More tuning fun I wanted to get rid of that climbing fps from about 165 bar down.
Here is how I went about that:
- brought my "low pulse length" from 1360 to 1330microseconds (took a little thinking for me to logic through this one, smaller # means a shorter blip of time, so less air and theoretically lower fps)
- filled the gun to 168 bar (I'm really liking the EXACT pressure supplied on the screen, kinda cool to watch it come down a few bar as a fresh, even intentionally slowly filled, fill cools off)
- shot a couple shots, with these results: 809.4, 823, 826.6, 819.8, 821.1, 821.4
- those shots being higher fps than desired made me realize I would need to bring down the "mid pulse length" as well
- changed "mid pulse length" from 1560-1545
- gun now at 166 bar from first couple shots
- first shot after mid pulse adjustment = 780fps "*$%&%$&, &$#&$, $&#%" I think to myself, and then remember that the first shot is low after any adjustments to the programming
- next shots = 810.8, 815.2, 811.6, 807.2, 808.7, etc. That's more like it! (remember goal is 815ish fps with 13.43gr JSB for just under 20fpe)
I went ahead and shot a string down to 110 bar. This is what that looked like.
I reported earlier today that I had an ES of 14. I was wrong. I had just skimmed down through my notes, finding high and low. Excel did a better job than my eyes when I ran MIN and MAX formulas after getting the data input.
Thoughts before moving on These numbers are starting to look quite promising, at least for FT! SD is quite good, only a couple shots are over the goal fps, and ALL of the shots are under the 2% variance in chronograph results granted by AAFTA rule book. So, I'm fully legal, and have a nice long shot string. I could just shoot from 165-110bar and have plenty of shots for a 2 day match, including some sighters prior to the match.
That brings up an interesting point. Just because a gun is capable of filling to 250 bar does not mean it needs to be filled that high. Lloyd Sikes online PCP fill calculator shows that somebody with a good ole SCUBA tank with a max fill of 207 bar (3000 psi) would be able to fill the RW to 165 bar (2393psi), shoot 144, 19.7fpe (Field Target legal) shots down to 110 bar (1595psi) and then get a complete refill back up to 165, a full 17 or 18 times. At 144 shots per fill, we're talking about 2448 shots, or about 5 tins of pellets. And there's still additional partial fills. I'm just making the point here, that a 4500psi SCBA is not always necessary for pcps, even high end ones like the RW.
The high, mid, and low pulse lengths only kinda coincide with the high, mid, and low pressure points. It seems like they overlap, or the CPU is constantly making adjustments. What I mean is that the low pulse length seems to kick in and possibly overlap with the mid pulse length, somewhere between the low and mid pressure point settings, in regards to the bottle pressure.
With what I think I know about the programming of the RW now, I'd stick my neck out to suggest that Daystate intends for High to be used with something like 250-200bar and then refilled and shot again. The "low pressure" warning that comes on when under 200 or so bar when on High power, and now understanding that the "low pressure point" for High is 202 bar.....well that's simply it, in a nutshell.
Theoretical entire shot string Since I didn't want to put another 330ish shots over the chrono, the above is an approximation. I recorded the pressure pretty often through all the chronograph shooting (in 10 or sometimes 5 bar increments). That allowed me to try to envision what the programming was doing, but also enabled me to create the above, without shooting another horrifically long shot string over the chronograph (funny to gripe about a shot count that is TOO high-seems backwards). So, the first 182 shots came from the shot string from a few days ago, 244-165 bar. The rest of the string, 144 shots, came from the programming done today, 165-110 bar. It's not exactly like shooting them all through consecutively, but for shot strings longer than 3/5 of a tin of pellets, it'll have to do. It can easily be noted that my programming from 165 down is the more consistent section of the string. I do believe I'm going to call it good here though, considering the intended use does not require a tighter ES than seen here. Besides, can't really turn my nose up at a tune doing 326 shots, all within a tight enough spread to stick a pellet in a FT kill zone.
Current state of the Medium/FT power level programming: Current tune in left column, factory settings in right column (minus the error in the factory voltage that was previously explained)
It's also kind of interesting to compare my 20fpe programming to the factory "Low" 31fpe settings (available in a previous post if you're curious).
Moving on After finishing out the above shot string, I wanted to make sure the gun was still behaving when filled to 250 bar, so refilled it and took some shots with it up that high. The first 5 shots average 803.3fps so I felt pretty good about it. I also wanted to make sure that messing with Medium power didn't have any effect on factory High and Low. High is still doing 870-880 with the 25.39 redesigns. Low is still doing 865-885fps with the 18.13, and still shooting PHENOMENALLY well with this pellet at this speed. My instructor was absolutely spot-on: the three power levels appear to be 100% independent of each other. So, I've got a 45fpe, 31fpe, and 19.5fpe shooter to do testing with now. Sweet.
