AR Platform Offset Buffer Retainer

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Those of you that have had the ‘problem’ know that damaged buffer faces are caused by an out-of-spec buffer retainer pin location or even a bolt carrier. And it doesn’t take much! A ‘beat up’ buffer face is mostly cosmetic, but the more serious issue is if the constant pounding on the pin will eventually shear it off its base and end up somewhere around the trigger control group. Maybe even cause a jamb? I suppose it could.


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Buffer Face 1a

Buffer Retainer Pin _ stock_a


As you can see, it’s a problem. The first thing you should do is take it up with the firearms manufacturer to have them correct their problem. It IS their problem. So here’s what the buffer retainer does. Nothing but hold the buffer and spring slightly compressed in place so it doesn’t ‘spring out’ during the take-down process. That’s it! It’s not supposed to come in contact with the buffer during the firing and cycling process. It’s really there for convenience, to simplify one’s life so to speak. You can actually remove the retainer and retainer spring and the AR will function just fine. Of course, when you forget you’ve removed the pin is when the buffer will fly out on you during your next cleaning. Don’t ask me how I know… lol.


So, I decided it’s time to design an easy fix. An offset pin would be perfect, right? It would allow the buffer to move further forward and contact the bolt carrier properly and get pushed back off the pin upon reassembly. And it works! I whipped up a new buffer retainer in CAD software and had a few produced. Here’s the drawings. Note the ‘shelf’ which I added to keep the retainer from spinning in place. The buffer tube rests on the lowered shelf shown and the retainer can no longer spin in place.

BR_3D_3   BR_3D_1

So moving on to the machine shop results. Perfect! I was concerned that such a small part might present lathing/machining issues, but everything measured dead on. Impressive. I received the parts in steel, and then blued them for those that might be interested in buying one. Here are more pics…

This pic shows the effect of a properly functioning retainer. The bolt carrier contacts the buffer and pushes it back when fully assembled. That keeps the buffer from slamming into the pin during cycling.



Offset buffer retainer. Now in stainless steel.


And the retainer installed. Note the shelf, or ledge, contacts the buffer tube itself and prevents the pin from rotating.



The buffer and buffer spring installed. Note this is a new buffer and will be testing the results over time. I’m pretty confident it will function as designed.


                                                                Patent Pending


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95 Responses

  1. Jason Mares

    Chris, what should you do with an extension that has a notch for the buffer detent? I guess you can’t use the new buffer’s shelf but rather screw the tube the whole way until the pin is captured by the notch? Thanks in advance.
    Jason M

    PS. Didn’t mean to reply to an older post, sorry.

    • Chris

      I had to look up those buffer tubes and saw some listed, but not really sure what the point is for the notch, unless it’s just to let you screw the tube in further. Maybe someone will jump in and let us know. I suppose you could just grind the face of the tube until the notch is gone. I saw one tube where the notch was flared out a bit, so you could grind that off without hitting the threads. If you’re going to come close to the threads, put the castle nut on first and use it as a thread chase when you’re done. Let me know what you decided to do and how it worked out.

      • Jason M

        Thanks Chris, worked out great. I took a file to the RE’s retainer notch and made it smooth. The offset buffer worked out great. Thank you Sir!

  2. Dan

    I wanted to update you on the offset buffer pin install. I got both pins very quickly. After installing the one on my JD Machine .308, the buffer and BCG now touch as they should. I haven’t gone to the range yet, but I am looking forward to shooting this rifle without busting parts. I checked head space again, just to make sure it wasn’t part of a larger issue. This offset retainer pin should do the trick.

  3. Chris

    Still waiting on delivery. They were supposed to be here yesterday, the 29th, but UPS issued a “late UPS trailer arrival has delayed delivery” notice. Terrific.

      • Alex

        My Offset Retainer came in today. I have installed it and tested it by charging and dry firing a couple dozen times. Seems to work! Thank you!

  4. Dan

    I saw that the November 24th date was yesterday. Did I miss this batch? I hav a .308 build that I need to finish and it is slightly out of spec. I will be patient. Haha

    • Chris

      Nope, they screwed up about the 24th because of the holiday. They will ship them out tomorrow, Monday. We’ll see….

    • Chris

      When they become available you’ll see the Paypal button a couple places on the page. The machinist pushed the delivery date out a bit, and is now saying Nov. 24th.

  5. Dan

    I need one of these for a LR-308 build. I hope you order enough for me to buy two of them.

  6. Chris

    Ordered more pins today. I hope I don’t run out before they get here! Sales are crazy. I guess there’s a real problem out there!

    • Chris

      Shipping is scheduled for Nov. 17th. The Paypal link will be up when they arrive here.

