I'll start by saying I love my a400, but it does have a fatal flaw if treated poorly. Back in 2017 my brother's a400 was leaning against a wall, got knocked down and the receiver and stock split at the stock tube bolt. This year I got my a400 used and was excited to take it on the first diver hunt of the year. Sure enough we were setting out decoys, hit a wave and buddy lost his balance, stepped right on my gun case and split my gun in the same place, same fault. Unfortunately no warranty coverage. Stoeger can provide the entire stock tube bolt for 179+shipping or the end cap of the tube that threads into the receiver for 9.95. Double unfortunately, the steel rod (bolt buffer) was broken in 2 as well and they don't offer a replacement part. I spoke to stoeger and they said it's acceptable to run the gun without the buffer if you don't plan on using 3 1/2" magnum, otherwise, replace the entire assembly. Being a self made man with resources I decided to make the bolt buffer. From what I can tell the piece is made of mild steel with a thick case hardening and a hdpe insert in the rear where it contacts the damper in the stock itself. It's a simple part to spin up and its getting me back in the game and time will tell if it's an acceptable replacement or not. Here's to the diy grey beards out there 
