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Posted: 7/21/2008 5:27:36 PM EDT
| who has the cheapest Chrome Carrier assy. or is it best to just stick away from it and get the standard? |
By the manufacturer. DPMS is low end and does not have a good reputation. No-name chrome carriers are probably DPMS. Young Manufacturing is high end and has an excellent reputation. But they cost a bit more. Not too much, but the difference is worth it. |
You can spot a DPMS POS easily enough. It has a "D" on the left side, and is full of tool marks and gouges. 
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This is a "cut & paste" from another thread:  This statement comes from improperly applied hard chrome, any plater who has ANY experience with applying hard chrome know the proper procedure to deal with hydrogen embrittlement that can occur during the plating process. Hydrogen Embrittlement Is a process resulting in a decrease of the toughness or ductility of a metal due to the presence of atomic hydrogen. Hydrogen embrittlement has been recognized classically as being of two types. The first known as internal hydrogen embrittlement, occurs when the hydrogen enters molten metal which becomes supersaturated with hydrogen immediately after solidification. The second type, environmental hydrogen embrittlement, results from hydrogen being absorbed by solid metals. Hydrogen embrittlement is a major cause of fastener failure. Prevailing thought is that steels with Rockwell hardness above C30 are vulnerable. The phenomenon is well-known although the precise mechanism has eluded extensive research. A number of proposed mechanisms have been proposed, and most have at least some merit. Current thinking is that the susceptibility to hydrogen embrittlement is related directly to the trap population. Generally, hydrogen embrittlement can be described as absorption and adsorption of hydrogen promoting enhanced decohesion of the steel, primarily as an intergranular phenomenon. Electroplating is a major cause of hydrogen embrittlement. Some hydrogen is generated during the cleaning and pickling cycles, but by far the most significant source is cathodic inefficiency, which is followed by sealing the hydrogen in the parts. Baking must be performed on high strength parts to reduce this risk, and the ASTM, in 1994, issued a specification for baking cycles, as shown below. For the plater, having to adhere to the post plating baking cycles is mandatory to certify meeting the mil specs.  When it is improperly applied it can make steel VERY brittle! DANGEROUSLY BRITTLE! Hydrogen embrittlement has been known about for decades, any shop that currently does hard chroming should be very familiar with this and also be aware of how to prevent it. If your concerned, follow the chart and bake it out! There are numerous platers who cater to the firearms industry and know the proper plating procedures. Accurate Plating Checkmate Plating Metalife Plating To mention just a few. If you purchase a Young carrier & bolt that is all ready plated you don't have a damn thing to worry about. PursuitSS |
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