        • Chris

          Yes, but back-ordered. They should be here soon, I hope. I’ll have the Paypal button back up when they arrive. Tnx.

  7. Chris

    Offset Buffer pin sales have been crazy. I thought there would be just a few dozen or so with issues, but it appears that manufacturers have trashed the concept of precision manufacturing and released a horde of out of spec lowers or bolt carriers. Crazy. Although it’s not a critical or even necessary component, by God, try to make it right. It’s not that hard, and it shows a lack of interest in complying with specification standards. It’s hard to believe that manufacturers leave it to the individual buyers to resolve these issues on their own when they know full well of the cause and lack of interest within their own manufacturing facilities. Lazy is the operative word. Either that or a complete lack of understanding of the products they produce. Sad as shit if you ask me.

  8. Charles

    Ordered 2 – really fast shipping. Well made. The retainer pin tip is thicker than a standard one. It fit nicely with my Magpul UBR. I like the offset. Does was says. Helps keep the buffer off the pin with the receiver is closed. Will be ordering more – Thanks

  9. Chris

    Shipping has changed. Too many Tyvek envelopes getting torn up and ripping out the pin(s). Now shipping as First class package. Sorry, but no choice. You’ll have tracking info now.

    • Greg Mantei

      Chris , I just bought a Ruger AR 5.56 and with just 90 rounds in it that Pin has my Buffer all dinged up . Sent it back to Ruger were they replaced the Buffer and said that it was Normal ! Of course I don’t believe that for a second . I would like too Buy 2 of your offset Pins. But don’t do a PayPal . Can you do a Check, money order , C.C or something. I really could use these Pins . Greg …..

      • Chris

        I cancelled the Paypal invoice and left you my mailing address since you don’t want to use Paypal. A USPS money order will be fine. Tnx.

    • Chris

      Depends where you’re located. USPS claims 3 days, and you know they’re always right.

  10. Chris

    Thanks for all the offset buffer retainer pin orders, and I hope they’ve helped everyone out. Please let me know if your Tyvek envelope arrives all beat to hell. I add additional postage and rubber stamp them with Please Hand Cancel, but I guess they miss some. Or perhaps don’t care? I’m trying to avoid shipping as a “package” since postage is then about $3 instead of 70 cents.

    • Shawn Holbrook

      Ordered 2 of these but never got confirmation or shipping info. Money was taken from my account but no other info ??

      • Chris

        I sent you notification the day of your order that it was being shipped that day. These go out as regular 1st class mail, so there are is no tracking info. If you don’t receive the pins in the next few days, please let me know. Tnx.


      • Chris

        I double checked, and it was mailed 3 days ago on the 24th. I’m in N.C. USPS states an average of 3 days for delivery. Never know, though, right… 🙁

        • Shawn Holbrook

          Still haven’t received them. Don’t understand how it can take this long??

          • Chris

            I don’t know, either, and I have no control. I’ll send you another one if it doesn’t show up in the next couple days. Tnx.

          • Chris

            I checked, and USPS won’t do a “find mail” search unless it’s been 7 days.

    • Shawn Holbrook

      Chris I don’t understand why I can’t view your last response??

      • Chris

        Not sure. Try clearing your browser cache, or use a simple package like Glary Utilities to clean up your system. Various browsers also let you clear histories to give you a fresh start.

        • Shawn Holbrook

          Hey thanks Chris. I was able to view you response on my iPad. For some reason I couldn’t see it on my phone. I hope it doesn’t have to come down to you sending me another one. Hopefully it’ll show up in the next day or so. This isn’t the first time I’ve had issues with usps. I once received a package like 2 weeks late. Who knows?

        • Shawn Holbrook

          Hey Chris I received the pins yesterday and installed one on my problem lower and it definitely gave me the little extra space needed. Thumbs way up on your product!! Thank you

  11. Chris

    Temporarily out of stock. The latest shipment from the machine shop came in out-of-spec. It’ll probably be another 20 days unless they put a rush on it. Sorry.

      • Chris

        Right here. They should be ready to ship the week of Aug 7. The Paypal link will be up when they’re ready.

        • Chris

          The new pins are here and they look good and within spec. Let’s drink bourbon and go shooting!

  12. Chris

    Hey folks. I hope your offset buffer retainers are working great for you. I just placed another order for more and will have them in hand soon. No surprises with 40-day turnarounds this time, thank goodness, but I still have some in stock just in case. I’ve been pretty bad about getting the ‘word’ out there on these things, so if you’re happy, please spread the news. Tnx!

