Q: I am currently trying to get a super safety to work with district industries PDW stock. I'm getting light strikes and according to atrius this is usually caused by the buffer and spring not being heavy enough. Is the heavy option buffer and spring heavier than What comes from strike industries?

Asked by: Andrew Martin - 5/6/2026
A: You would need the our Strikes Industries Viper Kit: buffer tube, spring and buffer. This will still not get you to run a super safe to run reliability though. What we have found that ties it all together is our Enhanced Bolt Carriers, we have a polymer that we use on the end that absorbs some of the shock which prevents carrier bounce. We have known this due to we run full auto, but now that FRT's are on the market this is what our customers use to resolve their FRT issues. This is a link to our Enhanced Bolt Carriers and on that page is a video that shows our founder demonstrating our Enhanced Bolt Carrier with a FRT compared to an all steel carrier. https://www.blackriflearms.com/ENHANCED-BOLT-CARRIERS-_c_10.html
Answer provided by: Administrator (5/8/2026)

Q: Is there an H3 buffer option?

Asked by: ace case 438 - 7/27/2025
A: Sorry we do not offer an H3 PDW buffer.
Answer provided by: Administrator (8/1/2025)

Q: Is there ears for the buffer retaining pin? It doesn't show in the picture and I have seen the original viper tube has them and why this one doesn't have it?

Asked by: johnjohnlepocon - 9/29/2024
A: You do not need the ears to go around the retaining pin, the ears do not hold the retaining pin in place so we designed it just like a mil-spec receiver extension/buffer tube.
Answer provided by: Administrator (10/1/2024)

Q: I’m running 7.5” 300blk suppressed with strike industries pdw brace having cycling issues also added adjustable gas block still has not fixed the problem. Would this kit do the job and if so which buffer and spring should I go with?

Asked by: Jake - 8/12/2024
A: We don't know how your firearm is gassed so we can't give you an definitive answer; however, some customers with similar builds have found that Enhanced Compact Buffer Tube with Light Spring & Carbine or H2 buffer has resolved similar issues.
Answer provided by: Administrator (8/29/2024)

Q: Is the pistol caliber buffer only compatible with pistol caliber? Is it because if the size of the round (ie dimensions)? Or can it fit in a 5.56 system. I am curious because the weight is similar to that of a H4 buffer. Would like the benefits of a heavier buffer. Thank you

Asked by: Zulu - 5/14/2024
A: Yes pistol buffer is only for pistol calibers.
Answer provided by: Administrator (5/20/2024)

Q: What make the included buffer tube different than the one from Strike Industries so that it can accept the buffers included in your kit?

Asked by: Luz - 5/14/2024
A: Our spring and buffers are of different dimensions than the Viper PDW. Our buffers will not work with Strikes springs.
Answer provided by: Black Rifle Arms Sales Team (6/17/2024)

Q: Hello, is it possible to drop in a 3rd party buffer into this system if need be? For example if I want to use a standard H3 or H4 buffer? Are the buffers in this kit industry standard buffers? Thank you

Asked by: Zulu - 5/8/2024
A: No you can't. The whole kit is a PDW that was specc'd out to work in combination with each other. You can't mix mil-spec and PDW with this kit.
Answer provided by: Black Rifle Arms Sales Team (5/8/2024)

Q: I have a 5.5 ar chambered in 9mm. It is select fire. Which buffer weight would be recommended? The h2 or the pistol?

Asked by: Jimmy Zaragoza - 2/26/2024
A: The pistol buffer is meant for pistol caliber AR-15, so pistol buffer would be what you need to select for your setup.
Answer provided by: Administrator (2/28/2024)

Q: I have a 5” 5.56 what weight buffer would I need? And the stock viper tube length won’t work?

Asked by: Jay - 1/10/2024
A: Typically and most likely a H2 buffer; however, we can't guarantee that is what you would need as we don't know how your firearm is gassed. Yes you have to use our buffer tube to make the system work.
Answer provided by: Administrator (1/10/2024)

Q: If I have the viper pdw brace already, do I have to get the tube and spring also or can I purchase the buffer alone? Also is the cqb buffer compatible with the hbpdw honey badger brace?

Asked by: Karl Chambers - 11/24/2023
A: You have to buy the kit in order for the setup to work. All the components are finely tuned (specc'd) to work together.
Answer provided by: Black Rifle Arms Sales Team (11/24/2023)

Q: I have another question. The buffer tube, does it have the little teeth like things to hold the detect in place? From the picture I don’t see if it does or not.

