I have read what is available on the conversions from springer to gas for Hatsan rifles, and thought this information would be of interest to share, as I received it yesterday. According to a sales person at PA, after an inquiry for said rifle about tuning prior to shipping out. "We can take the gun apart, clean it, polish the piston and regrease it for $40. Very soon, we will also start offering nitro pistons for that model as well."
"So, the best you can hope for is TRAIL NP XL performance levels !" And we know we can do better than that and be safe to boot !!!