New AR build will not cycle open
- Thread starter Helka
- Start date
Got out to the range with the BAD lever removed. Go figure that my 223 brass with 20.8 grain had no FTF. But on the last bullet it would only power the bolt 3/4. But my regular 22.3gr locked it back no issues. Problem fixed. May still look at a lighter buffer tho.
Thanks again to all that helped solve this problem.
Thanks again to all that helped solve this problem.
I'm ashamed at myself that I didn't ask what ammo you were running right off the bat.........
.......we could have saved a lot of time lol
9 times out of then when someone's new AR15 isn't working and they're running reloads.........the gun isn't the problem
That makes two of us! How’d we all miss that one.
What's a 3/4 stop?
Are you saying it's catching on the carrier and not on the bolt face?
Since this is a build, what LPK did you use? Maybe it's not locking back because of a bad catch not the gas system. Does the bolt catch moove freely? Strong spring? When activated does it move up far enough to catch the bolt or is it just catching the lower edge?
Strange that it still short strokes occasionally. With the gas block adjuster wide open and a low mass carrier you should be overgassed.
Have you tried other magazines? Same ones that work well in your S&W?
Try swapping in the bolt carrier from your S&W and see if it helps or makes it worse. Also try the low mass carrier in the S&W and see how it shoots.
Have you tried sticking drill bits into the gas port yet (to measure the port size)? Is the port wide open into the bore with no crud in there? Same with the gas block, it there any way to see if there is an obstruction? Blow air backwards through it or remove the adjuster screw and inspect it and the port?
Just trying to see if we can narrow down what is causing the issues.
Have you read the AR lubrication sticky yet?
Improper lubrication can cause issues as well, too much and too little. People like to say an AR needs to run wet. This is false, it needs to be lubricated properly not just loaded up to where it's oozing out all over the place like I've seen some guys do.
Note to every member, the Magpul BAD lever is the worst thing they've ever made and has caused nothing but problems for many people. If you like what the BAD lever does but want something reliable look at the Phase5 EBR. It's a much better option.
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A light loading like that with a rifle lenght gas system is going to cause you to be under gassed. Not enough propellant to make the rifle cycle properly. Try upping the powder charge. Changing everything out wont be as easy as just adding a grain of powder. An adjustable gas block doesnt magically give you more gas. You could also find someone to open up your gas port if you are dead set on running that light load.
I don’t plan on running that low I was just following the Hornady recipe for the starting load. I do the regular 3 bullets at each interval and which ever has the best grouping then hone that load with .3 grain increments.
Hornady tends to lawyer up their load data pretty heavily. I always start in the middle of the min and max and usually end up going 2 or 3 gr past max. What weight of bullets are you using?
I’m running 22.1 grns of H335 under 55gr bullets and it cycles fine in my 18” Rifle length gas, carbine buffer and tube...Soft recoil but never any issues. I’m also running a standard non-adjustable gas block though too, but i’d say up your charge slightly and you shouldn’t have any problems.
Interesting thread.
I just finished my first "FU C-71" build.
16" barrel with a carbine length gas system.
Was thinking about getting an H1 but may try the Carbine standard buffer first.....if Silverdale reopens some time soon.
My load is the 55 Campro over 24.2 grains of 3031
I just finished my first "FU C-71" build.
16" barrel with a carbine length gas system.
Was thinking about getting an H1 but may try the Carbine standard buffer first.....if Silverdale reopens some time soon.
My load is the 55 Campro over 24.2 grains of 3031
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The problem is under gassing due to low powder charge in the ammo. I use 55g hornady projectiles with 24g of h335 and sometimes I find it difficult to cycle compared to factory. 24g is a fairly light load so I can't imagine how less than that would cycle reliably.
