doc3

Sporter Not Performing.
OPERATING: Lee & PAPABEAR

A new APS2 MK2 SPORTER had been fitted with FIRST FACTORY piston, spring guide and 492fps spring. However, it was chronographing @ 430fps and was proving inconsistant. The gun was put in for an APS SERVICE and SETUP.

Cycling the BOLT, it was apparant that the Action did not cycle as smoothly as it should. The 2 bolts that hold the action to the furniture, had been overtightened (apparantly a common fault). This had resulted in the TRIGGER GUARD moving and the Bolt therefore touching the CYLINDER underneath. This had resulted in friction that had shaved metal from the CYLINDER. The rear Stock Bolt was filed down by a couple of mil to avoid this contact and compensate for the now, reccessed TRIGGER GUARD. The Action was still not right: so incorrect GREASING was the Diagnosis.

First off, the BARREL was removed and examined. The HOP unit had jammed up and the �seal� was not seating correctly. This can easily happen, so the user must learn to tackle this. However the 6.05mm barrel was full of grease and metal shavings (from the CYLINDER). The barrel was cleaned and polished, before the well lubricted HOP unit was reassembeld.

The CYLINDER head was slightly damaged, externally. Although PAPABEAR managed to remove it, without further stress. Using a SPECIALIST TOOL. Inside the unit, there was an excess of GREASE. Again, the grease was not the correct type for the job. Mixed into it, were filings from the original fault. The unit was cleaned up and degreased before applying specialist GREASE for compression chambers.

The unit was reassmbled. Lee put 200+ 0.20g pellets through the gun. before stripping the BARREL again. This was to run in the parts and remove excess grease. This had been blasted down the barrel, so again the HOP and 6.05mm tube were cleaned up.

SETUP
Moving the scope backwards, to get a more natural & comfortable eye relief. We assessed the firing position. Now your eye was in the right location, as soon as you shouldered the gun.
The Gun cycled smoothly now. No friction on the bolt. When fired it sounded like a dream (no vibration or �CRACK�). Full range was now being achieved, with a steady tweaking of the HOP UNIT.

On the chronograph, it registered an average of 474fps.