At this point the gun went back into the stock and I was glad to be done with the programmer.
After all of that, come to find out that the barrel does not like the 13.43gr JSB that I had set my sight on as the magic bullet (pellet) for Field Target. I shot for a couple hours and just couldn't get that pellet to behave. I investigated all the normal culprits. I tried different pellet lots. I lubed up some pellets. Tried different moderators, and no moderator. I even thought I was having scope shift issues and mounted up an old-trusty scope to make sure. No dice, still having flyers with the 13.43gr JSB. (Insert giant, first-world problem, airgun dammit here.)
Before I forget, at 20fpe this gun is backyard friendly WITHOUT a moderator. Without a moderator, just the factory shroud, it is quieter than my JM kitted HW50s springer (and that's a smooth shooting quiet springer). With the Tatsu on and at 20fpe it sounds like a clap? And with the Decimeater it sounds about like a light switch being pushed,
This kind:
CRAZY quiet. Possibly the quietest 20fpe airgun that I've ever shot. Click and then SMACK, the pellet hits the cardboard target backing. Very cool to experience.
So back to the 13.43gr JSB not working out. Here's my hypothesis: this JSB design/weight runs small in the head size department and the RW barrel doesn't run as small as some of the regular Lothar barrels. I am guessing that is intentional to allow for shooting of slugs. All this is based on how tight the NSAs are to chamber in my .22 Veteran barrel, and how much that gun LOVES the 13.43JSB at 20fpe (CZ barrel in Veteran seems like it's a tad small). Combine that with the same box of NSAs chambering much more easily in the RW barrel, and not even being able to feel the 13.43s hit the forcing cone/lead in the RW. I think the head size is just a bit too smalle for this particular barrel. With the 14.3s and 15.89s I can feel the pellet making the transition into the barrel, which makes me think more appropriate head size, and supported by how those pellets are shooting, compared to the 13.43s.
The proof is in the pudding. These are ten shot groups from a bumbag (first time with the RW from a bumbag today), below the tins are at 30 yards, and above the tins are at 53 yards.
Check out that 30 yards group from the 15.89!!!!! 10 easily under a dime, FROM A BUM BAG!!! Shooting that was one of those really cool airgunning moments that will stick with me for awhile.
The 14.3 group at 30 was also quite respectable.
Conclusion As bad as I wanted the gun to like the 13.43, it just doesn't. 2 inch groups at 53 just isn't gonna cut it for FT, especially when I know what kind of accuracy this gun is capable of. The best accuracy seemed to be coming from the 15.89gr, but it's only doing 720fps with my FT power level (so much lost fpe here further reinforces my thought that the JSB 13.43 is undersized for this particular barrel-usually heavier pellet weight in a PCP makes fpe go UP, not down). I could likely bump up the fps (across the whole pressure range) a hair by just increasing the voltage 0.5-1 volt, but I'd still have a VERY loopy trajectory at around 750fps for sub 20fpe. It's kinda seeming like the most reasonable compromise is going to the 14.35gr JSB (in the middle in the above pic). They shot a very good 30 yard group, and put 10 into just a bit over an inch at 53 yards-that's passable FT accuracy. The 14.35s are doing 770-780fps, still legal. That's probably the direction I'll head with my FT intentions for this gun.
Funny little side story If you look at the target above you'll see that I have two, 10 shot groups at 53 yards with the 15.89 and 13.43 but only one with the 14.35. I actually took the shot #1 of a planned 10 with the 14.35 and then my father in law stepped into the garage (wife had sent him out to check out the RW). He's been showing a little interest in airguns here lately. I think to myself, ha ha, what better first one to check out than a DAYSTATE REDWOLF. So, I run out a fresh target to 53 and stick a big orange target at the 30 yard bucket. I set back up the table and get the bags stuffed under the gun. He takes a seat and I could tell from behind that he was nowhere near lined up. Got him lined up on the 53 yard pellet trap and he still couldn't tell what he was looking at. Scope is a 10-50x60 so it takes a little muscle memory to get it all straightened out. I threw the lever over to get it down to 10x and he was still struggling a bit. He finally found it and I just told him to hold crosshairs wherever he wanted the pellet to go (it was already clicked in to poi). He took his first shot and I saw it. That, the airgunning industry just hooked a big one, smile. That, "holy $Hi# this is cool!" response. He took another shot and got another big grin. He was all excited to walk down range and check it out. Both of his shots were inside the 1inch black circle he was aiming for, not too shabby, not too shabby at all. Ha ha.
It may not be at max, but it sure is efficient as is.