    • William Campbell

      Just paid@paypal for 1 offset buffer retainer pin. No invoice or confirmation # provided. Please advise status

    • Dan Nygren

      Hey Chris…

      Just found out my AR-308 has an issue… Your offset pin seems to be the fix so I placed an order. Thanks for offering these!! If possible, please let me know when it ships.


  13. Robert Stewart

    Just ordered two. I’m new to AR’s….wanted one for years but didn’t “pull the trigger!” After I got one I soon decided to add a dual sided attachment for a sling. Many problems ensued, owing to not enough depth when screwing the tube back in. The buffer retainer spring and pin kept coming out. While I ultimately diagnosed and fixed it I worried that this tiny little part could be troublesome in the future. I read about sheared off pins. I’m looking forward to swapping out my pin with your improvement.

  14. Rob

    Thanks very much. Pins arrived in 2 days. I could see the better fit against the buffer right away. Thanks for making these.

  15. Ahmad Aboukar

    Just wanted to say thank you for continuously producing these! There’s always gonna be a buyer out there 🙂

  16. AO

    Perfect solution for out of spec retainer hole. I had to file the buffer tube just a hair so that the new pin could move freely. Item was promptly shipped. Thanks for making these available.

  17. Joel

    Fitment is spot on, works very well, shipped and arrived in a timely matter. Being in Kalifornia I can no longer purchase another stripped lower so this thing really saved my ass! for 15 dollars this is a no brainer. Thanks for making this!

  18. Steve

    Not having an issue yet. Just ordered two for two new builds that are in progress. Looks like a great solution. Thanks for designing these and making them available.

  19. Brandon

    5 Stars! This was exactly as advertised and cured my AR. I have a lower from a well known manufacturer that had the retaining pin hole drilled too far to the rear as described in the article above. Received the pin a couple business days after ordering. Filed a couple thousandths off the top of the pin (slightly taller than needed) and installed without incident. Works just as advertised and now the rear of the carrier pushes the buffer back when I close the lower just as it should. Would definitely buy again.

  20. Henry Jones Jr.

    Wow-thank you for making these! I have an Anderson AR lower with the hole machined in just about the same spot as your last picture. I was going to strip the rifle down and buy another lower, but this is a LOT easier to deal with!

  21. Ryan

    Just came across this thread, curious if you have these still available. Thanks!

  22. Jack

    Just sent you an email, wondering about shipping to canada. I hope you still have some of these available!

  23. Howard

    Id like feed back in how these are working too I have the same problem very minor but fustrating. Ill probably be picking one up towards the end of the week.

  24. Tyler

    Am I correct in assuming you still have these available? I’ll need two if you do.

          • Tyler

            Retainer works well so far! I have one installed, and it’s keeping the buffer off the pin. One thing I noticed Is that the pin that retains the buffer seems to be a little long, as I had issues getting the spring past it. Overall, it acomplishes what it is supposed to do, and does it well.

          • Chris

            It is a tad longer because of the anti-rotating shelf depth. I have plans to adjust that on the next batch, but so far it seems to work ok as is. Bolt carriers seem to have enough clearance to allow for the height as is, but getting closer to spec would lessen potential for problems. It seems to be doing the job for stopping buffer face damage, so that’s pretty awesome. Thanks for sharing your experiences! Fortunately, anyone can file down the pin height to suit, if needed.

          • Tyler

            “Fortunately, anyone can file down the pin height to suit, if needed.”

            I truly agree with this statement, as the longer pin doesn’t really need to be any shorter to work. I ended up leaving both of them alone, since I would rather have a harder time getting the spring out than having the pin be too short.

            I definitely agree that these work the way they’re designed, and I would like to thank you for designing a solution to a very annoying problem!

  25. Justin

    Do you still have these in stock? I may need to order one for an Anderson arms lower

  26. Pranqster

    This is ingenious! I am surprised that no-one else has come up with this before, I hope that you continue to produce these, and that your creativity is rewarded $$$$.

  27. Jayson

    Are these still available or do you know when more will be available? Thanks.

    • Jayson

      Sorry, but wanted to also ask, do you know approximately how much of an offset this new pin will give? Between 1/16″ and 1/8″? Thanks in advance!

      • Chris

        The pin itself is the same as the stock retainer, or .1″ in diameter. It is offset about the same diameter of the pin.

    • Chris

      Yep, still have about a dozen of these. Will make more, but wanted to feedback to see if they should be left as is of refined.

  28. Will Griggers

    I can seem to make he PayPal button work. How else can I order pins?

  29. chad

    Awesome! thank you, this is exactly what I needed. I was just starting to figure out how i was going to make an offset buffer retainer but you saved me a ton of time and worry.

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