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    • #23798
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      This started life as a Blackthorneproducts.com kit as an A3 kit .
      I shot about a box and a little bit of factory ammo ,I can’t believe people actually shoot 100 every trip at those kind of prices . I bought a little bit of 1x brass and loaded a few Hornady 120SST with 2 preferred powders and 1 with high hopes . The rifle turned 2 1/2-3 inches with all loads at 100 yd . I blame at least .5 in on the operator and my familiarity with the platform. After shooting several load work ups with a NOE 279-124 fp in .5 gr steps I went back to shoot the steps in .2 steps that showed the most promise. Everything just fell apart and got worse as I went along . No leading, 2 brushes and a dozen wet/dry patches and clean ……. this lead to learning more about the platform than what I knew from assembly. Off with the A2 fore end, great , a big black line from the gas tube rubbing. That lead to the El Cheapo free float tube kit . With that under way the flash hider was removed it get that big ugly A3 gas block front sight off . For those not aware the A2/3 M4 flash hider comes in 22 and 30 cal and typically resides with an 1/8 in off the muzzle and crown with a .320 x .490 x .128 shoulder/groove/gap that allowed the crown to become a gravel road . There are lots of choices for a fix . Mine was to cut the cut the shoulder out and add threads . A gentleman volunteered his services . While I was waiting I went back and shot a jacketed load that shot well . The free float and getting the gas tube lined up to a nil contact closed the group to a functional 2″ . Well then I noted that the case mouths had a line in spite of being under allowed length . The cases are now trimmed to 1.770 . The NOE Bullet seats out to maximum magazine length . Another thing of note is that the 124 rating of the NOE is a little short as it weighs in at 129 gr and occupies less case than the SST . Cast from water dropped WW/1-20 @ 75/25 it will go to 2400 fps with Hornady checks. A member was kind enough to run a set loads through Quick Load with a 42 kpsi limit . It was a great guide ….. it missed a little with IMR 4350 the estimated 105% load actually had room for 126% .

      I was at last able to shoot the loads with the most promise .
      FC commercial brass from 115 gr FMJ trimmed 1.770
      CCI No41
      23.6 gr H322 new lot June 2015
      NOE 279-124 @ 129 gr 131 with check and lube .
      My Darrs lube ( 14 oz Vaseline, 16 Oz of paraffin, 3 tbsp STP )
      Seated to 2.2285
      1.27 outside of the circle

      No pictures for proof this time as I have a sizing tweek and more than 3 rounds for valid groups .
      A last note this is the 1st time I’ve gas checked a bullet , wow that makes it way too easy, and after the 1st 100 or so rounds I saw zero suggestion of leading in the gas tube, block,or bolt and carrier a sharp contrast to the paper patched 200gr bullet in an sks.

    • #23800
      Goodsteel
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      Do keep us posted Richard. Pictures are definitely preferred, as are ten shot groups.
      If you would like to borrow my chronograph, just say the word and it’s in your hands in a couple days. My dime.

    • #23804
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      I have a Chrony . This is a result of several months of work with this particular rifle . The final well mostly final load is within a velocity flat running within 2 .5 gr steps from 2075 to 2140 . It should looking at baseline groups be 1 of the more stable loads . I am actually well pleased with this because the original factory loads and even work ups with good jacketed loads offed larger groups and just slightly faster loads with a lighter bullet . While tha AR isn’t touted as a cast platform it can be successful. I think the 6.8 cartridge is 1 of those fluke cartridges that may well accidentally join the ranks of the preferred cast cartridges. It has just enough case to get a full case load under the heaviest /longest bullet the twist will manage in what is becoming a standard barrel .

    • #23817
      Goodsteel
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      Very very interesting. I’ll have to look into that cartridge further. Oh, and the AR is walking right into the world of cast bullets with big strides. People like the 300BLK, but they want something more along the lines of what you are doing.

    • #23908
      Taco Bill
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      I’ve had a RRA 6.8 spc II for a couple years now and Love it.
      Tried cast in it but having to keep velocities lower because of leading , I was never able to get it to cycle.
      But now I’m going to try them with PC so I can run them faster and get them to cycle the gun.
      Too cold to experiment now, but as soon as I get some PCed and loaded I will post results

    • #23926
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      A couple of thins about my particular rifle 1st the chamber is short at the neck. I don’t know if the is common or motel . It also has a full shoulder the end result is that it is practically an AI case in this case I doubt it makes enough difference to add .1 gr of even 10x all of my brass is set at 1.770 . 10x shot well but gets spikey at the top loads and there really isn’t data for 130 gr bullets. H4198 should be the ticket but would need an adjustable gas block .while working up that powder I hit a point where the next step failed to hold open but cycled . It would be an excellent choice for a rifle length gas . Mine is a mid- length . I want to try the bullets as cast ,they drop at .279 .I’ve sized at 278 for mine as it is 270 x 277 and I had the 278 sizer for 7mm PP cores . I settled with H322 because it showed the best promise in half gr steps .

      My rig is Melonited. I didn’t know what that was either but it is US GI so it has to be good . Right ? It is a simple process that falls into a catagory of ammonia case hardening and is affected like black chrome. The more you work it the slicker it gets ,but expect it to look like parkerizing at 1st sight . The barrel is like a mirror and the chamber is like really smooth parkerizing. With bronze antiqued highlights, but it’s smooth and doesn’t hang so I’m running with it.

    • #23930
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      A couple of thins about my particular rifle 1st the chamber is short at the neck. I don’t know if the is common or motel . It also has a full shoulder the end result is that it is practically an AI case in this case I doubt it makes enough difference to add .1 gr of even 10x all of my brass is set at 1.770 . 10x shot well but gets spikey at the top loads and there really isn’t data for 130 gr bullets. H4198 should be the ticket but would need an adjustable gas block .while working up that powder I hit a point where the next step failed to hold open but cycled . It would be an excellent choice for a rifle length gas . Mine is a mid- length . I want to try the bullets as cast ,they drop at .279 .I’ve sized at 278 for mine as it is 270 x 277 and I had the 278 sizer for 7mm PP cores . I settled with H322 because it showed the best promise in half gr steps .

      My rig is Melonited. I didn’t know what that was either but it is US GI so it has to be good . Right ? It is a simple process that falls into a catagory of ammonia case hardening and is affected like black chrome. The more you work it the slicker it gets ,but expect it to look like parkerizing at 1st sight . The barrel is like a mirror and the chamber is like really smooth parkerizing. With bronze antiqued highlights, but it’s smooth and doesn’t hang so I’m running with it.
      A couple of links to the long version of the walk through complete with me falling on my face in mid tutorial
      http://68forums.com/forums/showthread.php?57557-6-8-and-quot-free-quot-bullets-or-casting-on-the-cheap

      http://lee-loader.com/viewtopic.php?f=45&t=1133

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