To construct your very own homemade silencer, you will need:

A square yard of strong and flexible matting: fibreglass for preference...

A foot of ¼ inch car brake line.

A powerful epoxy resin, with the mashed-up-horse hardener.

A drill rod or cut dowel to fit the inside dimension of the barrel.  Snugly.  This is important.

A foot of 1½ inch PVC piping with a pair of end caps.

Six small wood screws.

A couple of sandpaper sheets.

Two quarter-inch-or-smaller-diameter drill bits.

Razorblades, elastic bands, masking tape, rubber gloves, a spare afternoon and somewhere private.

This is all in books.  This is all over the Internet like acne.

Borrowed wisdom.

Here's one I made earlier.

Good for four hundred rounds, give or take, and your upstairs-downstairs neighbours needn't know a thing.  This tall bastard, his brains look like clay mixed with cat food.

I always think of spitting, times like this.  A glob of saliva hitting a hard surface.  A hand slapping a book on a desk.  Bubblegum popping.

Spwk-spwk-spwk-spwk.

That's what your silencer does.

This is not like in the films.  This is not like the popular Hollywood impression that a muffled weapon makes the same noise as an industrial crop-sprayer.

Ffft-ffft-ffft-ffft.

This noise is what could affectionately be called: wrong.