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Everything posted by 308USK

  1. I had to add a 2nd tungsten weight to my SCS, to get my LR308 working (after a crap-ton of help from the fine folks here [thanks again gang!]). Now my rifle runs like a champ; probably 1000 rounds through it since June 2022 and only a few mis-fires during that initial period of getting the gas & mass squared away.
  2. Gas tube is too short for sure. Gas port is DEFINITELY too small. I'd drill (drill baby drill, as has been said on the forum)...!!!!!
  3. What @shooterrex said! Gas port is too small...and/or buffer spring & weight are incorrect.
  4. FWIW, I had to open up my gas port, so I got a couple of #'d drill bits (#41 and #42) and started small. Taped the drill bit at a point where it would go into the barrel a little ways, but NOT all the way and nick the bottom of the inside of the barrel. (note: I used a corded drill, lubed the hole with 3-in-1 oil and drilled slowly but methodically holding the drill as perpendicular to the barrel as humanly possible!) I had used my digital micrometer to measured the opening size, so I knew where I was starting (0.0835"). When I finished, I was at 0.0945"... I took the rifle to the range, opened up my adjustable gas block to WIDE OPEN and shot a couple rounds. The rifle cycled...YAY! Closed the AGB down to the factory spec (Superlative Arms AGB. 18 turns from closed). Shot the rifle again. Rifle cycled pretty much perfect, but really close to the 3:00 position, so I opened up 1 click...shot again. 3:15'ish. 1 more click (20 turns total now). Shot again...3:20'ish. Good enough for me!
  5. There are tons of "options" when it comes to springs, but as @shooterrex stated, it's really a matter of mass (buffer & spring) vs. gas. For example, my build (using Aero Precision upper/lower/BCG/18" barrel with rifle-length gas tube, Superlative Arms Adjustable Gas Block and carbine length buffer tube) required me to do some tuning because the gas port on the barrel was NOT drilled to proper specifications. After asking for help/guidance here (thank God for the knowledge-base on this forum), I ended up having to purchase a stock Armalite Spring and 5.3oz heavy buffer to verify my rifle cycled properly. It did not. Gas port was too small. Had to drill out gas port. blah blah blah and eventually I got the rifle running like a dream! Long story short, every large frame AR has its' own character and once you identify the proper mass vs. gas proportions, where your rifle will cycle correctly and eject casings at 3:00 -> 4:15'ish, you will love the large frame AR platform (in my opinion). One other thing to note: the large frame AR's prefer to be shot WET (meaning well lubricated), whereas the AR15/M4 platform isn't as persnickety! I'm sure the heavy-hitters with WAY more knowledge than I have will respond. Good luck!
  6. Well done! Looks along the same lines as the Cerakote camo job done on my LR308. ;)
  7. None of my business, but why are you shooting steel cased ammo? (just a personal curiosity; every type of steel cased ammo has been nothing short of $h!t for M4/LR308 for me). Now, for a thought to help (maybe): Do you have a digital caliper? If so: 1) Measure the case width of the steel ammo, record the measurement 2) Measure the head width of the steel ammo, record the measurement 3) Measure the case width of the brass ammo, record the measurement 4) Measure the head width of the head ammo, record the measurement With the information above, you might be able to ascertain why the steel ammo is working properly and the brass ammo IS NOT. Best of luck.
  8. Best of luck! I had issues after the build of my LR308; had to drill the gas port to fix...but in the process, I removed my JP SCS and got a stock Armalite spring and 5.3oz buffer to ensure 'standard' parts blah blah blah. Once I got the gas side squared away (drilled out, open up gas block wide open, confirmed proper cycling, adjust gas block down for proper timing, then re-install the JP SCS and verify cycling is still proper (it was) and voila). Will keep the stock spring & buffer for any other LR308/AR10 builds I do.
