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The Bored Tips of a Gunsmith for LR-308 or AR15 Builds

DoomRabbit01DoomRabbit01 Member Posts: 13
edited January 2021 in Politics

So apparently the husband is bored and has decided to con me into transcribing some tips for those new to modifying their own AR builds (or AR10/LR308s). Diving in:

- Study some Nikola Tesla, and then empty your buffer tube of weights. Buy Neodymium 48 weights (you can buy boxes of 100s for a few dollars) of the same size. Drop the first two in in a direction to repel the other one, and the one other to "pull" back against the BCG yet push away from the other weights. What you wind up with is a near negating of the "kick" of almost any round that you fire, and it turns into a 'shove' against your shoulder. This also almost entirely removes the upward travel of your barrel between shots. As the first magnet is pushed back near the other two magnets, they will "toss" the BCG back forward and back into place - faster than the spring alone and ensuring the weapon ALWAYS cycles. As a side note Neodymium 48 weighs precisely the same as Zinc coated steel, so the balance of your weapon will not be thrown off. Good time to note that the aluminum cap on the buffer tube will not allow the BCG to actually get stuck to the magnets, or actually be pulled to the magnets.

- Take a belt sander and shave the back of your BCG to angle towards your buffer, thinning it by half where the impact point is at a steady slope. Polish this with 1500 grit paper afterwards, and then use a paint brush to paint a very thin coating of clear epoxy over where you ground for rust protection and a slick surface. This will drop your friction coefficient by a great deal, with almost no weight loss nor performance of the BCG. Low weight BCGs look neat, but there is a reason the military has never swapped to them... that would be their risk of failure to operate or cycle due to their lack of weight. You can enjoy the same lowered coefficient without losing needed weight, a weight negated by the first tip anyway. This also allows you to enjoy the lessened gas pressure of a mid-length gas system on a carbine length barrel - though if your barrel is setup for a carbine length gas setup use that and leave that kind of change to a gun smith who can move the hole without risking gas system failure.

- If you like the kick provided by the good old fashioned buffer tubes, but don't want to pay for tungsten weights... go to Home Depot, buy a copper ground rod for a house and a 1" hollow copper pipe. Cut the copper pipe to a 1" segment, then use a dremel tool to cut out about 1/8th of an inch of the pipe. Use a 3lb sledge to cold hammer this around the cut out 1" piece of the ground rod, epoxy them together using JB Weld 9200 PSI, let it dry, and replace one of the steel weights with it. You're now near the weight of Tungsten without spending hundreds of dollars on a buffer tube.

- When Fluting a barrel you only need 4 things ... not a fancy CNC Mill. You need Vise Clamps (or even crankable clamps to lock the barrel to a table, a pair of calipers, and a compass. (You can get an entire set of precision measuring tools from Harbor Freight for 10 bucks that are close enough.) Figure out how thick your barrel is on both the front, and back ends (most, especally heavy barrels, are different. Only Bull and Pencil barrels will be near the same.) You want to cut into this by 1/3 of the barrel depth. Now measure how wide you want your flutes. These can honestly be as wide as you want as long as you do not pass that 1/3rd number. Use the calipers to basically draw dots down the length of the barrel, or at least however far down you wish to flute... and then play connect the dots. You can use a level at this stage to ensure they are straight, but if you are just saving weight for yourself you can play with patterns, or who cares about it being 100% straight just for you? Now the 4th item comes into play. Take a Dremel Tool (Walmart makes a good fake Dremel called Hyper Tough that works well enough for someone working on one or two guns, and it can fit all Dremel bits.) with a cutting disc (try to get one of the angle grinder discs, not those little thin snaping discs unless you have a LOT of patience). Divide the 1/3 number in half and cut that deep at a 45 degree angle (you can do this with aforementioned compass with practice). Repeat on the other line and... tada. You have a flute. Granted it will have shape edges, and a sharp bottom, both of which can be fixed with a Dremel Diamond tipped grinder that comes in most every beginning Dremel set, or just a tungsten carbide cutter for 3 bucks at Walmart. At this point you are just rounding off the edges and the bottom. A quick and dirty fluting that will cut weight without cutting into the strength of a barrel... granted if you have a mill with a sliding table you were done three hours ago, but hey.

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More to come later.

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