Talking max. shots per fil --- Which are your champions in .22 and .177 ?

[KnifeMaker]

My bone-stock Gen2 fortitude is pretty darn efficient.  70+ shots at 710 FPS in .22- and I still wasn't dropping off the regulator.  There's room for more efficiency, but I'd say Crosman done me right.

I'm not as worried about max shots since air is mostly free, though I have a HUMA reg sitting around that I really need to install in my Leshiy.  Only problem is I'm torn between downtuning the Leshiy in .22 for shot-count versus up-tuning in .25 (or even .30) for smackdown power.  It depends on whether some coyote we've seen stick to the area or keep moving south.

Yeah, mostly free, well, until ya start compressing it that is. OUCH!!!

[Ex.Magnum]

What i ve been looking for when starting this topic,

Is a fairly air-efficient airgun

1.   shooting high BC projectiles in a flat trajectory (hence at higher power levels)
2.   in .22 with the lighter slugs such as 17,5gr NSA, 20,2gr NSA
3.   or in .177 with 18gr NSA, 15,5gr NSA, or even 13,43gr Redesigned Monster JSB’s


In this context,
I ve been wondering if a Kral Super Jumbo barrel would tolerate the Nielsen slugs, launching them with accuracy at 60-65m targets (about 70yards) and beyond.

Anyone ever shot NSA slugs from a Kral Jumbo or Super Jumbo ?

Anyone here who has experience with the Kral Super Jumbo on 15,5 gr and 18 gr Nielsen slugs in .177 ?

I wonder what kind of shotcount can be expected from that settting?

[redlined_b16a]

My brother has the Kral Putbull.
750cc tanks.
On med. Power I believe its over 150 shots in the powerband with 14 grain .22.
High power setting is just over 100 shots.

Not sure what low power shot count is.

My gauntlet with the stock 21ft lb setting in. 22 got 92 shots on the regulator.
Added a 22ci tank and increased reg pressure I now get 87 shots at 28 ft lbs.

[anti-squirrel]

It doesn't matter what tank/tube size is, the bottom line is OP is looking for efficiency meaning shots-per-fill using slugs without stating anything about the power level.  Slugs are typically heavier, thus need more air than pellets to go at a certain velocity, thus would >generally< not be as efficient for lengthening shot-count.

so a lower-power airgun that is shooting mild pellets at a mild velocity, like my Gen 2 Fortitude using 14-grain .22 wadcutters at 690 FPS- gets a whole bucket of shots very accurately using that smallish airtube.

[Ribbonstone]

Really hope the Super Jumbo advertized numbers aren't true....the .177 numbers are terrible.

Can't really do an efficiency calculation without an end pressure.....know the volume,start pressure, advertized shot count, advertized energy....just don't know the bottom pressure.  Can plug in a guess, but it'sjust a guess.

So looking at it simply.....taking their numbers as true....both the .22 and the .25 are getting something like 4550-4700 foot pounds per fill.

But the poor miss-tuned .177 has to be set up as real air hog to only get 2500 foot poundsper fill.

[Ex.Magnum]

...
Can't really do an efficiency calculation without an end pressure.....know the volume,start pressure, advertized shot count, advertized energy....just don't know the bottom pressure.  Can plug in a guess, but it'sjust a guess.
...

@Ribbonstone

About the .177 Super Jumbo, I ll just lay this before you, if i may :

1.   Suppose I m putting in an Altaros reg set at 120 (end pressure 115bar)
2.   Suppose I m opening up the .177 SJ airways, lifting it to 27-28fpe working energy


To your best possible estimate, what in such case is to be expected as a ‘realistic shotcount’ with such a Kral Super Jumbo in .177, shooting 13,46gr Redesigned Monster JSB , or 15,5gr Nielsen, on a 250bar - 500cc bottle?

[Ribbonstone]

  Simple way would be to consider the 4600 total energy per fill listed with the .22 and the .25....so if tuned as well as you could to get the .177/ 15.5gr.up to 900,it should be able of close to 160. Thier listes specs.  for the .177  just don't seem right (168shots,but 15 foot pounds).

There is an energy penaltywith little bores....but their listed specs are way out of proportion.


Running the calculator.
http://www.calc.sikes.us/1/index.php

Plugging in every thing you gave me,except the shot count....just fiddling around with the vel. to get up to your senergy level, then changing the shot count until you get an efficiency of something like 1.3 FPEcuin.....maybe 160 shots.

Which is pretty darn closed to the simple estimate.

HAve no idea if 1700psi (the regulator set) will make it to 27 foot pounds in .177 easily...suspect it would NOT get the efficiency....probably more like 140shots.

[Ex.Magnum]

...probably more like 140shots.

Thx Ribbonstone. That was about my raw estimate too, a good 130 shots per fil. (in the best possible scenario that is, and only when shooting 13,43gr JSB Monster). Shooting slugs might perhaps end up in shotcounts lower than i m hoping for, anyway also much depending on technical specs of the Kral barrel.

Have a splendid weekend.

[Ribbonstone]

Using that fill-in-the-blank efficiency calculatorwith best guesses to what we don't kno for sure can give a pretty good apporximation.
Just an estimation...don't expect it be more accurate than 10-15% as we really don't know the efficiency (so just assumed something reasonable).
You had an energy goal rather than a velocity goal,but I do find it takes a bit more air to drive slugs (probably a bearing area/friction thing)to the same speed as pellets of the same weight.

[Ex.Magnum]

...
it takes a bit more air to drive slugs (probably a bearing area/friction thing)to the same speed as pellets of the same weight.

Indeed, furthermore also much depending on technical specs of the Kral barrel, as indicated.

I wonder if there's anyone around on this platform, with any practical experience as to shooting slugs from a Kral Jumbo barrel, a Kral Super Jumbo barrel, or from any other comparable Kral barrel.

[Blacktalon6]

I get around 65 shots with my Talon SS in .22