Nothing revolutionary here but the info might be useful to others and I spent a lot of time testing and optimizing…
My L2 .177 had been doing duty with a 500mm FX liner - see my old “Ratflex” thread for info. With Fall approaching, and then XC skiing, I felt a hankering to cut it down to the most compact form with a 250mm AP polygon barrel. The safe-to-transport and rock solid folding backpack carbine. IMHO, that’s its proper niche. The only downside is lack of power. Last time I used it, with stock 1.2mm jets and reg at 140bar, it would shoot JSB 10.34s at 885fps with great accuracy. However, speed was down at 835fps with Zan 10 grain slugs, and I love those pills but that not enough juice for my comfort.
Given that my REPR reg has been really solid, I took a chance on pushing up the pressure and then fine tuning with jets to really optimize the efficiency and accuracy with the magic little slugs, which I knew shot well from this poly barrel, accuracy wise. Tuning was done with a very accurate (validated) digital gauge, so if you want to run my tune, the numbers are good. The optimizing and testing was done over several weeks and the reg, accuracy and ES are very solid, with a first shot drop of only 8fps.
Dog bone and collar are still inside and unmodified. At the end of the process, we’re at a reg pressure of 162bar with 2 x 10mm jets. The 10 grain Zans are flying at 908fps average for around 19fpe. 10.34 pellets are zinging out at 960fps! I won’t get into showing targets but the accuracy with the Zans is very solid, tested out to 80 yards. As usual, it’s all about the trigger protocol. Anyway, I think it’s pretty remarkable to get this tiny guy running slugs at close to 20fpe. Those little pills have the penetrating force of a 32fpe .22 and expand really well. Sure, the GK1 can blow it away, but this is 177 regulated (with 6fps spread, after that first shot), and while it’s GK1 size folded, it expands into a proper rifle that shoulders very well (that’s coming from a biathlon competitor).
There’s no other mods on this baby, aside from a thin delrin seal between the shroud and action, which really helps with noise from the normally leaky shroud. The shroud hosts the STO insert which is a big improvement over stock. With the trigger well tuned, this is a very stealthy rig. The neighbors might wonder why youre opening so many cans of soda!
The optic is the Optisan CP 3-12, which has great glass, the not-too-little or too much Xmas tree reticle, nice defined clicks and focuses down to 8 yards. A great low profile option for this little pew pew, although I’m sorely tempted to pop on a Zulus! There’s no clashing with folding, using the one piece Optisan mount. I’m a fan of the single speedloaders with neo magnets holding them on a mount. The tiny analog reg gauge is a post tuning substitution. Really just there to let me know if the POM seal gives it up…
My L2 .177 had been doing duty with a 500mm FX liner - see my old “Ratflex” thread for info. With Fall approaching, and then XC skiing, I felt a hankering to cut it down to the most compact form with a 250mm AP polygon barrel. The safe-to-transport and rock solid folding backpack carbine. IMHO, that’s its proper niche. The only downside is lack of power. Last time I used it, with stock 1.2mm jets and reg at 140bar, it would shoot JSB 10.34s at 885fps with great accuracy. However, speed was down at 835fps with Zan 10 grain slugs, and I love those pills but that not enough juice for my comfort.
Given that my REPR reg has been really solid, I took a chance on pushing up the pressure and then fine tuning with jets to really optimize the efficiency and accuracy with the magic little slugs, which I knew shot well from this poly barrel, accuracy wise. Tuning was done with a very accurate (validated) digital gauge, so if you want to run my tune, the numbers are good. The optimizing and testing was done over several weeks and the reg, accuracy and ES are very solid, with a first shot drop of only 8fps.
Dog bone and collar are still inside and unmodified. At the end of the process, we’re at a reg pressure of 162bar with 2 x 10mm jets. The 10 grain Zans are flying at 908fps average for around 19fpe. 10.34 pellets are zinging out at 960fps! I won’t get into showing targets but the accuracy with the Zans is very solid, tested out to 80 yards. As usual, it’s all about the trigger protocol. Anyway, I think it’s pretty remarkable to get this tiny guy running slugs at close to 20fpe. Those little pills have the penetrating force of a 32fpe .22 and expand really well. Sure, the GK1 can blow it away, but this is 177 regulated (with 6fps spread, after that first shot), and while it’s GK1 size folded, it expands into a proper rifle that shoulders very well (that’s coming from a biathlon competitor).
There’s no other mods on this baby, aside from a thin delrin seal between the shroud and action, which really helps with noise from the normally leaky shroud. The shroud hosts the STO insert which is a big improvement over stock. With the trigger well tuned, this is a very stealthy rig. The neighbors might wonder why youre opening so many cans of soda!
The optic is the Optisan CP 3-12, which has great glass, the not-too-little or too much Xmas tree reticle, nice defined clicks and focuses down to 8 yards. A great low profile option for this little pew pew, although I’m sorely tempted to pop on a Zulus! There’s no clashing with folding, using the one piece Optisan mount. I’m a fan of the single speedloaders with neo magnets holding them on a mount. The tiny analog reg gauge is a post tuning substitution. Really just there to let me know if the POM seal gives it up…
