Okay...
Decided to give the gun a "once-over"with an objective to improve efficiency and not FPS.
How to open the IHP up has been well catalogued - hence am not going to repeat it. Apon opening we found the spring and the piston and the innards had rust on it. The gun was also extremely greasy in places! Both the piston and the chamber was horribly scored - so much so that the OE synthetic washer had already started fraying at the edges (must have seen a max of 50 shots till then).
After much debate, I decided not to spend too much money without guarantee of tangible results. Hence we decided to change only ONE thing - the SEAL.
The chamber was horribly scored. Apparently that is how the new guns look! We had the chamber and the piston polished on a lathe - NOT mirror finish - you need the micro grooves for retaining the lubricant. Next I got myself an Jim Macari Apex Seal. The adapter was made locally. The spring was given a thorough cleaning. The OE Spring guide was totally LOOSE. hence had a new mild steel one fabricated. Wanted to use a top hat but I did not want to cut the spring - hence left that.
Now the assembly...
We first smeared a little Jim MAcari's Moly on the outside side surface of the Seal and the top and bottom of the piston where it comes in contact with the chamber. We then introduced the piston carefully into the chamber and tested it. HOW? We closed the discharge port with a finger and tried to pull the piston back.. if you find the piston refusing to move beyond a point, and moving back when let go - that means vacuum is being generated- the tolerances are good and the seal is doing its job!
We then smeared a little Moly on the spring guide (very little mind you - not the 'greasing' we are used to
). and placed the spring on it. we then dabbed the outside of the spring with Jim Maccari's Heavy Tar - again very very lightly - just enough to coat the surface. Some more Moly was dabbed on the lever cocking joint, the trigger joint and the actual lever and the barrel joint. We then put the whole thing back together. We also put in a synthetic washer in place of the leather breech seal. (I am not too happy with the fit and finish of that but its doing its job - absolutely zero air leakage.)
Despite being as careful as we could, the first test shot dieseled and how!
We literally had sparks flying out of the muzzle! But it settled down immediately thereafter.
Took it to the range - shot off a round - and everyone jumped! The Solid THWAK the pellet made as it struck the deflector meant the power was in a different league. We zeroed the gun and fired off a few shots (pellets were the MasterShot Flatheads). I have never seen a target with better 'cuts' - nice clean round holes... no tearing, snagging etc.
Met up with TenX's. We shot off a round or two into a tree at about 8-10 mtrs and the pellet clean buried itself over a cm deep! When fired into the ground the pellet totally and completely disintegrated. He commented that in addition to the power being great, he found both the trigger and recoil excellent too! Cant ask for anything more at this price! Am more than happy so far!
Wanted to take some pictures but the whole things happened in a haphazard way spread over three weeks - hence could not catalogue it pictorially. Will be taking the gun to the range next Sunday for some hand held and bench rested shots - to check grouping. Will try and post some pictures. Need to try and see if I can get access to a chrony as well!
The only issue left with the gun is it takes quite some effort to load a pellet into the barrel. Fingernail only! So after about a couple of dozen shots your fingertips hurt as hell! Wondering if I should have the barrel end bevelled a little - or leave it well alone!
I have to thank TenX and PKJeetesh for their inputs. Could not have done without them! Thank you guys.. I owe you one!
Next project is the complete refurbishing of a Circa 1984 IHP .22 (the one with the peep sight). This one will get the complete Jim Maccari treatment - springs and all! Am looking forward to it!