  9. Standard spring with 5.3oz buffer, open gas block WIDE OPEN to start, then dial in after issue is resolved.
  10. If you are running an adjustable gas block, remember to open it up WIDE OPEN for the first round of shooting. Also remember to run the gun wet...so as to allow proper seating/wearing in. :) Aero Atlas R-One or S-One are high-profile, if that helps.
  11. Great Guns? Have not heard of that range; just looked that up. It's a ways north, but is also NOT out in "boonieville USA" like Pawnee (lol) and is about 45 minutes less driving (one-way) for me. That range looks like it could well be a good place to spend some time; is it very busy? Thanks for the heads up @FOGeologist!!!
  12. I zero for 200yds, as it is easier to do the math for further out (for me). For the .308 round, most ballistics charts I have looked at show the .308 round traveling flat to out 50yds, then a slight rise, then back across zero at 200yds as the bullet drop starts for real. So, for your question, I'd go with whatever scope zeroing process you have used in the past, as the muscle memory will be better overall. You can adjust better with what is familiar, rather than trying to learn a new distance for zeroing / problem identification, etc. I had intentions to go out to Pawnee Sportsman's Center this summer to use their long-distance range, to really dial in my rifle for distance...alas, life happened in a myriad of ways. (sad panda)
  13. Please give details on what components you have used, so that the brainiacs here can provide quality and accurate suggestions / advice.
  14. Yeah...precisely. I've got a lot of absolutely USELESS data like that in the various nooks & crannies in my noggin. Purging efforts have been fruitless.
  15. Could be worse; could be phone numbers AND addresses spanning back to the mid-to-late 60's (my brain really hurts! )
  16. Have you measured your gas port diameter with a digital caliper? If it is between .090 and .095 (based on what @98Z5V stated for my build, which is quite similar), then you're okay. IF NOT, then drill baby drill! (FWIW: My gas port diameter, measured with digital caliper, was .0835 from factory; rifle would not cycle normally. After much adoo, I drilled it out to .0945 and the rifle runs flawlessly!!!)
  17. Glad your rifle is up n runnin too! I used a toothpick to measure the distance from top of barrel outside to bottom inside of barrel, then split the distance in half and taped the drill bit at that distance (enough tape to prevent the bit from going in any deeper). Worked like a charm. :P
  18. Range Update (08/07/2022): Took the rifle to the range today (son wanted to go shoot his custom M4). Here's the details... 147gr --> Ejection at 3:20 150gr --> Ejection at 3:20 180gr --> Ejection at 3:30 On a whim, I decided to swap back to my JP Rifles SCS (buffer weight 5.6oz (2 steel, 1 tungsten) measured on digital scale). Shot all three round grains again; same ejection position. All in all, I am very content with how my rifle is working now. Again, thanks to ALL for the support, guidance, advice and banter. :)
  19. After looking at the video, I realized two things: 1) bipod was not perpendicular to the rifle and 2) as you stated, I was not pre-loading the bipod. Sloppy to say the least, but my main focus was really the cycling of the rifle. I will, however, incorporate that into my pre-shot routine, so that muscle-memory comes into play in short order! (love even more sage advice! :P)
  20. Yes it does (and you gotta be bored to watch that! LMAO); now I can fine-tune, get the scope sighted in for 200 yds and enjoy the new tool. This build as been an incredible learning experience, even with all of the stupid $hit that comes with first builds!
  21. In case anyone is REALLY (REALLY) bored, here is the video I shot, to check the ejection location:
  22. Thanks! Advice was the biggest part. The fact that I have researched a dozen barrel Mfr's and all of them are making their gas port TOO SMALL (comparing 18" barrels, since that is what I am familiar with given my situation and experience). I am grateful for all the sage wisdom, discussion and banter too!
  23. WE HAVE PROPER CYCLING!!!!!! Started with AGB wide open; after first 2 rounds to verify cycling, I closed AGB down to factory 'starting' position (18 clicks for Superlative Arms AGB) and shot 12 rounds! Ejection at 3:30 position (I shot video to verify ejection position) ! WAAAAAHHHHOOOOO
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