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Posted: 10/24/2010 2:09:42 PM EDT
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What torque setting are you guys using to tighten down the barrel nut on a Daniel Defense rail? Also on a Larue rail.....i'm having problems getting the larue to line up with the upper receiver.
Thanks in advance, JH |
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The torque spec is based on using an appropriate anti-seize grease on the upper's threads. If you don't have grease, or not an appropriate grease, it will be much more difficult to get the specified torque. Use a high quality grease that meets MIL-G21164, such as AeroShell 33MS. Don't use axle grease or basically any automotive product, because it will either not have the required ingredients, or have unwanted ingredients that prevent the material from working correctly for this application.
With the right grease, you'll still possibly have to repeat the torque-loosen-torque process several times, but the torque you read will be much more accurate than without any grease or with the wrong kind of grease. |
| I find that it is also very important to grease the bearing surface between the barrel nut and the barrel extension. This really, really helps when you have a long way to go to reach the next hole on the barrel nut. No need to tighten, loosen, tighten, etc. If you don't lube the bearing surfaces, they will start to bind. Lube it, and you wont have any problems. |
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i have to argue the point of not using automovtive grease. I have heard and read from multipul industry people that any type of grease is just fine, and I know they see and assembly more uppers and guns in a day than i will in a life time. The point is to use a grease so that the upper and barrel nut do not gall together, nothing more or magical about it.
Here is a post from yesterday where ADCO states the same exact thing, they are a great company so u know im not just pulling this out of no where. ADCO grease advice Pat |
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Quoted:
I respect ADCO a lot, but almost every automotive grease (all of them I've ever researched) includes graphite. In an automotive application, steel against steel, this is no big deal. When you're applying this sort of material on top of an aluminum part with hardcoat anodizing, graphite can abrade the hardcoat. Graphite is also bad for exposed aluminum in contact with steel, as it can cause galvanic corrosion with even the slightest amount of electrolyte-and automotive greases are designed to tolerate water, so it's possible the grease itself can become an electrolyte. Considering that you can get 14oz of AeroShell 33MS for less than $15 (that's enough for a LOT of barrel nuts!), I'll stick with a grease designed to provide anti-gall, anti-seize, that's got the viscosity expected in the TM's torque numbers, and that is explicitly designed to be used in steel-on-aluminum applications.
i have to argue the point of not using automovtive grease. I have heard and read from multipul industry people that any type of grease is just fine, and I know they see and assembly more uppers and guns in a day than i will in a life time. The point is to use a grease so that the upper and barrel nut do not gall together, nothing more or magical about it. Here is a post from yesterday where ADCO states the same exact thing, they are a great company so u know im not just pulling this out of no where. ADCO grease advice Pat |
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I wont disagree with anything you are saying, but i mean honestly and realisticly, thats going to have to be alot of abrasion by the graphite to get through the spec 2 hard coat anno, and no abrasion should occur due to movement after the barrel nut is torqued into place if you torque it correctly. You are correct about the chemistry aspect as well, (thank god i am a mechanical and not a chemical enginner lol) and in the furture i will probably use some of the grease you suggest as I havent looked into it and never really thought about it before, but I certianly am not worried about any of my previous builds enough to go tear them down and replace the grease.
Pat |
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