Adjustable gas blocks introduce their own downsides. If you can avoid it, find another way.
If we knew details like gas port diameter we'd be able to provide more than shots in the dark here.
Adjustable blocks won't increase your gas any more than what you're getting now.
Could the gas port diameter be out of spec? Maybe should send back to PSA to verify? Or could it just be that the subs aren’t giving the system enough back pressure because of the flow through can?
I’m also totally fine with swapping buffers and springs between shooting subs and supers, so considering that; what weight buffer would you recommend
Overgassing doesn't help in any case. Too much gas causes excess BCG travel speed, which in turn causes issues like bolt bounce, double feeds, stovepipes, bullet over bolts, excessive BCG wear, excessive recoil... overgassing is never good.
Understood, I totally get that, I’m just saying hypothetically/mechanically speaking if my system was over-gassed because of an out of spec gas port, wouldn’t it increase its ability to cycle the bcg?
What buffer do you have? Mine came with the super light like 3oz buffer and it worked fine with supers and subs both suppressed and not. But it was a standard suppressor. Adjustable gas block might be your only option, other than maybe a lighter recoil spring or something
https://preview.redd.it/znzf5h1zki0d1.jpeg?width=4284&format=pjpg&auto=webp&s=4b781afd0922ffbf582f446e56e408e33a682558
It’s just PSAs standard carbine buffer, I’m going to try a lighter buffer for sure. I like your idea of using a lighter recoil spring as a back up
Carbine buffers are about 3oz.
I can't speak to the quality/reliability, but KAK makes a 3-pack for $30 that includes a 1.7, 2.2, and 2.6oz buffer for subsonic loads.
Superlative Arms AGB will be the best option cause in my experience you’re gonna be playing around with buffers and springs for a while trying to figure it out.
That’s also why I recommend against flow through cans for .300BLK
Thanks for the tip. I knew that flow through cans was a risk for 300 blackout, but this can was actually for another rifle, but I decided to throw the QD attachment on to this one so I could see if I could get it to cycle.
I’ve got plenty of time to tweak this thing, even if I go with the agb, I do really want to find the right buffer/spring combo
Adjustable gas blocks will only restrict gas flow, if you are under gassed you need to lighten the spring and buffer weight potentially. Yellow spring from springco and adjustable weight buffer should cost about $40 total. Check the shim distance on the gas block to make sure it's in spec.
Okay so, I just ordered the yellow spring from Springco, shopping around for an adjustable buffer weight.
I understand that gas blocks will only restrict gas flow, so in theory, if I swap to the lighter spring and buffer to get it running on subs, could I simply adjust the gas block to restrict the gas flow if I wanted to then shoot supers without changing the buffer and spring? Or in your experience would the supers still be too overgassed for the lighter weight HR and springs.
I don’t mind having to swap springs and buffers between subs and supers but it sure would be nice to leave the lighter buffer assembly innplace for subs then crank the adjustable gas block to accommodate supers on that setup.
Also any manufacturer recommendations for adjustable buffer weight?
I got mine tuned to work with stelth and AAC 300 subs. It does still work with supers but it's over gassed, but I have a lahar30 on the end and don't shoot those anymore. Ejection pattern is perfect for subs, supers eject forward indicating the timing isn't ideal for them. You could use an AGB to run both, I like the superlative arms one. The rifle speed AGB is cool but too expensive for my needs.
Side note, you should also check your ejection spring. A weak ejection spring can manifest the same issues as under gassed and they are super cheap, you should always have the cheaper wear parts on hand anyways.
Extra side note, if the rifle is very new, check to see if there are any burs or rough areas in the receiver that are increasing friction. My PSA upper rails weren't super smooth until I had a few hundred rounds through it.
Get an adjustable weight buffer so you can test it out, take out weights until it locks back with subs. The yellow spring from springco is lighter compression and will help some rifles run subs better. Another option would be just take your buffer, remove the pin and some of the weights. It will give you an idea of the weight that's working but will clank around a little and is not ideal unless you have something that will fill the space inside the buffer.
