Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • jaekelopterus

    Do you mean the AR-10 platform, or the .308 cartridge?

    • jaekelopterus, both, it is designed for AR-10s chambered in .308 (AR-10 type guns these days come chambered in all sorts of cartridges).

  • jaekelopterus

    Sorry, Steve, that was addressed to Harry. I’ve had the chance to play with an AR-10 in .308 and it did exactly what it was supposed to do very well.

  • viper5552

    sorry for the stupid question, but what is the advantage of the hydraulic buffer over the conventional spring buffer?

  • Harry, it has been around for 50 years. It may not the most modern cartridge, but it is a standard and I think will be in production for at least the next 100 years.

  • Thomas

    If this is an hydraulic buffer.. i asume it has oil in it like a cars shock absorber .. Do these leak oil over time and use ? Do they work as advertised ?

  • Harry

    The 308 was used in ww1 lee enfields I think and sorry I forgot to do my reserch. Due to the fact that I live in Australia I don’t own a gun but I’m more into millitary guns. I’m just saying that the 308 is a bit to old to be put In modern day assult rifles when there is rounds like the 6.5 grendal out there.

    • Harry, look, I will be frank with you: please do not argue about the guns with gun owners when you are not a gun owner yourself. Guns and their history are complex. You are most welcome to read the blog and learn more.

      The .308 was invented in the 1950s.

      • Edmund Charles

        Let’s direct our friend and firearms enthusiast into some professional reading and learning media.

    • Edmund Charles

      .303 was used in The Great War/WWI, the 308 was invented post WWII and the military designation is 7.62 X 52 (40 caliber)

    • Edmund Charles


      It’s ‘too old’ (grammar – as in excessive); since the advent of smokeless powders, many cartridges designed and used 100+ years ago as still very adequate and most deadly. The .30 caliber cartridges were studied by all the western powers after The Great War/WWI and it was realized that the existing cartridges were ‘too much of a good thing’ in the sense that the lethality of the bullet far exceeded both the range engagement and the ability of he conscripted soldier to use these cartridges to their maximum potential (save for that of crew machine guns). Yet the practical economic reality of post-WWI was that any existing stockage of ammo was to be sufficient for any next war, if there was to be any major next war that is, for The Great War was thought to be the last major modern conflict in Europe (how sinfully naive was the world and it still remains). Thus huge hundreds of millions of perfectly adequate and powerful .303, 8mm and 30.06 ammunition was retained in the inventories of the great western nation’s arsenals. With the advent of WWII, these same ammunition stocks served all major combatants well. It was only with the Cold War and the rise of NATO that a need rifle and machine gun round was engineered for the purpose of universality and to dispel any nationalistic prejudices for one round over another, thus a ‘new sheet’ was created for the new NATO rifle and medium machine gun- the 7.62 X 51 (commercial .308). The shame was that NATO did not go far enough! They should also have re-engineered a new pistol/sub-machine gun round, something in 40 or 42 caliber and possessing a high velocity of 1,200 – 1300 fps. Yet this was not to be.

      For additional education I would recommend the reading of Ian Hogg late of Her Majesty’s Royal artillery Service, authority on modern weapons and senior British Army senior NCO. His writing style is clear, concise and most entertaining. Learn well and enjoy a life of sober rationality while other think and speak gibberish.

  • c. trapp

    I do not own a firearm.
    I’m guessing wildly based on what I learned whlie studying mechanical engineering.
    I rely on Steve to block this comment if I’m writing BS.

    @viper5552: This thing looks like it is used in addition to a spring. I think it acts as a guide rod for the original recoil spring. It seems to work like this: When travelling rearwards, the bolt carrier compresses the recoil spring and eventually hits the black front part of the device. Instead of slamming to a stop the buffer takes over by being pushed together. The motion is slowed down by a plunger which has to move through oil inside the buffer (this would be the “hydraulic” part). When the buffer is fully compressed (or all the kinetic energy of the bolt carrier has been dissipated by the oil, whichever happens first) the bolt carrier comes to a stop and the recoil spring (and a spring inside the buffer) begin to push it forward.
    The inteded effect is to convert the “kick” of the rifle to a “shove” which not only increases ergonomics but is supposed to to reduce wear (by vibration) on the weapon (Manufacturer claim).
    Possible problems are changing characteristics when in use due to changing viscosity of the oil when it becomes warm, timing problems (only in full auto when the buffer doesn’t fully expand between shots) and a change in weapon balance and weight (which shouldn’t matter much)

    Sorry for all the parenthesis, c. trapp

  • mark

    I’ve seen hydraulic buffers for the AR-15/M-16 series rifles, but they were never popular. Were they not popular due to poor performance/heavy weight/high cost (or a combination)?

    It seems like hydraulics might have a small advantage over a simple spring, but only for competition rifles. You could control the rebound of the bolt, and the rifle would get a little heavier in the back, which wouldn’t be bad for some types of shootin.

  • Erik

    @Harry, what the heck? .303 British was used in Lee Enfields. It is still in use in some countries even, although India made a 7.62x51MM Chambered SMLE No 4. Mk 1 that can handle a .308 Win. I have been looking to pick one up.

    .308 is one of the best/most versatile cartridges out there, I’d take one over any of the “intermediate” carbine cartridges out there, including 6.5 and 6.8.

  • Whatever

    From the Buffer Technologies website: “Each carefully designed buffer is made from a polyurethane with specific shock-absorbing properties.”

    So this sounds more like a buffer, something that will keep the bolt carrier from harshly hitting bottom rather than a shock absorber (which are better referred to as dampers).

  • Crapsworth

    I had an enidyne(sp?) buffer on my first AR15 build. It seemed really cool, but I never noticed any difference between the oil filled buffer and the nearly stock rifle sized buffer. I would imagine that a perceptable difference might be found with a heavier round like the .308.

  • I have an Endine hydraulic buffer for an AR-15, though I will unload it as soon as I get a chance if I can some money for it.

    Reviewed it here:

    Two stage recoil – I think it’s the urethane buffer hitting the end of the buffer tube, and then the piston bottoms out. It feels weird, I don’t like it. It didn’t seem to reduce muzzle flip any noticeable amount.

    Also, the bolt only occasionally locks back after the last round.

    • Suburban, lack of bolt hold open would be very annoying!

  • SKIP

    hi i have a armalite ar10 308 im thinking about getting a hydraulic buffer tube for my rifle. i dont know to much about them but i see whats in my a2 butt stock and its a cheap spring with a normal buffer tube. i bought a polished spring thats cut different and has better coils it looks and feels so much better than what was in my ar 10 im just going to try my rifle with just this new spring it was 25.00 dollar spring but it made well and has less twang than the armalite spring. it seems like alot of money for a spring but i have used springs in my job for 25 years and i can tell you that better springs have alway worked better for be than the cheap ones.
    And i bet you ill have less recoil with the new spring and the buffer tube that came with the rifle. im going to try this first before i buy a buffer tube with oil in it that cost 100.00 dollars. the spring is 7 percent stronger than the old one it dont seem like much but i beting on the spring to help with the twang and reduse the recoil some because my ar10 308 does not have much of a kick any way. all i need now is a way to put a rubber butt pad on a a2 butt stock if anyone know how to get one and put it on a a2 butt stock i would like to hear how you did it without having to slide a butt pad over the stock. i just want one to go over the plastic a2 butt stock without making it look bad. so if anyone can help me out i will be looking for your post thanks keep it in the 10 ring hope to hear from someone soon. skip 6/28/12