am using a Vortex AMG with the micro adjustment zero turrets. I zero the 6.5CM barrel with the micro adjustments and then just used the turrets to adjust for the 5.56 offset.

    Day 1 (Hand tight)
    I simply tightened the barrels down hand-tight. While doing this I noticed that the barrels started to get "hand tight" around the 10' Clock mark. 10-10:30 provided the best bolt feel, but the barrels could be tightened down even further to 11-11:30.

    With this range from 10-11:30 in barrel tightness (~45deg) the zero shifted considerably every time a barrel was changed. In the range of anywhere from 0.5-1.5mils on elevation and windage. I did not take good notes during this time as there was a lot of swapping and adjustments being made.

    Day 2 (witness marks)
    On the second day I used witness marks, made with paint pen, on both sides on the barrel, referencing the chassis. I could not reference the action because of the BarLoc. I could not reference the BarLoc because it's orientation shifts ever so slightly every time.

    6.5CM Zero 8.8E, 9.1W
    5.56 Adjustment +1E, -0.4W


    I switched back and forth a couple times and the zero on the 6.5CM was within +/- 0.5Mils. The 5.56 was within +/- 0.2Mils.

    Day 3 (witness marks, bolt feel, level break)
    On the third day I still used the witness marks but adjusted (within the thickness of the witness marks) based on bolt feel. I also used a bubble level to make sure the breaks were level as another point of reference for repeatability.

    6.5CM Zero 8.4E, 9.1W
    5.56 Adjustment +1.1E, -0.2


    I only switched from 6.5CM to 5.56 and back to 6.5CM as I wanted to get good dope out to 1k on the 6.5CM before the rain came. 6.5CM was still within +/-0.5Mils. The 5.56 was still within +/- 0.2Mils but I added a muzzle break and suspect this had something to do with it.

    Conclusion
    The system works well and is much easier to change barrels as opposed to a barrel nut or conventional action wrench. Some of this error could easily be attributed to me as a shooter. The 5.56 barrel does seem less susceptible to shifts in zero. The only additional procedure I may try is using Go/No-Go gauges when swapping barrels. I will also try leveling the BarLoc after every swap, although I think this will be difficult due to the notch on the bolt end of the BarLoc. Besides that I would suggest using witness marks and re-zeroing the larger calibers after every barrel swap.

    5qQjUOC.jpg


    9Xt9mD5.jpg
     
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    Nice, I would think a rezero will always be necessary, it's not really designed to be all that repeatable given the variables involved. It does however make swaps at the range possible with minimal tools and that's something only the AIs and DTs have been able to do.
     
    Great write up. I look forward to your longterm review.

    BTW, Did you request the logo be engraved on the barrel? Looks don't effect function, but that looks terrible. Is there a reason they had to mill it out so deeply to put that in?
     
    Great write up. I look forward to your longterm review.

    BTW, Did you request the logo be engraved on the barrel? Looks don't effect function, but that looks terrible. Is there a reason they had to mill it out so deeply to put that in?

    I'll put some money on "It was to get rid of an older engraving".

    I was just going to post a question about this very topic. Thanks Bennet for the pics and write up. It seems to me the shouldered barrel is the way to go? What is the downside, or the upside of the nut version?
     
    BTW, Did you request the logo be engraved on the barrel? Looks don't effect function, but that looks terrible. Is there a reason they had to mill it out so deeply to put that in?

    I did not request it, this is standard for this gunsmith, but to my understanding chambered barrels must have the origin located on them somewhere.
     
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    I'll put some money on "It was to get rid of an older engraving".

    I was just going to post a question about this very topic. Thanks Bennet for the pics and write up. It seems to me the shouldered barrel is the way to go? What is the downside, or the upside of the nut version?

    I am not sure if Rock Creek barrels come with an engraving.

    I honestly think the shouldered version is the way to go as it is quicker, requires less tools, and you don’t have to remove the scope or the chassis.

    The only benefit I could see the nut having is that it is a hard stop (you can set it with loctite or a set screw) as opposed to hand tight or witness marks. Therefore the zero has less shift. I do not know this for certain and is speculation. Even if that is true I do not think this benefit outweights the aforementioned three pro's of the shouldered version. At max it took 6 shots to re-zero; 3 shot group to confirm offset, 3 shot group to re-zero.
     
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    Is that how they do all there barrels? Just asking.
    There have been a couple I have seen that do not have that, but I think they are non-Rock Creek barrels. Both my Rock Creek barrels have that.

    Y'all are a tough crowd to please, if it shoots well, who cares what it looks like. I think it looks pretty slick and gives a good point of reference for the BarLoc.
     
