I really don’t wanna shoot that heavy of a slug, the guns just as loud as my 22lr at that point and the shot count is terrible. I wanna keep it down low for good shot count and cheaper ammo.
Upvote 0
FX Do I need a slug power kit?
- Thread starter spikex41
- Start date
If you are shooting lighter slugs you probably dont need to use the power kit. I was able to shoot .25 fx hybrids to 1,000 fps with a reg setting around 135 - 140 bar with the standard hammer and valve spring.
If you are going for the lighter slugs I would try FX hybrids, H&N slug hollow point II maybe the lighter zans and lighter weight NSA slugs. What twist slug liner do you have? I have the 16 twist but I wonder if the 18 twist would have worked better with the lighter weight stuff.
Upvote 0
I was shooting these yesterday, didn’t finish tuning I got it to about 1” group at 50y for 15 shot group. Get the odd one that’s like almost 1/4” for 5 shot but if I fired a 10-15 shot group they were more like 1” groups. Everyone gets lucky now and then haha. But I was only 125 bar, my fps plateau was 970 fps and my hammer is as 4.6 ish, almost maxed out. I don’t feel like the gun will do much faster without the heavier hammer now. I only have another like 250 or 300 slugs so I don’t have enough to actually finish going thru the tuning but figured I would just waste these up for now and see the max reg pressure I can work with without the heavy hammer.
Upvote 0
I have the superior heavy liner so it’s 18 twist for .25 cal. Then the factory superior liner is 24 twist but it’s choked for pellets. I may try both as I’m told lighter the slug the less twist it needs. Not sure about the choked part thow but we’ll see I’ll play around when the slugs come in. i Really don’t want to shoot fx hybrids bc there not cheap lol I will if I have to but will try the cheaper nsa, then maybe the Zans and H&N before I go to the fx hybrids.
Upvote 0
Well my slugs come in today 26.8gr nsa, got out to test quick after work went thru a whole box already, left the reg at 128 bar where It was already sitting just to see where It ended up. My peak speed was 1075 fps, I then tried it every 10-15 fps down to 900 with my best group being about 2”. Changed barrel and tried it with the regular stx barrel instead of superior and went back to 1060 fps and tried all the speeds down to 920 and shot my first 1/2 inch group. Tuned it down to 910-915 seems to stay around 1 to half inch groups. I stopped at this point and I’m going to wait for a no wind day (currently up to 30 Km/h wind gusts) and see if it’s still doing ok or if the wind happened to push them all together.
so from this point I assume bc I’m close to 15% off my peak speed I need to lower the reg till my fps is closer to 960-970 fps at the peak so I’m at the 5% from the peak spot when I set it to 910 to try accuracy testing again. Hopefully it works out with the pellet liner, I really don’t have enough ammo to test 2 barrels I do not think, I only got 5 boxes and used 1 already haha well see if I run out.
so from this point I assume bc I’m close to 15% off my peak speed I need to lower the reg till my fps is closer to 960-970 fps at the peak so I’m at the 5% from the peak spot when I set it to 910 to try accuracy testing again. Hopefully it works out with the pellet liner, I really don’t have enough ammo to test 2 barrels I do not think, I only got 5 boxes and used 1 already haha well see if I run out.
Upvote 0
I am currently in a similar situation. I built a little longer barrel to hopefully balance slug and pellet shooting on the same reg setting. I found the accuracy I was looking for with slugs on the high end of the tuning parameters that I’m comfortable with. I would be more comfortable with a little higher reg setting and a little less valve dwell to hit the 930fps..Right now the valve is almost wide open and I’m not real far below my peak reg speed for 930fps but the gun shoots great. So now it’s the debate. I’ve played this game before. It doesn’t always work out. Not all 930fps are created equal because of air delivery. What we think will be more efficient winds up making the slug mad.
Upvote 0
Well I got out again today with hardly no wind, my groups were back to 2” when I went out. I played around some, lowered my reg to 100 bar and my peak was around 1000 fps I tried both barrels down to 890 fps from about 970 nothing good, upped my reg to 110 and shot from 890-970 saw some good results around 890-910 with the pellet barrel. Swapped to the slug barrel and tried that from 890-980 and saw really good groups around 950-960 fps. I shot a few 1“ groups with 10 rounds, the gun was seeming to settle around .5“ groups after 20 rounds. so I packed up to go test at 100 yards and I noticed I was down to like 90 bar I fell off the reg lol so I don’t know how well it will do, maybe 90-95 bar is the sweet spot? I went to fill up and of course my luck the motor shaft snapped on my vevor air compressor so I had to go home and fill with my other one. Will have to try get out to resume testing another day. I hope it shoots good when I test it but if not maybe I’ll lower my reg to 90 and work my way up from there. Fingers crossed we’re getting closer haha.
Upvote 0
Got out and played around some more and got it shooting pretty damn good with the stx liner at 50 yards. Shot 10 shots with the 22lr to compare to and it’s pretty close to the same, hard to be sure as I have a 15-20km wind from behind but I will do further testing weather permitting. I’m really hoping my POI shift isn’t to bad from refilling the gun or when I take it out next, I notice the poi shift with slugs to be quite dramatic so far like almost a full inch off sometimes at 50 yards.
Upvote 0