User Panel
[Last Edit: dHUTCH]
[#1]
Originally Posted By GriswoldGuns:
I just assembled my upper using the Stealth 20" that I won. Used a Magpul BEV block to mount barrel nut to 50ft pounds and A2 flash hider. Looking from muzzle, gas block looks slightly canted clockwise. Did I somehow loosen barrel extension? Or is there a chance that gas port/dimples are off a couple degrees? I am freaking out. View Quote Did you over torque at some point and start to shear the index pin on the barrel extension? |
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Official Arfcom Nickname: 3 Gun
Whack-a-mole Champ |
[Last Edit: GriswoldGuns]
[#2]
Originally Posted By dHUTCH:
Did you over torque at some point and start to shear the index pin on the barrel extension? View Quote View All Quotes View All Quotes Originally Posted By dHUTCH:
Originally Posted By GriswoldGuns:
I just assembled my upper using the Stealth 20" that I won. Used a Magpul BEV block to mount barrel nut to 50ft pounds and A2 flash hider. Looking from muzzle, gas block looks slightly canted clockwise. Did I somehow loosen barrel extension? Or is there a chance that gas port/dimples are off a couple degrees? I am freaking out. Did you over torque at some point and start to shear the index pin on the barrel extension? I didn't use a torque wrench for muzzle device as it was an A2. 12 o'clock port was at 6 o'clock when finger tight. 1/2 turn and stopped, crush washer looks like it could crush a little more. Eta: flash hider was put on using a 8" long cresent wrench and 1 arm. Barrel nut was torqued to 45 ftlbs then backed off and re torqued to 50. Aero M4E1 upper. |
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[#3]
It happens some times when drilling the port and dimples.. I had a stealth barrel that had a canted gas block. Mine was canted enough that the block could touch the inside of the rail. If it's a small amount and it's not touching the rail and the gas tube is not binding in the bolt carrier you should be fine. If it is a issue or bugs you just call Larue and they will take care of you.
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[#4]
M4E1 upper?
My money is on the upper pin slot is out of spec. |
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[#5]
Originally Posted By STEVE717:
It happens some times when drilling the port and dimples.. I had a stealth barrel that had a canted gas block. Mine was canted enough that the block could touch the inside of the rail. If it's a small amount and it's not touching the rail and the gas tube is not binding in the bolt carrier you should be fine. If it is a issue or bugs you just call Larue and they will take care of you. View Quote You just lifted my spirits. It's maybe 5° canted and gas tube isn't binding. Its hidden under rail, so as long as it is safe to shoot, I am not worried. |
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[#6]
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[#7]
Originally Posted By dHUTCH:
Did you over torque at some point and start to shear the index pin on the barrel extension? View Quote View All Quotes View All Quotes Originally Posted By dHUTCH:
Originally Posted By GriswoldGuns:
I just assembled my upper using the Stealth 20" that I won. Used a Magpul BEV block to mount barrel nut to 50ft pounds and A2 flash hider. Looking from muzzle, gas block looks slightly canted clockwise. Did I somehow loosen barrel extension? Or is there a chance that gas port/dimples are off a couple degrees? I am freaking out. Did you over torque at some point and start to shear the index pin on the barrel extension? |
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I have been asked to point out that I am LaRue Tactical's owner.
My work has been used by tens of thousands of US Military personnel, and tens of thousands of civilian shooters - ML |
[#8]
Originally Posted By GriswoldGuns:
You just lifted my spirits. It's maybe 5° canted and gas tube isn't binding. Its hidden under rail, so as long as it is safe to shoot, I am not worried. View Quote View All Quotes View All Quotes Originally Posted By GriswoldGuns:
Originally Posted By STEVE717:
It happens some times when drilling the port and dimples.. I had a stealth barrel that had a canted gas block. Mine was canted enough that the block could touch the inside of the rail. If it's a small amount and it's not touching the rail and the gas tube is not binding in the bolt carrier you should be fine. If it is a issue or bugs you just call Larue and they will take care of you. You just lifted my spirits. It's maybe 5° canted and gas tube isn't binding. Its hidden under rail, so as long as it is safe to shoot, I am not worried. 5% canted and the gas tube is in center alignment with the upper's gas tube slot? Something's not adding up. How is the gas blocks alignment relative to the barrel extension's pin, are they aligned? |
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Back the Blue.