    It'll be a couple weeks before I have the time to really devote a day to test the repeatability of the BarLoc so I figured I'd go ahead and post my initial impressions and results. I have tested the BarLoc out on three range trips, between 6.5CM and 5.56.

    I am using a Vortex AMG with the micro adjustment zero turrets. I zero the 6.5CM barrel with the micro adjustments and then just used the turrets to adjust for the 5.56 offset.

    Day 1 (Hand tight)
    I simply tightened the barrels down hand-tight. While doing this I noticed that the barrels started to get "hand tight" around the 10' Clock mark. 10-10:30 provided the best bolt feel, but the barrels could be tightened down even further to 11-11:30.

    With this range from 10-11:30 in barrel tightness (~45deg) the zero shifted considerably every time a barrel was changed. In the range of anywhere from 0.5-1.5mils on elevation and windage. I did not take good notes during this time as there was a lot of swapping and adjustments being made.

    Day 2 (witness marks)
    On the second day I used witness marks, made with paint pen, on both sides on the barrel, referencing the chassis. I could not reference the action because of the BarLoc. I could not reference the BarLoc because it's orientation shifts ever so slightly every time.

    6.5CM Zero 8.8E, 9.1W
    5.56 Adjustment +1E, -0.4W


    I switched back and forth a couple times and the zero on the 6.5CM was within +/- 0.5Mils. The 5.56 was within +/- 0.2Mils.

    Day 3 (witness marks, bolt feel, level break)
    On the third day I still used the witness marks but adjusted (within the thickness of the witness marks) based on bolt feel. I also used a bubble level to make sure the breaks were level as another point of reference for repeatability.

    6.5CM Zero 8.4E, 9.1W
    5.56 Adjustment +1.1E, -0.2


    I only switched from 6.5CM to 5.56 and back to 6.5CM as I wanted to get good dope out to 1k on the 6.5CM before the rain came. 6.5CM was still within +/-0.5Mils. The 5.56 was still within +/- 0.2Mils but I added a muzzle break and suspect this had something to do with it.

    Conclusion
    The system works well and is much easier to change barrels as opposed to a barrel nut or conventional action wrench. Some of this error could easily be attributed to me as a shooter. The 5.56 barrel does seem less susceptible to shifts in zero. The only additional procedure I may try is using Go/No-Go gauges when swapping barrels. I will also try leveling the BarLoc after every swap, although I think this will be difficult due to the notch on the bolt end of the BarLoc. Besides that I would suggest using witness marks and re-zeroing the larger calibers after every barrel swap.

    5qQjUOC.jpg


    9Xt9mD5.jpg
    Is this the Switch Lug from MPA (saw your chassis) or done by another company?
     
    Is this the Switch Lug from MPA (saw your chassis) or done by another company?
    Patriot Valley Arms did the work. It is American Rifle Company's Shouldered BarLoc and all that has to be done is the barrels cut appropriately for the BarLoc. There is no lug on this version, it is just a collar/clamp in between the barrel and action. There is no work done to the chassis or action, unlike WTO's switchlug system.
     
    There have been a couple I have seen that do not have that, but I think they are non-Rock Creek barrels. Both my Rock Creek barrels have that.

    Y'all are a tough crowd to please, if it shoots well, who cares what it looks like. I think it looks pretty slick and gives a good point of reference for the BarLoc.


    @blbennett1288 of that flat was on the other side of the barrel too, would it be flat for a wrench to hold?

    Since I can’t use a barloc with my XLR Carbon maybe I’ll ask PVA to flat both sides if it’s marked the same way.
     
    The flat part is solely for engraving. There is no barrel wrenches involved with the shouldered BarLoc.

    I understand that. I was looking forward to a Barloc also but have learned it won’t work with my chassis.

    I was simply asking if that flat for the engraving was on both sides of a barrel could you fit a wrench on it.

    Unless I switch chassis I will have to stick with simple shouldered barrels or a nut type system.

    Thanks for the help. Great looking rifle.
     
    I understand that. I was looking forward to a Barloc also but have learned it won’t work with my chassis.

    I was simply asking if that flat for the engraving was on both sides of a barrel could you fit a wrench on it.

    Unless I switch chassis I will have to stick with simple shouldered barrels or a nut type system.

    Thanks for the help. Great looking rifle.

