I bought a Nova last weekend and then an extended magazine kit for it.

  I was able to get 5 shells in the magazine but the 6th slipped part way in and no more.  I've heard of other having this problem too.  I loosened up the extension tube 3 or 4 half turns.  I was able to slip 7 shells in, I then tightened down the extension and cycled the rounds out.

 All 7 shells now go into the magazine tube will little effort.

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