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About panel77

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  1. so with the Broken arms lower and the BCA complete, untouched upper as unboxed, its had 100+30+30+30 with all PMAGs but a pile of them-all different. zero issues. None. (1 round issue but that was a round issue not a gun issue-steel cheapo ammo) all ammo was steel cheap tula/wolf 100% function. I didnt even change the gas tube to mate into the middle of the cutout as instructed by 98 All the lower parts came directly from the other non-working AMT lower-buffer, spring, tube...., LPK so to conclude, either the BCA has a lower center allowing it to 'grab' rounds easier OR the Broken Arms lower puts its mag catch higher by 0.02x to put the rnd in the right place. I kinda doubt the BCA upper is the change... and its because i used a different upper with the PSA upper assembly installed on a AMT upper with the Broken Arms lower and it functioned fine, sorta... with my "buddy" drilling out the gas port to 96, now it suffers from other issues relating to massive over-gassing. It never suffered from failing to grab a rnd but it ejected 1 rnd so hard it flipped and tried to load the empty shell in line but backwards....(no pic) So the centerline of the AMT upper with PSA parts worked fine and will work perfect once i get an adjustable gas block on there and crank it back down to where it should have been in the 76-80 port hole size range. This leads to a conclusion that the mag catch sitting too low in the lower makes the rifle not function. I already took one of the lowers and threw it on the mill and slotted the catch out to allow it to sit higher. I havnt dragged my welder home from other buddys house to add onto a mag catch and install yet but i think it will be the solve for these 2 AMT lowers that have the mag catch slot in the wrong spot-too low. AMT when contacted when i pressed(multiple phone calls) them to change the spec, they finally revealed they do not make the lowers(and prob not uppers) and would pass along my info to maker. They did give me credit and were above and beyond. I still would not buy any lower from any company without making sure that mag catch is in the 0.65-0.67 range from the top to the top of the mag catch slot. I would have really preferred 0.65 from Broken Arms and others were in that closer range but his customer service was such I had to buy from him. The fit was average to the AMT upper. The AMT upper and lower fit together VERY well, flat and no gap and very very thin parting line-but the mag catch slot location is a fail. I would buy from a company that has 0.65 AND has their own matching upper. Buy as a package deal and dont be cheap.(it always costs more to get right)
  2. Good points. Tolerance stacking is certainly an issue. The 80% machining process can not change really any reasonable spec other than trigger placement as thats the only thing you are machining. The placement of mag catch and other items such as upper attachment holes and buffer tube placement are already set. using the same makers upper and matched 80% lower gave the same result finally leading to the measurement poll where with over 15 makers represented, it appears this single maker has a tolerance issue. It will function. barely, and not all the time. measurement taken from top of mag catch to top of lower. using a lower within the closer range of spec(0.65-0.70) as opposed to the 0.685+ of the defective lower appears to have totally solved the problem irregardless of any other issue such as gas port, tube length, buffer size/weight, buffer spring length... tube size etc....
  3. 50 cents worth of advice.... worth a lot more than that!! 😃
  4. Thanks-i got on the email list the day you sent link.
  5. Out of stock-almost permanently. what about this? no specs/length given and it has the short buffer. https://kmtactical.net/308-mil-spec-carbine-buffer-tube-assembly.html
  6. yep-dinged the ears a TINY bit. looks like maybe less than 1/16" of damage, probably less. basically nicked 1 thread about halfway in the the sharp edge of the thread on each side. dropped 2 quarters in and its exactly 7 5/8. havnt shot again.
  7. Ears? please define. I used google images, couldnt get a clear idea. i pulled upper off lower and did not see any strike marks in obvious places that the bolt is around.
  8. 55 isnt a bad price for what you are getting. and i try to keep groups together they way supplied from me until something screws up. I agree about PSA-10 i will say the 15 has been flawless. but i think in general i would prefer to NOT support PSA... they were the first cheap option i found and at teh time, i was on an insanely "dont tell teh wife" budget. things are slightly better now but with the combo with bear creek working now-im gonna stick with that and fiddlebump the rest as i get time and money and availability. thank you!
  9. ignore-failure to edit in time for accuracy, it apparently posted a draft.... buffer tube is PSA 7.75 and since nobody anywhere lists lengths on tubes, i will have to crawl back to PSA and wait for in stock and being charged market rate...
  10. broken arm 80% lower mostly CMMG off shelf LPK top of mag slot to top of upper-0.6665 13.5" spring 5.4 buffer (same length as ar15 buffer) 7.75 buffer tube BCA 18" assembled upper with the still too short gas tube. ----- no malfunctions at all with about 100 rounds. - swapped to teh A2 PSA upper with correct length gas tube, upper that matches teh AMT lower, and the gas port drilled to 096... BIG MISTAKE. shoulda taken pictures. if the spent shell casing was tapered at both ends, it would have PERFECTLY loaded itself. 180' flip so open mouth facing bolt. more than 1 time. gotta put an adjustable gas block on that one now. im SURE the opened up too much port is the problem. BUT.... the BCA assembled, out of the box upper with too short gas tube and unknown port size performed EXACTLY like it should and how i EXPECT it should have in teh first place. the AMT lower with 0.95x space between mag catch and upper was WRONG compared to this 0.66x and I am FULLY convinced that the lower is the problem. BUT.... that being said, every single lower will get the exact same specs-same buffer, tube, spring
  11. so i failed to edit this properly before it posted-IGNORE the buffer tube length-it was measured WRONG. IGNORE THAT NUMBER
  12. broken arm 80% lower mostly CMMG off shelf LPK top of mag slot to top of upper-0.6665 buffer tube 7.00" spring 13.5" buffer 5.4 oz, BCA 18" assembled upper with teh still too short gas tube. 10 minute range day tuesday
  13. 20. not measurably a lot but im grasping at straws... still havnt made the time (and ammo money) to take a banquet table out, stip everything to nuts, measure it all and break out the yellow pad and start trying to make a fail. the stinker is that i cant have a fail even now cause it will make me think that when it counts(charging hog) i will have a gash instead of a bang. unwieldy hammer... and i have yet to see a hatchet as an MLOK attachment. the PSA 223/80% has never, ever failed. steelcase, brass, really poor handling skills...
  14. What about the new centerline for the mag button? wont that cant the screw downwards and create drag/resistance?
  15. yep-top of lower to top of mag catch-right in the range of others.-straight from teh maker. got another lower-going to take teh guts out of one of the matched pairs and use it in teh new lower. mess around with identical parts and see if the lower is the fail-if it is, then just going to take teh 2 defective lowers, machine the slot closer to the upper, then weld 2 mag catch pieces together, machine off to match the correct height and adjust teh actual catch part to teh correct height and make them proprietary catch for those very specific lowers allowing me to run any upper and any mag without thinking.
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