This is my first AR, and I think it hits a little hard when it cycles supers. Trolling seems to show most people recommending an H2 buffer. And so this is my first, I have nothing to compare it to. So this is more an opinion, or gut instinct. However, others that have shot it agree, it hits kinda hard…
8.5” barrel, pistol gas system, standard carbine buffer.
Thoughts?
Personally, I would leave it alone if it cycles reliably. If you want to mess with it just to mess with it, at least the buffer is easy to change and undo if it stops cycling.
If you really feel like messing with it, you could get an ODIN Works adjustable buffer. I have one for my BCM 300 black. Easy to change weights, just a matter of how much stuff you can do to your gun at the range if you don’t have other open space you can shoot.
At that length barrel you should have something heavier than a standard carbine.
Fwiw, I use a Spikes T2 in my 8.5 300blk sbr. The T2 is heavier than an H1 and less than an H2. It cycles subs and supers without an issue.
For what it’s worth, with the standard carbine buffer, I can’t run subs. I know that’s somewhat common, but I haven’t done my Form 1 yet and started my suppressor. I’m pretty sure once that’s done, it’ll cycle properly. It just won’t strip the next round.
As for the T2, I appreciate that, hadn’t heard of it. How did you arrive there? Cycling issues with an H2?
I arrived at the T2 because I found someone with my identical barrel and basically copied their gas set up. That was well before adjustable gas blocks.
As for subs, it isn’t supposed to cycle subs without a can unless you are really particular about the gas setup, including port size.
Kind of funny, I think I landed at about that weight with the ODIN Works after a lot of back and forth at the range. Adjust->go to range->shoot->go home->repeat 
My setup uses Vltor A5 buffer tube with the Vitor buffer spring and the Vltor H2 buffer. I don’t run an adjustable gas block. My SBR 300 BO runs reliably with subs and supersonic ammo with or without my suppressor. I run a Fail Zero NIB full auto bolt carrier. The Nickle Boron surface being so slick helps a lot with reliability. I love that I don’t have to use lube on the bolt. Lube attract dust, dirt and carbon. An AR that is properly timed and has the proper weight buffer, bolt carrier and proper buffer spring will run properly. It will also have a softer recoil, slower impulse and a lot less wear and tear than most off the shelf AR. With the additional weight from the buffer and full auto bolt carrier you will get a more thorough burn. You will get less gas blow back.
When my LGS opens this morning I’m going to grab an AP H2 and flat spring as a starting point…
I have all sorts of materials and a lathe at my disposal to play with weights; steel, stainless steel, aluminum, brass, copper, tungsten, delron…if I need some fine tuning.
If one is inclined to experiment with Buffer weighting, there are a few manufacturers making tungsten buffer weights that fit “standard” buffers - Geissele is one that comes to mind.
Odin Works makes an adjustable buffer kit for about $50-$60 or so, complete with weight assortment, and additional weights available. I do not know if their (Odin’s) weights will fit a standard Buffer.
(Tony - I didn’t see you had already addressed Odin Works - I tapped this out quite awhile before I posted; mea culpa)
Adding weight or really mass to the operating system of a SBR that won’t cycle subs or run reliability my seem counterintuitive. If you add too much it will be too heavy to function properly. If you add the right amount of weight then it will delay the impulse just long enough to get a higher chamber pressure. Therefore it should function more reliability with subs. The heavier buffer and bolt will slow the impulse overcoming the extra chamber pressure. Slowing the impulse gives you less felt recoil with less wear and tear. With the heavier bolt and buffer you are storing more energy. With the extra wieght it should also help with stripping the next round out of your mag and feed more reliability.
I know that many of us understand how the direct impingement system on an AR works. This post was for the guys that are new to the AR and that may not understand.
I hadn’t thought of that…and I thought I had a pretty good grasp on the operation…
I’m new to ARs,
The part of the cycle mine won’t complete with subs is picking up the next round and chambering it. It extracts and ejects just fine.
I’m anxious to go shooting again and try this all out. Being so close, I expect it may work.
Thanks
The heavier buffer and bolt carrier has more mass. It takes more chamber pressure to move the greater mass. Therefore it has more kinetic energy. The extra “weight” which really force, exerts more force on your next round over a lighter bolt carrier and buffer.
I’m running H2 buffers in my 9” AAC, 7.5” and 8.5” PSA uppers with no issues. Suppressed or unsuppressed. Supersonic and subsonic.
For years. The 8.5” has even run full auto with no issues when ammo was cheaper (we have select-fire rifles at work)
I’m running an H2 in my 10.5” 5.56 suppressed with no issues either.
Guess what cycled supers AND subs today with just an H buffer?
Supers are still a little harsh, and I’m still going to get an H2…but overall it was a definite improvement.
Sighted in my Romeo and Juliet today as well at 50 yards. I need one of those sandbag things to help steady… I’m certainly no sharp shooter 
Allen I am glad that is all that it was. From what you were describing it sure sounded like that was the problem. I have spent a good while building AR. I have always tried to make them run as smooth as I can. It makes the AR more reliable and less prone to breakages. It will also help with the accuracy. Having an adjustable gas block is ok. To me it is just another thing to fail or to forget to adjust it. It really is better to me to just spend the time to work out the problem with an AR. Where was it throwing your brass and how did the spent brass look? 
Well if any of those targets were man then he would be deader than hell. A little practice to get to know your new best friend and you will be out to three hundred yards still tearing up targets.
No, I really appreciate your help. I’m fairly smart, if I do say do myself
But I never considered adding weight would help a short cycling issue. But once you mentioned it, it was an Ah Ha moment for sure. It all made sense…
Yeah, I screwed up buying an H, that’s on me. Getting excited over cheapish ammo
Still not ejecting perfect. 4 to 5 o’clock is my best guess, I was too busy shooting. 
I don’t want an adjustable gas block if I can avoid it.
I saved all my brass, but haven’t looked at it yet…
Growing up I never really considered myself smart or intelligent. I hated school and my grades showed it. It wasn’t that I couldn’t do it I just didn’t care. I did go to college after switching over from the Army to the Guard. I when I was paying my way my grades really improved. I have been an avid reader all my life. I don’t know if in my 50’s that I have really gained some intelligence. It is more likely that many of the people that are around me and in this Country have just become a lot dumber. Either way I am a jack of all trades and the master of none. There is nothing that I won’t tackle if I can learn a new skill from it. I never mind sharing a little experience or knowledge if I can because so many have done the same to me. This is one reason that I like being on forums. I am always learning something new. I am glad we were able to help you figure your problem out. 
But apparently I’m not smart enough
I’m more mechanical than book smart, but sometimes I over complicate things, or simply overlook the obvious.
Again, I appreciate the help. If I’m not learning, life is pointless. 
