AR 15 Piston conversion

Discussion in 'Shooting, Hunting and Fishing' started by stoatman, Feb 4, 2010.

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  1. An acquaintance of mine has just had a piston conversion done on his 7.62 x 39 AR 15, and it was written up in a Dutch shooting magazine.

    2 things were notable was the conversion had been done, apparently: the rifle was indeed less accurate than it had been, and the felt recoil impulse was changed. Apparently the recoil impulse had lost some of the characteristic softness of the gas tube AR.

    What also will be interesting to see is whether, with long-term use, the bottom part of the upper receiver will wear disproportionately because of the now asymmetric distribution of forces on the carrier during the rearward stroke.
  2. So in short they have fücked up their perfectly good AR? What was supposed advantage of having it done in the first place?
  3. After Delta and other tier 1 SF in the US adopted the HK416, these piston conversions have become all the rage with the 'mall ninjas' over the pond. Just about every manufacturer is now churning out conversion kits or fully built piston guns.

    The main point is that a piston driven AR15 is supposed to be more reliable, because it takes away the in-built 'sh1ts where it eats' fouling of the direct gas mechanism.

    In the better designed ones like the HK416, this is indeed the case, but many of the conversions are poorly executed, giving rise to excessive stresses and 'carrier tilt' as described by stoaty.
  4. Reliability over many shots due to fouling.

    Which is not an issue at an IPSC match since you're not firing enough rounds to get the Rifle hot enough and dirty enough for it to be a problem.

    I don't believe even the DSR guys suffer this problem, and they are firing 80-100 rounds in under 4 minutes... unless their rifles are filthy and not correctly lubricated before they even start.

    It seems to be just a bit of a toy, particularly for people who can't be bothered to clean their Rifle moderately well.
  5. If it aint broke-----
  6. Right.... so when the the US Army ran a reliability test on the M4, and it (the only direct gas weapon) had more stoppages than all the other weapons in the test put together, you feel this was:

    a) nothing to do with direct gas
    b) all down to bad cleaning
  7. We're talking here about sport shooters who don't put enough rounds down fast enough for it to be an issue.

    There is no doubt of its military applicability.