06-23-2018, 02:55 PM
I preface the following with the fact that I experienced your same failures on my first build, and after finding this forum and reading a while have learned the following. I am no expert.
Where is your ejection pattern developing when you have successful ejections? It should be 330-4 o'clock.
Are you getting claw marks in the extractor groove of your cases? Have you tried rounding the face of your ejector, polishing the extractor claw, etc...? https://www.youtube.com/watch?v=kMrMUyyWV0k
Are you reloading the brass with which you had no issues, or are you using a different brand?
Do you know what your gas port size is?
I assume you started with your gas block wide open, and fired groups of rounds until failure at each adjustment going downward to 1/2 closed? I have always used the "from closed" method in setting my AGBs, which I find works better than going the other way. You want enough gas to operate your system without failure, any more (there is a window) and it starts to get spastic and harder to diagnose. There are a lot of variables involved here, gas port size, gas system length, gas block alignment, gas system seal, friction of the carrier in the receiver, spring tension, buffer weight, load, projectile, etc. You want to find the window your rifle functions well in after accounting for the many possible variables. The only real way to do that is to fire lots of rounds, from all your potential sources of ammunition, and ensure that the system is properly built.
Building with high quality components is the surest way to guarantee a big "window" with which to operate your system, allowing a greater range of variance in these variables without having to determine adjustments. The bigger the window, the more likely you are to have an all round well running rifle.
I have only used AGBs from ODIN, SLR, and on my Anderson Arms piston carbine. My process is to close the block down, fire to ensure no gas operation at all, then open a single turn. Then, loading 10 rounds, I fire and observe the ejection pattern until I get a failure. I then open another full turn, and repeat. At this point I'm usually able to find rather quickly a spot at which my rifle functions well, with ejection about the 330 position, and I will usually add another 1/3-1/2 turn. I will then switch to Wolf steel, and fire until failure, which so far has never been an issue. 1/40 rounds is my minimum standard in Grendel.
I put a lot of the info together after watching Johnny's video above. Hope this helps.
Where is your ejection pattern developing when you have successful ejections? It should be 330-4 o'clock.
Are you getting claw marks in the extractor groove of your cases? Have you tried rounding the face of your ejector, polishing the extractor claw, etc...? https://www.youtube.com/watch?v=kMrMUyyWV0k
Are you reloading the brass with which you had no issues, or are you using a different brand?
Do you know what your gas port size is?
I assume you started with your gas block wide open, and fired groups of rounds until failure at each adjustment going downward to 1/2 closed? I have always used the "from closed" method in setting my AGBs, which I find works better than going the other way. You want enough gas to operate your system without failure, any more (there is a window) and it starts to get spastic and harder to diagnose. There are a lot of variables involved here, gas port size, gas system length, gas block alignment, gas system seal, friction of the carrier in the receiver, spring tension, buffer weight, load, projectile, etc. You want to find the window your rifle functions well in after accounting for the many possible variables. The only real way to do that is to fire lots of rounds, from all your potential sources of ammunition, and ensure that the system is properly built.
Building with high quality components is the surest way to guarantee a big "window" with which to operate your system, allowing a greater range of variance in these variables without having to determine adjustments. The bigger the window, the more likely you are to have an all round well running rifle.
I have only used AGBs from ODIN, SLR, and on my Anderson Arms piston carbine. My process is to close the block down, fire to ensure no gas operation at all, then open a single turn. Then, loading 10 rounds, I fire and observe the ejection pattern until I get a failure. I then open another full turn, and repeat. At this point I'm usually able to find rather quickly a spot at which my rifle functions well, with ejection about the 330 position, and I will usually add another 1/3-1/2 turn. I will then switch to Wolf steel, and fire until failure, which so far has never been an issue. 1/40 rounds is my minimum standard in Grendel.
I put a lot of the info together after watching Johnny's video above. Hope this helps.
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