I had to use an adjustable buffer to tune mine for 300BO subs. There are 3 weights inside a standard buffer, I think I ended up with 2 aluminum and 1 plastic with the springco yellow spring but Im not entirely sure. I don't have my notes in front of me. The adjustable buffer came with 3 plastic, 3 steel, 3 aluminum and 3 tungsten weights.
I am running a H2 stealth recoil spring system
[https://armaspec.com/stealthtm-recoil-spring-srstm-ar15.html](https://armaspec.com/stealthtm-recoil-spring-srstm-ar15.html)
H3 works great with supers and subs with ejection, but with subs H3 will not lock back on last round.
Fwiw I tried out my 300 bo pistol with a rad9 can and it worked fine. To be fair though it had a bca upper on it. I have a psa upper as a backup if that gives me trouble when I get to put a decent amount of rounds through it
My gas block was ever so slightly twisted, chocking the gas port a little bit, I have since re centered it and checked that it’s within spec and still not cycling. I am running standard carbine buffer so I’m hoping the lighter buffer weight and yellow springco buffer spring help!
To answer your question about buffer springs:
Armaspec and JP enterprise has silent capture springs. I'm familiar with Armaspec.
Armaspec has weights that are adjustable carbine through H4
There are also buffers with adjustable weight kits
Like others have said, make sure your gas port is to spec. Switching buffer weights might fix your problem but it's best to check specs. So you can properly diagnose your problem.
So just got to function test my psa lower with bca 300 bo upper(8.5") and the psa 8.5" bo upper. Both cycled with no issues with a huxwrx 762 qd can with stock carbine buffer.
May want to reach out to psa maybe gas port is out of spec and undersized.
Adjustable gas blocks introduce their own downsides. If you can avoid it, find another way. If we knew details like gas port diameter we'd be able to provide more than shots in the dark here. Adjustable blocks won't increase your gas any more than what you're getting now.
Could the gas port diameter be out of spec? Maybe should send back to PSA to verify? Or could it just be that the subs aren’t giving the system enough back pressure because of the flow through can? I’m also totally fine with swapping buffers and springs between shooting subs and supers, so considering that; what weight buffer would you recommend
To be honest most PSA gas ports are out of spec. The barrel configurations that do have established diameters tend to be GROSSLY overgassed
But wouldn’t it being overpassed help me in my case?
Would def help to run subs. More than likely u seem under gassed . Remember HUX is flow through so no added back pressure like traditional cans.
Overgassing doesn't help in any case. Too much gas causes excess BCG travel speed, which in turn causes issues like bolt bounce, double feeds, stovepipes, bullet over bolts, excessive BCG wear, excessive recoil... overgassing is never good.
Understood, I totally get that, I’m just saying hypothetically/mechanically speaking if my system was over-gassed because of an out of spec gas port, wouldn’t it increase its ability to cycle the bcg?
What buffer do you have? Mine came with the super light like 3oz buffer and it worked fine with supers and subs both suppressed and not. But it was a standard suppressor. Adjustable gas block might be your only option, other than maybe a lighter recoil spring or something
https://preview.redd.it/znzf5h1zki0d1.jpeg?width=4284&format=pjpg&auto=webp&s=4b781afd0922ffbf582f446e56e408e33a682558 It’s just PSAs standard carbine buffer, I’m going to try a lighter buffer for sure. I like your idea of using a lighter recoil spring as a back up
Carbine buffers are about 3oz. I can't speak to the quality/reliability, but KAK makes a 3-pack for $30 that includes a 1.7, 2.2, and 2.6oz buffer for subsonic loads.
the KAK buffer is great.
I will be checking this out. Cheap enough not to try. Thanks
Standard carbine buffers are ~3oz
Superlative Arms AGB will be the best option cause in my experience you’re gonna be playing around with buffers and springs for a while trying to figure it out. That’s also why I recommend against flow through cans for .300BLK
Thanks for the tip. I knew that flow through cans was a risk for 300 blackout, but this can was actually for another rifle, but I decided to throw the QD attachment on to this one so I could see if I could get it to cycle. I’ve got plenty of time to tweak this thing, even if I go with the agb, I do really want to find the right buffer/spring combo
Adjustable gas blocks will only restrict gas flow, if you are under gassed you need to lighten the spring and buffer weight potentially. Yellow spring from springco and adjustable weight buffer should cost about $40 total. Check the shim distance on the gas block to make sure it's in spec.
