|  | Hmmm, GPMG == General Purpose Machine Gun?
If so, machine guns (particularly the belt fed ones) tend to be much 
heavier than the individual shoulder arm.  That absorbs recoil.  Too the 
actions of such guns are designed to take up recoil somewhat more 
effectively than that of a shoulder rifle which is designed primarily for 
accuracy.  Accuracy, while important in a MG, isn't THAT important.  You 
are after all throwing alot of lead downrange at one time.  I was trained 
to fire in a minimum of 6 round bursts on a MG, its the volume of fire that 
get the kills.
One of the more pleasent experiances I ever had with a machine gun was with 
the Bren.  Pleasent because it not only had light recoil (helped somewhat 
by the bipod) but was also very accurate.  It was so accurate that my 
instructors at Bragg classed it functionally as an automatic rifle rather 
than a MG.
Rich
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|  |     More to the point of .0's question, most light/gp machineguns have
    buffers built in. The former NATO standard rifles in 7.62 do not.
    They are standard semi-automatic weapons and the full effect of the
    recoil is transmitted to the shoulder. For instance, the US M14 in
    the Auto configuration had a heavier spring on the operating rod,
    but the M60 LMG has a liquid filled buffer in the butt stock. The
    US M16 and (I beleive) the new SAW also employ buffer assemblies.
    In other words, the older weapons had strictly mechanical operating
    assemblies that simply slammed the bolt to the rear and the operator
    was the buffer 8-).
    
    Bob Mc
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