Done wasting time and air on my Urban

[toddbrat]

I think I have it right where I want it. Had some time over the last couple of days to play with the power adjuster more, I had it set to average about 730fps over 40 shots with a fill to 2800psi. I wanted to see how low I could go and maintain accuracy to my far target of 63 yards. My goal is to use this to better simulate long range PB shooting at home. I ended up backing the power all the way down and was very surprised at what I found.

Using ChronoConnect, starting at 2800 and going down to about 1200psi, I can get almost 50 "decent" shots with an average of about 660fps or ~14FPE. The first 20 where the worst, spot on when zeroed to 29, opening up at 50 and all over the paper at 63. I checked my energy with ChairGun and measuring drop between distances I feel pretty good about the energy. The first 20 shots where low, barely cracking 12fpe. I'm using H&N FTT in 5.53 head size. After those 20, things smoothed out really well. Wind was up pretty heavy yesterday while testing this so I took all results with a grain of salt. Today was a different story. Sunny with just a hint of wind, but gusty at times. I backed the fill down to 2000PSI, the point it seemed to like yesterday. Today was a new issue, however. I have a cheap 6-24 scope and not sure if it was the cold or me but I couldn't get the parallax out, even though yesterday it was fine. Anyway, backed the power down to 6x and took aim at the 1/2" bullseye. The pics are the full 30 shots, first in 5, then 10, 20 and 30. I need to try the last group of 10 again as it really opened up but with 50 people coming for Thanksgiving tomorrow had to help the wife. 

I have my Urban now set for just over 14fpe, getting 30 shots from 2000psi down to about 1100-1200. Based on Lloyd's Sikes calculator, that gives me 114 fills from my SCUBA tank. I'm extremely happy with the results, especially since I can use a very low fill pressure and maintain great accuracy for my needs.

[oldpro]

 I dont think you have a gun problem you have a ballistics problem(I think). At those speeds at that distance even the slightest breeze will toss the pellet all over the place so before I gave up I would try two things. First move the target into 35 yards and try again and if you have same groupings you have a problem or turn power up to 850ish and try at current target and try again also try the JSB and Crosman pellets to make sure its not the pellet.

[toddbrat]

Thanks, Travis. The title was a bit tongue in cheek, I've been trying different power levels to hit 3 main goals: keep the accuracy that I've seen at higher power,  use the least amount of air possible and get as many "good" shots as i can. I use ChronoConnect, Chairgun and a ruler to get "close enough" data and then adjust from there. I will mainly be shooting small targets with low power as far as possible to better simulate a PB at 300+ yards. The wind drift is an added bonus, I didn't dope it today as I was looking for vertical stringing more than horizontal.

Btw, great work on the new valves, will they work in a .177 Maximus?

[Ribbonstone]

Comes a time, even when you enter a tune-session without a clear goal, to call it "good 'nuff" and leave it the *(&^ alone.  You've reached that point.


OK...at least for now. May come a time when you want "more".  Either more power (and fewer shots per fill) or more shots (less power per shot).

It's both the blessing and the curse of PCP's: can easily change the out put results

[toddbrat]

That is exactly where I am. Plan on adding some better glass and that's it, at least for now  .

The next challenge is going to be convincing the wife that I really do need a compressor.

[toddbrat]

Had perfect weather and the time to enjoy it yesterday so decided to see if I could tighten up the 30 shot group. I did my best to hold the same aim point at 6x, but the cheap 6-24 from Amazon is just too thick for me, thinking of adding a UTG or Hawke after the first of the year. Kept the same fill pressure of 2k psi and shot down to about 1100-1200, 30 pretty consistent shots. It may not win any awards but I sure am happy with it. The shots on the upper left where all me, for some reason I had tightened my grip and took me a few shots to realize it. The one low shot was the first shot, right after topping it up to 2000psi.

[toddbrat]

Another price drop. Down to $198 on Amazon (temp. out of stock) and at Walmart.com. Ordered one for my son for his birthday in March. At this price, it is definitely the "entry-level" PCP to beat.

[CraigH]

Very difficult, if not impossible, to disagree.   But all have certain charms, and more likely regrettable characteristics.