FX Impact MK11 700mm barrel 25 cal. NSA slug question

Mine is currently running a cf lined slug a barrel. I have both the standard and heavy superior liners. I need to test the superior some more yet. I just put in a dual transfer port from Ernest Rowe. I had to drop my reg pressure down to 110-115 bar. At 125 bar I was slinging 26.8 gr nsa @ 1013 FPS maybe a touch faster off the top of my head. I’m currently shooting them at 960 FPS or so.

the issue for me is I cast my own slugs and haven’t been able to dial in my ammo just yet with either superior liner. They are way to heavily choked in my mind. My slug a is drilling holes at 30 yards with no issue. I also have my hammer spring way down as I want to be able to just flip my transfer port 180* and switch between slugs and pellets without messing with the tune. So far it has been working well.
 
If memory serves me, I’m shootings the nsa 33.5 in the same set up as op. Reg 130+, valve 4+, hammer close to max at 965 with good results. 
I have installed the heavy liner but haven’t shot much with it yet. The fx 26 hybrids in the same configuration as above are running at 1045 with excellent results, haven’t shot enough nsa’s but the few 33.5’s I did seem to shoot really well too.