how many uses for paperclips do you know.
Oh good lord. First off, you don't lock the bolt forward. You lock it BACK so that you can inspect the chamber and insert a fresh magazine for chambering. You lock it BACK with the BOLT STOP, which is that little rocker switch on the left hand side of the gun, right at the dividing line between the upper and lower receiver, above the magazine well. To lock the bolt back on an empty firearm with no magazine inserted: 1) Place left thumb on bottom portion of rocker switch and apply tension against the spring. 2) Pull charging handle fully to the rear, until you feel the bolt carrier cam its way past the bolt stop you will feel this under your thumb on the rocker switch. 3) The charging handle will now be free-moving, no longer under spring tension from the bolt carrier. Go ahead and slide it back to its resting position. 4) If the weapon functions properly, you can now release the rocker switch and the bolt will remain held open. The charging handle has an interference relationship with the bolt carrier group, meaning that it is in front of it from the perspective of the buffer spring. In layman's terms, you can only PULL the bolt with the charging handle, you CANNOT PUSH it. (hence the reason for the addition of the silly Forward Assist). Once the bolt is locked open, you can slide the charging handle forward freely, or just leave it be, though it looks a little silly and could expose the thin aluminum charging handle to damage from lateral force. Your choice. Once the bolt is back, the charging handle is free-moving. This is part of the design. I don't really understand your question, and it kinda frightens me that you might not, either.
Take unit to audio/video repair shop.
an oil burner should be serviced annually. gas boiler really do not produce the soot ash and do not need frequent service. some circulator pumps on them could be given a couple drops of lubricating oil.when burning gas, be sure you have a carbon monoxide detector that works, as a chimney blockage would pose a potentially life threatening hazard.