    Thanks. The entire area is recessed so you could not get a wrench on it, look at the first picture closely and you will see what I mean. @reubenski has a guy that puts two flat spots on the muzzle end of his shouldered barrels so he can change barrels with a wrench. Maybe contact him asking for his smith? Below is a picture of his rifle.
    reubenski TL3 switch barrel 2.jpg
     
    Thanks. The entire area is recessed so you could not get a wrench on it, look at the first picture closely and you will see what I mean. @reubenski has a guy that puts two flat spots on the muzzle end of his shouldered barrels so he can change barrels with a wrench. Maybe contact him asking for his smith? Below is a picture of his rifle.View attachment 6906897


    Thanks that is sweet! I’ll bet Josh can do that for me. I’ve been waiting a long time a little longer won’t hurt if he can make it happen.

    That or I sell for an MPA.
     
    What do you mean adjust by bolt feel? I can't see how you are going to feel the difference in a shouldered barrel? Are you usuning brass that the shoulder hadn't been bumped on?
     
    What do you mean adjust by bolt feel? I can't see how you are going to feel the difference in a shouldered barrel? Are you usuning brass that the shoulder hadn't been bumped on?

    In the 45 degrees you have between the 10-11:30 position the bolt cocking in the 11-11:30 position is noticably more than the 10-10:30 when working the bolt.
     
    BTW, Did you request the logo be engraved on the barrel? Looks don't effect function, but that looks terrible. Is there a reason they had to mill it out so deeply to put that in?

    It was cut that way to get the customer his barrel, meet federal requirements for marking the barrels and not wait the next 3 weeks for our Fiber Laser to show up.

    The laser is here now, so future barrels are being burned.
     
    Thanks that is sweet! I’ll bet Josh can do that for me. .

    You guys must have a camera up in the shop... I'm in the midst of updating the muzzle threading programs for the new lathe to allow us to cut a hex on the barrel for shooters to order exactly that.

    Some don't want it, some have asked. I have the cutter ordered to make the undercuts in the same setup as the muzzle threads.
     
    You guys must have a camera up in the shop... I'm in the midst of updating the muzzle threading programs for the new lathe to allow us to cut a hex on the barrel for shooters to order exactly that.

    Some don't want it, some have asked. I have the cutter ordered to make the undercuts in the same setup as the muzzle threads.

     
    I’ve heard.

    Reference, below is my PVA barrel.

    We've had several variations of engraving trying to get something to make everyone happy. Long story short that doesn't work.
    I tried the salt/acid electrochem etching... it's OK but not great.
    Then prefits come along and I had guys return barrels because the stenciled etch mark didn't line up inside their RPR handguard and "for the money spent this should look..." You get the idea.
    So we put them on the breechface such that it still meets federal regs but doesn't show outside the action and therefore the clocking of the mark is not important. This is the way that Criterion did it for YEARS... I figured there couldn't be a complaint about that because it was established in the market. I believe they're either roll stamping or lasering them now.

    Then we had complaints about that because guys couldn't tell what barrel they had on the rifle while it was sitting in the safe so they had to take it out, open the bolt and look down it.
    Someone actually called the ATF to bitch because he said it wasn't in compliance. That spawned a compliance check and a day and a half down in the shop so that they could check everything over engraving on barrels. Turns out it meets their requirements and we had no violations but I couldn't do anything except host the inspecting agent and showing them our process...


    So then we started milling them as seen above. In some cases it lines up, in some cases it doesn't, but it meets federal regs and when we started it I couldn't afford 40+ grand for a 50W fiber laser. On TL3's we have an artifact so that I can at least clock the mark appropriately.


    With the Hancocks, Nucleus barreled actions and everything else we're doing I bought the laser last month and it arrived this week. Thankfully the bank decided they would back it and so it costs us a little over 800 bucks a month to laser engrave barrels.

    As I said above, the short answer to a long story is that it doesn't seem like engraving should be a big deal on a prefit barrel but yet it's proven to be one. At this point I'm marking the barrels to federal code by using a deep laser mark and we're done. There is, to my estimation, no better way to mark barrels and where it clocks up is where it clocks up for prefits. So, we're done experimenting and I've spent as much on marking barrels as I did on my first CNC lathe to actually cut them.

    I can't see a better way to do it, we've sunk the cost and bought the best thing we could for marking barrels. There are lots of ways, it has proven that no way makes everyone happy. With a prefit barrel that uses a barrel nut on broad spectrum of actions there's always a roll of the dice where it will line up. Unless someone wants to send their action in for me to headspace the barrel to it and then mark it there's no way around that.
     
    Leave it up to the RPR guys lol


    You say that so easily. Almost like you wouldn’t raise hell if you paid good money for a custom barrel and you one marked with an electric pen (among other issues).

    Sorry for crapping on the thread, blbennet. Just curious if this was a specific request.
     
