Daisy 499B shot tube
1. Use only finger tension to tighten the shot tube into the gun. Over tightening will result in breaking the abutment plug loose inside the compression chamber. A loose abutment plug ruins the guns accuracy and is very difficult to repair.
2. The shot tube should fit against the barrel shroud and have zero side to side movement. Some guns need to have the shot shortened. This problem is common on older guns. To shorten the shot tube, metal must be removed from the threaded end of the tube.
3. The barrel shroud is not welded and tends to spread. This is good and bad in that the slight spreading helps snug the assembly into correct tension, but it can get loose. The rule book allows a single layer of non-reflective tape around the barrel, that can be used to prevent a loose seam.
4. The shot tube assembly is 3 parts. Do not tighten the aluminum nut with a wrench or the plastic shroud will crack. The plastic shroud is a common breakage issue, a sudden lose of accuracy is often a broken shot tube shroud.
5. Some shot tubes are just plain bad and will not group in the 9 ring.
6. When the shot tube is correctly installed, it should be secured in place with a single layer of non-reflective tape.
7. Clean the shot tube by removing it from the gun. Cleaning while in the gun can dislodge the tiny magnet, which is glued in the abutment plug.

Plunger tube

1. The plunger spring assembly is removed with the use of a special tool that pushed the sprung forward so the spring anchor can be withdrawn from the slot in the top of the barrel shroud. The butt stock, trigger assembly and cocking lever must be removed so the plunger can be pulled out the back of the gun.
2. Use a 12 ga. Shotgun cleaning brush to clean dirty oil and grease from the gun.
3. The 499B can have rough edges inside the compression chamber. When removing and installing the plunger assembly look for damage to the plunger head caused by sharp edges.
4. Replace the head as needed. The current white plunger heads seem pretty goods, if you find a black plastic head, it should be replaced.
5. Lightly lubricate the compression chamber, remove excess with a dry patch.
6. Plunger springs can weaken over time and may need to be replaced.
7. Best accuracy is gained by polishing the compression chamber to remove the paint and even out high/low spots or rough areas.

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