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+--- Thread: Side charging upper woes??? (/showthread.php?tid=11307)
Side charging upper woes??? - customcutter - 05-14-2016
I finally started back on my side charging upper for my next build. I machined the slot in a thin wall upper without any problems.
Then I proceeded to try and modify the bolt carrier to drill and tap it to add a bolt handle. It is a nickle boron bolt carrier that I picked up at a gun show a few years ago. I ground the NB off in the area where I was going to do the machining. Grabbed a cheap chinese Tin coated 2 flute end mill and tried to mill a flat surface. No dice. Anyone have any idea how hard, what Brinell or RC the bolt carrier should be. I don't want to try with another mill, until I'm sure the mill is capable of cutting it. All I did was polish the stainless steel, where I had ground the NB coating off.
Thanks in advance.
CC
Side charging upper woes??? - rwh - 05-14-2016
Most carriers are 8620 steel. Case hardened 8620 is around RC 61 or 62.
Side charging upper woes??? - mongoosesnipe - 05-14-2016
just grind a little flat spot big enough to start the drill bit you don't really need a large milled flat area
Side charging upper woes??? - ricsmall - 05-14-2016
CC,
I drilled mine with a solid carbide drill bit, 2 straight flutes I think. If it's hardish, those end mills don't like a plunge cut that much. Take the tapping slowly, it's tough stuff.
Richard
Side charging upper woes??? - mongoosesnipe - 05-14-2016
i have the lar ops side charger billet upper used in my current grendel configuration i honestly feel its more of a novelty in an ar15 and doesn't really improve anything other than a little less gas when surpassed as the ops does not use a charging handle at all and there is a plug in the back of the receiver
Side charging upper woes??? - customcutter - 05-14-2016
I grabbed a 3/8" 4 flute carbide end mill and milled off a flat spot about 1/2". Spot drilled it and then drilled it through with a #7 drill, and tried to tap it. Got the tap started, and got about half way through pretty easy, then it got tough again. I've tapped .040" titanium with 0-80 taps, so I'm familiar with breaking taps. About an hour later I had sheared the leading teeth off of one tap and gotten maybe one more turn with a second tap before giving up. I put a 1/4-20 allen head bolt in it and managed to screw it in until it bottomed out near the inner wall. Now to make another bolt handle, got the measurement off slightly on the first one and when I drilled the through hole for the 1/4-20 bolt, it cut off the extension that held it off of the carrier. AARRRRGGGHHHH!
Side charging upper woes??? - SG4247 - 05-15-2016
I use a carbide drill and spotface.
Then, i use several hss taps with lots of moly lube. This takes time, if you rush it, the tap will fail. When the leading cutters on the tap start to roll over, chuck it in the trash and use a new one. Usually takes three new taps to do the job.
SG4247
Side charging upper woes??? - am4966 - 05-16-2016
I know you guys like to do your own machineing, but I have found that Precision Firearms side charger bolt carrier is cheaper that others. Then other brands of Side Charging uppers are cheaper. So it's less than the 360.00 you see for most. Personally I've been thinking about going with the side charge upper. But I'm not sure yet, since I need a way to run the gas. Due to using a silencer and I'm trying to figure out the best and less expensive way to do that.
Side charging upper woes??? - customcutter - 05-16-2016
am4966 Wrote:I know you guys like to do your own machineing, and I'm trying to figure out the best and less expensive way to do that.
It's easy buy a cheap $50-60 upper, and a $3,000 milling machine, and a couple a grand worth of tooling to go with it, then you get to play with it and ruin parts and tooling till you figure it out. Plus there's lots of U-tube video's and forums where you can ask questions and get helpful tips, to help you along the way.LOL
Side charging upper woes??? - rwh - 05-16-2016
If we wanted to save money we could save a lot of money throwing rocks, but only rocks 1/2 inch in diameter or less.
Side charging upper woes??? - Drift - 05-18-2016
I suspect that in just a few months a DIY project like CC is exploring will be the cheapest and easiest and quickest way of obtaining an AR in any configuration.
Side charging upper woes??? - am4966 - 05-22-2016
Drift Wrote:I suspect that in just a few months a DIY project like CC is exploring will be the cheapest and easiest and quickest way of obtaining an AR in any configuration.
Yeah after I typed it and few days I had been thinking. Hey goof ball it's cheaper to do it yourself! I had a complete facepalm moment, lol. Just hope you get it figured out soon CC I'm curious to what it'll look like.
Side charging upper woes??? - customcutter - 05-26-2016
I'll post up a pic when I finish the bolt modifications. Drift's comments are in regard to 2nd Amendment Rights and the upcoming election. Right now I have his billet side charge upper that I used for measurements as far as length of stroke, placement of the bolt handle, etc. Mine is a light weight slick side upper, so I'm a little worried about accuracy issues with it flexing, but we will see....