GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: mschlee on January 21, 2018, 10:23:36 AM
-
posted this over on tag but wondering what folks here think.
been tuning and modifying what started as an .22 cal escape ss to get the best accuracy at 50yrds. so far the best i've achieved is with the current setup as an 18" tt .25 cal barrel, with a standard valve tank (not the original high flow valve which was too sporadic). shot strings velocity wise look really good (see below shot with polymags).
been testing variety of pellets and groups seem great for a few rounds then get some fliers and/or poi shift.
next up will be to limit frame flex and improved trigger.
question to experts here - i'm trying to achieve consistent, sub .75 inch groups at 50 yards, is that a reasonable expectation or most likely unobtainable?
thanks in advance
shot fps fpe
20 755 32.91
19 756 33
18 754 32.83
17 755 32.91
16 756 33
15 759 33.26
14 752 32.65
13 762 33.53
12 762 33.53
11 766 33.88
10 764 33.7
9 769 34.15
8 770 34.23
7 769 34.15
6 769 34.15
5 768 34.06
4 768 34.06
3 771 34.32
2 775 34.68
1 781 35.22
Average: 764 33.70
StdDev: 8
Min: 752
Max: 781
Spread: 29
-
I think that 3/4" groups at 50 yards is doable if you do you part .
-
thanks blacktalon. what is your experience with your talon? similar?
-
I only shoot out to 35 ish yards. But can hit beer caps just about every time. When I miss it is me. That is with the talon SS or the condor SS.
-
The only time I did 50 yard testing with my Condor 24" I was averaging 0.6", but got a best of 0.54" CTC.
I do not have any experience with the standard Talon valve, but I think you should have no problem getting 0.75" at 50yds, although your gun may require some tuning or work to achieve it. Your shot string looks pretty good so you are off to a good start.
Polymags are not known for good 50 yard accuracy. I have the same issue with Polymags in all my Condors, especially my .22 Condor. In my 30yd testing 3 or 4 would be touching, and then what seemed like a flier. Domed pellets from JSB and H&N should give you the best performance at 50 yards. Some Talons/Condors also prefer the Baracuda/Kodiak, but they all do well with JSB 15.89 or 18.1gr (and JSB King in .25).
Sometimes fliers can occur when 1 or both of the breach o-rings need to be replaced, and always when the tophat screws have come loose. If you have more than 600 shots on the gun I would replace the breach o-rings, and check the tophat screws every other fill.
Harry
-
thanks harry. tried a bunch of hn pellets (barracuda, hunter extreme,crow magnum, etc.) cause i really wanted a decent hollowpoint to hit the squirrels with. just ordered some jsb and jsb heavies (the 25gr, 33 gr, and 33gr mkii) to run through next weekend and see what happens. if that does not do the trick, i'm gonna either:
1- send it off to someone like mac1 or talontunes for a tune
2 - sell it and pick up an fx wildcat
hopefully the pellets work out and i'm good to go.
thanks for the info.
-
OK I didn't think you had a .25 but now that I see the kinetic energy in your strings, I realize you have a .25. I personally would not shoot .25 with a standard tank. The problem at 50yds with heavier pellets is that going from 780fps down to 750fps will change the POI, and could be the "fliers" you mentioned. I would not have ordered the JSB 33.9gr I had your setup with a standard tank. They are going to be in the mid-600 range. That is not a good .25 setup. The 25.4gr JSB Kings will work out better for you, but I still would not recommend that setup unless you can increase the power by at least 50fps.
You should really be using the hi-flow/Condor tank, especially for hunting at 50 yards, and use the rubber o-ring "trick" on the tophat to keep velocities down like many people have done including myself. The o-ring behind the tophat made one of my .25 Condors extremely consistent and efficient as if it has a regulator, on top of reducing the velocity by well over 100fps. Without the o-ring it was shooting all over the place after a few good shots and the SD and ES were all over the place. With the o-ring I was able to tune it further by adjusting the tophat with a low starting fill of 2,300psi and ending at 1,950 for 25 consistent shots with a 9 fps max. spread, or 30 shots with an ~18fps spread. This setup shoots the first 25 JSB Kings at 940-950fps very accurately, and my tanks last a lot longer not having to fill to higher pressures.
Domed pellets will give you the best accuracy at 50, and the JSB King 25.4 will shoot a little better than the 33.9 if you still have a Lothar Walther barrel.
Good luck,
Harry