gap inthe cocking tube and the sleeve

[roland3]

can someone elaborate a little on this gap and exactly where it is . i m having trouble understanding where this gap is and needs to be. pics or diagram would be helpful. i was reading the instructions on the build process in the sitcky above.

[97th Signalman]

can someone elaborate a little on this gap and exactly where it is . i m having trouble understanding where this gap is and needs to be. pics or diagram would be helpful. i was reading the instructions on the build process in the sitcky above.

The cocking handle is what you grasp and pull on the forend of the left side of the CETME/HK cocking tube to pull it back and cock the rifle. The cocking handle is attached to the cocking piece with a pin. As you first lift and then pull the cocking handle to the rear it is the cocking piece inside the cocking tube that actually pushes the front of the bolt carrier to drive the bolt back and cock the hammer. The .020" gap that you hear mentioned is the gap between the cocking piece and the bolt carrier when they are both in the full foward position. As the forward end of the bolt carrier actually fits inside back end of the cocking piece (think of the cocking piece as a socket for the bolt carrier extention) so that the actual gap is hidden. What you really want is about .020" of free movement or play between the two and it is that free play that you are actually measuring. If you have no free movement at all when they are both in the forward position and they are actually in contact with one another then the cocking piece may be holding the bolt carrier somewhat to the rear thereby exagerating the bolt gap (a different gap) and giving you a false indication of that critical parameter. If you have way too much cocking handle gap then raising the handle away from the cocking tube will not unlock the bolt enough to permit a human being of normal strength to pull it to the rear. That's alot of words but I think that I've got it about right. If I don't I am sure someone will correct me.

[M1 Tanker]

In a nutshall, the bolt carrier should not be resting on the cocking tube stop, there should be a small gap in there, as 97th sig said.

If it rest on the stop, it will slam into it when you fire it, destroying it.

If its too far away, its going to be really really hard to charge.

[roland3]

i see, thanks

[rustypirate]

One simple way to test the gap is to try and insert a sewing needle between the end of the cocking tube and the front of the charging handle support.

If it does not go in, you have too little gap, and if it goes in easy with no drag at all, then too much.

The key here is to get the needle at an angle so that it comes between the support and the end of the tube, rather than between the end of the tube and the charging handle itself.