The last one I had I used a ptfe piston head from tr robb I also used one of his springs it sorted the power problem that I had no probs
Has any one had problems with Airsporter/Mercury low power using none genuine alloy piston heads. I have had an Airsporter apart 4 time replaced the nylon type head that was sized with a alloy head , new Oring buffer washer and spring . .22cal and its only doing 8 ft lbs , fitted a Titan XS spring and use a genuine BSA O ring still the same. Also i have rebuilt a .22cal Mercury new alloy head , seals spring and barrel seal 9.5 ft lbs ?.
.22 Venom Mach 1 (FAC) 6-25x56 Millett.
.22 Venom Mach 2 Thumbhole 6.5-20x40 Leupold EFR.
.22 Venom Mach 2 Sporter 4-12x40 Leupold.
.177 Venom Vantage 4-16x50.
.177 Venom Daystate 8-32x56 AGS.
.22 Venom Datstate 4-16x56 AGS.
.22 Webley Venom FX2000 6-18x40 Busnel Legend.
.177 Titan MPT by Steve Pope 6-24x40 Tasco.
.177 Pro-Sport 4-16x50.
.22 Webley FX2000 3-9x33 Leupold EFR.
.177 Logan Solo 4-16x50.
.22 HW90 (spring powered) 4-16x50
.22 Gamo Stutzen.
.177 Walther lever action.
The last one I had I used a ptfe piston head from tr robb I also used one of his springs it sorted the power problem that I had no probs
I've got an airsporter I've been trying to get right for a couple of years now and am no nearer than when I started. It's had various heads, several o rings, a custom head with Diana seal, various different springs, guides, piston sleeves, longstoked, etc etc. Every possible mod done and no different at the end of it all. Match abandoned. On the other hand, I have a Mercury which I have only cleaned and lubed. Sweet as a nut and doing 10.75 fpe.
Is the cylinder bore not parralel or could it have bulged due to detonation leading to poor sealing????
Or is the air getting round the tap instead of through it?
WANTED: Next weeks winning lottery numbers :-)
leaking someplace... o-ring heads need a very true cylinder to seal, far less forgiving than a lipped parachute style - as above maybe the cyldinder is dented / bulged / scored
Always looking for any cheap, interesting, knackered "project" guns. Thanks, JB.
The tap seems fine. It does point to a problem with the cylinder. Or the transfer port?
8ftlbs is common in later mark .22 Airsporters the MK1 and MK2 are typically better powered.
Would have thought around the 500fps to be expected, not many British guns made much more. It's more important that the cock and firing cycle is smooth and twang free and it is consistent. I've tried everything to get my Webley hawk mk2 to make 10fpe apart from machine the piston and the best I could get is 8fpe, but it's now virtually recoil free smooth to fire and very accurate. It's only going to be used for plinking so power isn't priority
Mercury's should make power easier than an airsporter due to the loading tap. I found that how far the pellet drops into the tap makes a significant difference to the power. One of mine leaked so badly that I got the plug machined to add o rings which cured the problem.
The Mercury should make 10 ftlbs plus if everything is OK.
Plinkerer and Tinkerer
Did you de-burr the cocking slot!