Hi Guys,
Compiled a bunch of info from various forums specific to improving the power/shot cycle of an LGU. This is what I did based on that info:
Should apply to both .22 and .177. My gun is a .177.
1. Check compression tube transfer port diameter. Open to 3.5mm. This will improve flow and reduce/eliminate piston bounce and aid spring life.
a. some folks have experience a loss of power over time due to this restriction(spring starts to tire out).
2. Cut rear spring guide flush with trigger housing and install HW77 25mm Vortek PG2 14ft/lb kit with vac seal (black with moly). Fits no problem and easy to cock.
a. You could also do this with various other springs as well. I understand a D34 spring will fit the factory guide and provide a bump but I like the Vortek PG2 units.
3. Enjoy a more powerful and consistent LGU with a quick shot cycle.
Results:
6.64gr H and N Barracuda greens = 1000fps/14.75 ft/lbs (lead free)
8.1gr Air Venturi = 900fps/14.5ft/lbs
8.2gr RWS Meisters = 890fps/14.43 ft/lbs (lead)
8.4gr JSB Exact Premium = 870fps/14.1ft/lbs
8.8gr H and N FTT Power = 840fps/13.79 ft/lbs (copper coated)
10.6gr H and N Barracuda Power = 740fps/12.95 ft/lbs (copper coated)
Overall gain was around 90-100fps across the board and 2-3ft/lbs. Sweet spot is in the 7-8gr pellet range but the heavier pellets should have a better BC with the increase in velocity. Still breaking in too. Now that winter is in full effect I am mainly shooting "non-lead" or copper coated indoors so the 6.64/8.8/10.6 will probably be my go to till I can get outdoors again.
If you want a sub 12ft/lb gun with improved shot cycle I would still open the port and look at reducing preload on the factory spring. Lots of good info out there on the LGU power plant and how to improve an already great shooter. This is by no means the end all as there are certainly other options and combos out there but I hope this helps provide a good overview of what you can do with off the shelf components.
NOTE: The LGU is super easy to take down and work on but as always use caution and make sure to take your time.
Regards,
DT
Updated with a few more pellets on 1/5/18
Compiled a bunch of info from various forums specific to improving the power/shot cycle of an LGU. This is what I did based on that info:
Should apply to both .22 and .177. My gun is a .177.
1. Check compression tube transfer port diameter. Open to 3.5mm. This will improve flow and reduce/eliminate piston bounce and aid spring life.
a. some folks have experience a loss of power over time due to this restriction(spring starts to tire out).
2. Cut rear spring guide flush with trigger housing and install HW77 25mm Vortek PG2 14ft/lb kit with vac seal (black with moly). Fits no problem and easy to cock.
a. You could also do this with various other springs as well. I understand a D34 spring will fit the factory guide and provide a bump but I like the Vortek PG2 units.
3. Enjoy a more powerful and consistent LGU with a quick shot cycle.
Results:
6.64gr H and N Barracuda greens = 1000fps/14.75 ft/lbs (lead free)
8.1gr Air Venturi = 900fps/14.5ft/lbs
8.2gr RWS Meisters = 890fps/14.43 ft/lbs (lead)
8.4gr JSB Exact Premium = 870fps/14.1ft/lbs
8.8gr H and N FTT Power = 840fps/13.79 ft/lbs (copper coated)
10.6gr H and N Barracuda Power = 740fps/12.95 ft/lbs (copper coated)
Overall gain was around 90-100fps across the board and 2-3ft/lbs. Sweet spot is in the 7-8gr pellet range but the heavier pellets should have a better BC with the increase in velocity. Still breaking in too. Now that winter is in full effect I am mainly shooting "non-lead" or copper coated indoors so the 6.64/8.8/10.6 will probably be my go to till I can get outdoors again.
If you want a sub 12ft/lb gun with improved shot cycle I would still open the port and look at reducing preload on the factory spring. Lots of good info out there on the LGU power plant and how to improve an already great shooter. This is by no means the end all as there are certainly other options and combos out there but I hope this helps provide a good overview of what you can do with off the shelf components.
NOTE: The LGU is super easy to take down and work on but as always use caution and make sure to take your time.
Regards,
DT
Updated with a few more pellets on 1/5/18