    You say that so easily. Almost like you wouldn’t raise hell if you paid good money for a custom barrel and you one marked with an electric pen (among other issues).

    Sorry for crapping on the thread, blbennet. Just curious if this was a specific request.

    I have custom rifles with the electro chem etching and it doesn't bother me one bit. Also have some that look like a stamp. I don't really care what it looks like or if it's not indexed perfectly. Some people are going to bitch regardless of what you do which is why I would never own a business. You can't make everyone happy and I'm sure even with a high dollar machine someone will still bitch. My buddy had a rifle built and the Smith stamped it 6.5 creedmore. We laughed about it rather than whining about it lol
     
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    You say that so easily. Almost like you wouldn’t raise hell if you paid good money for a custom barrel and you one marked with an electric pen (among other issues).

    Sorry for crapping on the thread, blbennet. Just curious if this was a specific request.

    I sent you a PM. If there's something else going on with the barrel that is an issue then we'll take care of it.
    As far as engraving goes, if you need it remarked then we'll change that too if the barrel has to come back for other stuff.
     
    Just a lesson learned that I wanted to pass along. I have started to witness mark the Barloc set screw. I either unknowingly applied 65in-lbs (chassis screw torque) while at the range or it loosened up over the course of a couple hundred rounds (doubtful).

    Long story short, I was checking to make sure everything was torqued appropriately the night before a match and let’s just say I made the decision to torque it to the appropriate 90in-lbs. Things did not go too well.
     
    Just a lesson learned that I wanted to pass along. I have started to witness mark the Barloc set screw. I either unknowingly applied 65in-lbs (chassis screw torque) while at the range or it loosened up over the course of a couple hundred rounds (doubtful).

    Long story short, I was checking to make sure everything was torqued appropriately the night before a match and let’s just say I made the decision to torque it to the appropriate 90in-lbs. Things did not go too well.

    So for clarification, did things break or did your zero skip town for east bumblefuck?

    I have one to put on my Mausingfield once I machine the scope rail so any issues you find helps me when my new Barrel gets in.
     
    Nothing broke, tightening the barloc from whatever’s it was set at to 90in-lbs caused the zero to shift

    Which is odd to me because you are not applying torque to the barrel causing the threads to engage more. You are applying torque to the BarLoc which applys tension to the threads at the same point. So to me you would not think it would not change zero much. At least that is what I thought when I did it lol
     
    That is interesting because tightening the Barloc would not rotate the barrel so run out shouldn't matter.

    I can't wait to get mine for testing.
     
    I spent about 3 hours on Friday testing out the shouldered BarLoc and I feel more confident in these results. I switched barrels 5 times, 6.5CM, 5.56, 6.5CM, 5.56, and 6.5CM.

    6.5CM
    8.65E
    9W

    5.56
    +1E

    -0.2W

    Each time I switched barrels it was within 0.2mils of those numbers which is plenty acceptable and more along the lines of what I expected when I started on this build.

    Picture of BarLoc
    aLYuMdF.jpg


    Picture of conical face
    fFkgkmC.jpg


    Step 1: Swap bolt faces and magazine
    YfpUVxb.jpg

    5lZo5bG.jpg

    Step 2: un-torque BarLoc with 5/32” Allen key
    K1bS3Ti.jpg

    Step 3: remove barrel and clean threads
    GQfqvlM.jpg

    Step 4: apply anti-seize to new barrel
    Km7dCL2.jpg


    Step 5: Torque new barrel to barrel witness marks. Apply 90in-lbs to ARC BarLoc and use alcohol wipes to erase old witness mark and make a new witness mark on the set screw.
    FdvK8h1.jpg
     
    You guys must have a camera up in the shop... I'm in the midst of updating the muzzle threading programs for the new lathe to allow us to cut a hex on the barrel for shooters to order exactly that.

    Some don't want it, some have asked. I have the cutter ordered to make the undercuts in the same setup as the muzzle threads.


    Say wat? Shouldered prefits with wrench flats already milled?
     
    Say wat? Shouldered prefits with wrench flats already milled?
    Working on it.
    It takes a little more than just throwing it in the machine but we're getting pretty close. For TL3's I have it where I'm almost ready to cut it on a customer's barrel... almost.
     
    How close?? I’d like it before mine is done in the shop.
    CHances are that's not reality. We have the vast majority of the Nucleus group buy and Nucleus barreled action barrels done just waiting for the laser work. Ted is sending me a timing artifact to use for finding TDC, that's the only reason we haven't shipped the barrels yet. They are lined up along the wall.
     
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