Asked by: Eddie - 11/1/2023
A: No it's not a feature on the buffer tube. As long as your tube is secured properly with the castle nut your tube is not going to move.
Answer provided by: Administrator (11/8/2023)

Q: Does the buffer tube have the part where it goes over the buffer retainer?

Asked by: Elliott - 11/1/2023
A: No that is not a feature on our PDW buffer tube. If buffer tube is secured properly with the castle nut your buffer tube is not going to move.
Answer provided by: Administrator (11/8/2023)

Q: When it says choose buffer do I click on carbine buffer or just leave it on the first option where it says “PDW Enhanced Buffer V Tube, Spring & 1-Qty Buffer”? I don’t need the pistol buffer. I just want to make sure that I choose the right option. So if I click on carbine buffer I will still get the tube, spring and buffer? Sorry I’m new to ordering items online.

Asked by: Elliott hoa - 10/23/2023
A: You need to click on Carbine Buffer to select that buffer weight.
Answer provided by: Administrator (10/24/2023)

Q: Hi I just watched your video on YouTube, I just would like to know does it work fine with 7.62x39 5.5" barrel full auto??

Asked by: Armourer Dean - 10/1/2023
A: It has ran 100% reliable on every short barrel machinegun we have ran it on, and never received a report that anyone had issues running the PDW Viper Assembly Kit with a H2 buffer on select fire AR-15.
Answer provided by: Administrator (10/27/2023)

Q: Do all the options come with a buffer tube. I'm confused and the description it's pretty vague on what's included with the 3 different options. I need a new buffer tube for my viper pdw. Does the first option include the buffer tube as well?

Asked by: Alex V. - 8/22/2023
A: With this package you get the buffer tube, spring and then you get to choose 1 weight size buffer either the Pistol Buffer, Carbine Buffer or H2 Buffer (we are currently out of H2 buffers so this option will not show in the drop down box under Buffer Weight Option).
Answer provided by: Administrator (8/23/2023)

Q: Does the tube have the same QD slot and drainage hole like the original tube from SI?

Asked by: Steven - 5/12/2023
A: We have a drain hole, but we do not have the QD Slot on the buffer. In order to do the QD slot we would have to make our buffer tubes longer and with SI having the QD slot on the brace body we feel leaving the buffer tube length as compact as possible is what most customers are looking for.
Answer provided by: Administrator (5/24/2023)

Q: I have a ks-47. Will the carbine tube work for my pistol?

Asked by: RONALD SMITH - 4/26/2023
A: Yes the kit will work on the KS47
Answer provided by: Administrator (4/27/2023)

Q: Does this include the buffer tube

Asked by: Shawn Sherman - 2/7/2023
A: Yes it includes the buffer tube
Answer provided by: Administrator (2/7/2023)

Q: I’m running the brace on a suppressed 300 blackout, I’m having buffer issues with stock buffer and wondering should I go lighter or heavier in weight too get subsonic ammo to cycle

Asked by: Antonio Lee Hinkle - 1/29/2023
A: There are questions that we would need to ask in order to direct you. Please call us during normal business hours Monday thru Friday 9am to 4pm EST at 386-410-5162.
Answer provided by: Administrator (2/7/2023)

Q: Will any of these help with a 300blk build? Or are they stiffer springs.

Asked by: Gw - 12/30/2022
A: Sorry for the delay in response. Can you please call tech support and ask for Charles, Charles would need to ask some question to advise you what your set up would need. He will be in office Wednesday and Thursday: 386-410-5162
Answer provided by: Administrator (1/16/2023)

Q: What buffer would you recommend to use this kit on a 7.62x39 with a 8.5 inch barrel? Thanks

Asked by: Raymond Juarez - 9/13/2022
A: Depends on how it is gassed so either carbine or h2. We run ours on h2.
Answer provided by: Black Rifle Arms Sales Team (12/20/2022)

Q: When will the H2 spring and tube combo be in stock?

Asked by: KrisM - 9/7/2022
A: Sorry we missed your question. We were working on building a hybrid stock for this PDW so if ATF banned them you could take the Strikes stock off and use the tube for pistol so we have made some changes and expect it to go back back in stock sometime this coming January.
Answer provided by: Black Rifle Arms Sales Team (12/20/2022)

Q: will this work with the SB sbpdw brace? thank you

Asked by: Don Smith - 4/25/2022
A: No it's not compatible.
Answer provided by: Black Rifle Arms Sales Team (5/2/2022)