Hi Guys, does anyone have any experience shooting jsb 18 gr at 950 fps? Im shooting them now in my JKHAN ILUDA N400 and it seems to be pretty acurate at 40m 45m. It has a LW barrel. Waitung for the wind to die down to get some more distance.
Yeah my jkhan was moving them at 1200 fps before nick from ss airguns got hold of it and tuned it into a unregulated sweet spot of 50 shots at 949to 954 fps. Its very very acurate at 45m so hopefulle tomorrow i can push it to the 80 90 100m mark and stil be that accurate. It seems the korean rifles like the speed a bit higher. But as im reading the 920 fps seems to be cutt off point for most guys. But if im getting that same accuracy at longer distances im not bringing it down. So....my question from guys with different guns....whats the first hand experiences with jsb 18 gr at 950 fps. I read a guy saying that setup in his sumatra is deadly . But good to hear you guys are finding the speed ok. If im making any sense here
On this forum you have to be very careful when talking about your Sumatra (ugly Betty) people here do NOT like them. But yes 18.13 JSB's are the preferred pallet through my Ugly Betty when the power is tuned down. It seams to me that they can handle the extra speed. My daystate huntsman running at close toe 40 fpe also like the 18.13 JSB's.
Good to hear. Its hard figuring all tgis out with no chrony. So its next on the list. I reckon all the jkhan rifles will have the same LW barrels? Ive been playing around but at one moment i get almost pellet in pellet and the suddebly it starts going to about a 50c size maybe. And the gun is on a bench solid. My sweet spot shifted a bit but seems to be from 190 bar to 150 br and about 40 shots.....seems oraait.
In my Dawson, 18gr did best ................ "read, same accuracy" @
860 ft/sec ...... Why "waste" the big 5.5 on such a low velocity .....
930 ft/sec ...... Happy medium .....
985 ft/sec ...... Air hungry (relative) .... needed a big volume silencer
In the end I settled on 930 ft/sec ..... best of both worlds.
For what I see, "on my rifles", with the 18's the best performance is from 920 to 960fps, above that I use heavier pellets to balance out between speed and pellet weight.
I wouldn't tune the Jkhan lower than that, in fact I will try to push it up to around 980fps to see how it goes, above that, I doubt it if it will be better.
Thats the thing....to see what works in the gun. So i have to put some time in....as i have done. I put about 3200 jsb 18gr through it in 2 weeks. But there is no way to play with the power and identify the sweetspot without a chrony so i ordered one and it will be here tomorrow. I think the fps in my sweet spot still goes up and down toooo much now and then. I will have great groups and then a a few starts moving around. I have a harder valve spring in now so my sweetspot should stay up in the higher preasures but if i get it to group consistantly at 955 fps ill keep it there otherwise its coming down to 930 920 because it runs pretty accurate there as ive seen on the first chrony session a week ago. So hopefully tomorrow i can get it sorted. Ill post some groupings at 40m and 50m if weather permits. I mean.....what is a good grouping at that distances? Like i said i get tight groups of about the size of a 20 cent piece now and then but then it starts jumping around a vit and that can only be pellet speed going up or down.
Yeah it seems the jkhan and sumatras handle the 18 gr better at high speed than most. No way um going to be shooting at sub 900 fps. So 920 will be my limmit. But ill jave to see where my preasure stabilises and levels out for a good amount of usable shots....the gun has been tuned but its been a mission. How many consistant usable shots do you get from you jkhan at 960fps....? At 955 fps i get about 40 maybe 50 but not every single one will grouo as i would like.