AR Platform Offset Buffer Retainer

posted in: Firearms | 45

Those of you that have had the ‘problem’ know that damaged buffer faces are caused by an out-of-spec buffer retainer pin location. 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.


USA Sales Only


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


USA Sales Only






45 Responses

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

  2. Ahmad Aboukar

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

  3. 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.

  4. 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!

  5. 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.

  6. 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.

  7. 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!

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

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

  10. Still available? Also when could I expect the pin to be shipped?

  11. Sorry just read the feedback. Had to turn my phone sidways. Be back soon.

  12. 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.

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

    • Yep, still available. Tnx.

      • Just ordered 2!

        • Excellent! Let us know how they work out for you.

          • 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.

          • 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.

          • “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!

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

  15. I hope you still have some, I just ordered a couple. 🙂

  16. 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 $$$$.

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

    • 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!

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

    • 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.

  18. I just tested it and it seems to work. The Paypal account is Send me an email (same address) if it doesn’t work.

  19. Will Griggers

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

  20. 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.

  21. Bill St Jeor

    Would like to know if these offset pins are still available.

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