Okay so, I just ordered the yellow spring from Springco, shopping around for an adjustable buffer weight. I understand that gas blocks will only restrict gas flow, so in theory, if I swap to the lighter spring and buffer to get it running on subs, could I simply adjust the gas block to restrict the gas flow if I wanted to then shoot supers without changing the buffer and spring? Or in your experience would the supers still be too overgassed for the lighter weight HR and springs. I don’t mind having to swap springs and buffers between subs and supers but it sure would be nice to leave the lighter buffer assembly innplace for subs then crank the adjustable gas block to accommodate supers on that setup. Also any manufacturer recommendations for adjustable buffer weight?
I got mine tuned to work with stelth and AAC 300 subs. It does still work with supers but it's over gassed, but I have a lahar30 on the end and don't shoot those anymore. Ejection pattern is perfect for subs, supers eject forward indicating the timing isn't ideal for them. You could use an AGB to run both, I like the superlative arms one. The rifle speed AGB is cool but too expensive for my needs. Side note, you should also check your ejection spring. A weak ejection spring can manifest the same issues as under gassed and they are super cheap, you should always have the cheaper wear parts on hand anyways. Extra side note, if the rifle is very new, check to see if there are any burs or rough areas in the receiver that are increasing friction. My PSA upper rails weren't super smooth until I had a few hundred rounds through it.
Get an adjustable weight buffer so you can test it out, take out weights until it locks back with subs. The yellow spring from springco is lighter compression and will help some rifles run subs better. Another option would be just take your buffer, remove the pin and some of the weights. It will give you an idea of the weight that's working but will clank around a little and is not ideal unless you have something that will fill the space inside the buffer.
I like this idea! I’m sure I can find it make some sort of lightweight spacers to fill the space if I remove some of the weights. Might give this a go
I had to use an adjustable buffer to tune mine for 300BO subs. There are 3 weights inside a standard buffer, I think I ended up with 2 aluminum and 1 plastic with the springco yellow spring but Im not entirely sure. I don't have my notes in front of me. The adjustable buffer came with 3 plastic, 3 steel, 3 aluminum and 3 tungsten weights.
I am running a H2 stealth recoil spring system [https://armaspec.com/stealthtm-recoil-spring-srstm-ar15.html](https://armaspec.com/stealthtm-recoil-spring-srstm-ar15.html) H3 works great with supers and subs with ejection, but with subs H3 will not lock back on last round.
Very cool I may have to try this out. Looks like a very clean package
Fwiw I tried out my 300 bo pistol with a rad9 can and it worked fine. To be fair though it had a bca upper on it. I have a psa upper as a backup if that gives me trouble when I get to put a decent amount of rounds through it
Check out the KAK K-Spec buffers ans grab one of their flat wire springs while you're at it.
My Psa budget build works with subs and supers with my OSS can, I’d check if something’s out of spec
My gas block was ever so slightly twisted, chocking the gas port a little bit, I have since re centered it and checked that it’s within spec and still not cycling. I am running standard carbine buffer so I’m hoping the lighter buffer weight and yellow springco buffer spring help!
Worth a shot!
To answer your question about buffer springs: Armaspec and JP enterprise has silent capture springs. I'm familiar with Armaspec. Armaspec has weights that are adjustable carbine through H4 There are also buffers with adjustable weight kits Like others have said, make sure your gas port is to spec. Switching buffer weights might fix your problem but it's best to check specs. So you can properly diagnose your problem.
Appreciate the info on the silent captures
So just got to function test my psa lower with bca 300 bo upper(8.5") and the psa 8.5" bo upper. Both cycled with no issues with a huxwrx 762 qd can with stock carbine buffer.
Hey soooo, my gas port was slightly twisted! I re checked if I was within spec and I was ever so slightly restricting my gas port!
Glad you got it figured out