You're taking the coderef fine, but you don't show us how you're using it. To use a coderef as a method, you need to can manually pass the object as the first arg. Here's an example:

  {
    package foo;
    sub new { bless {}, shift }
    sub foo { ++$_[0]{foo} }
  }

  $foo = foo->new;
  $cr = \&foo::foo;

  print $cr->($foo), "\n" for 1 .. 5;
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Perhaps if you post the code where you try to use the coderef, we can give a less general answer.

Update: You can also wrap the method call in an anonymous subroutine, if you'd prefer that:

  {
    package foo;
    sub new { bless {}, shift }
    sub foo { ++$_[0]{foo} }
  }

  $foo = foo->new;
  $cr = sub { $foo->foo(@_) };

  print $cr->(), "\n" for 1 .. 5;
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Update: fixed to reflect chromatic's reply