1,000,000 view! Alcohol and Calculus Don't Mix, Never Drink and Derive. Certified LaRue Armorer |
[#9]
Originally Posted By Defender3:
5% canted and the gas tube is in center alignment with the upper's gas tube slot? Something's not adding up. How is the gas blocks alignment relative to the barrel extension's pin, are they aligned? View Quote View All Quotes View All Quotes Originally Posted By Defender3:
Originally Posted By GriswoldGuns:
Originally Posted By STEVE717:
It happens some times when drilling the port and dimples.. I had a stealth barrel that had a canted gas block. Mine was canted enough that the block could touch the inside of the rail. If it's a small amount and it's not touching the rail and the gas tube is not binding in the bolt carrier you should be fine. If it is a issue or bugs you just call Larue and they will take care of you. You just lifted my spirits. It's maybe 5° canted and gas tube isn't binding. Its hidden under rail, so as long as it is safe to shoot, I am not worried. 5% canted and the gas tube is in center alignment with the upper's gas tube slot? Something's not adding up. How is the gas blocks alignment relative to the barrel extension's pin, are they aligned? Maybe 3° of cant. Upper has a long hole for gas tube, and tube is rifle length. Don't have means to tear it apart tonight, and would like to avoid that if I can. |
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[#10]
Originally Posted By GriswoldGuns:
That won't affect function, will it? Bolt locks in freely and feeds fine by hand. View Quote View All Quotes View All Quotes Originally Posted By GriswoldGuns:
Originally Posted By jeep450:
M4E1 upper? My money is on the upper pin slot is out of spec. That won't affect function, will it? Bolt locks in freely and feeds fine by hand. I built a M5E1 and the pin slot was too big. I had issues getting the barrel nut tight and keeping the barrel straight. It shouldn't effect anything. |
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[#11]
Originally Posted By jeep450:
I built a M5E1 and the pin slot was too big. I had issues getting the barrel nut tight and keeping the barrel straight. It shouldn't effect anything. View Quote View All Quotes View All Quotes Originally Posted By jeep450:
Originally Posted By GriswoldGuns:
Originally Posted By jeep450:
M4E1 upper? My money is on the upper pin slot is out of spec. That won't affect function, will it? Bolt locks in freely and feeds fine by hand. I built a M5E1 and the pin slot was too big. I had issues getting the barrel nut tight and keeping the barrel straight. It shouldn't effect anything. I am guessing it must be my upper, or a slightly off jig at Larue, both of which are so minor that I think I should be okay to shoot it. I don't think I could have applied enough torque to shear the index pin without hurting my hand with the tools I was using for muzzle device. |
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[#12]
You could loosen the barrel nut a little and try to turn the barrel. I'd bet that the slot is a little wide.
If it turns that's what it is, put a strap wrench on the barrel and turn counter clock wise while tightening the barrel nut down. |
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[#13]
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[#14]
Photos go a long way for some of us
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[Last Edit: GriswoldGuns]
[#15]
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[#16]
Look at your feed ramps in the upper and see how they line up with the upper ramps.
If they don't lineup either the pin sheared or the slot is too large allowing the cant. |
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[Last Edit: GriswoldGuns]
[#17]
Feed ramps look good.
So if pin is not sheared, extension is still headspaced properly and it's likely a slightly canted gas port? |
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[#18]
That would be my guess, assuming the gas block is drilled correctly.
I would still loosen the nut and see if the barrel would turn. |
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[#19]
Broke it down, there was a tiny bit (less then a degree of turn in barrel/receiver fit) and the gas block had a little side to side play when I backed the set screws out (glad I used blue loctite instead of red).
Triple checked alignment during reassembly and it looks much better. Thank you all for the suggestions. |
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