Disclaimer:
Modifications made to this rifle were performed by an experienced professional airgunsmith. And, proved safe in THIS gun.
No warranties are implied nor extended.
We have no control of what you do on your own.
If you do decide to make ANY modification to an airgun, be conscious of which elements are under force or pressure and realize that, even a "little pre-compression" or as little as 10 BAR's CAN cause SERIOUS bodily harm.
These modifications have not been reviewed, nor approved by DIANA / M&G
Again: Be careful! You are the only guardian of your health and safety.
Modifications made to this rifle were performed by an experienced professional airgunsmith. And, proved safe in THIS gun.
No warranties are implied nor extended.
We have no control of what you do on your own.
If you do decide to make ANY modification to an airgun, be conscious of which elements are under force or pressure and realize that, even a "little pre-compression" or as little as 10 BAR's CAN cause SERIOUS bodily harm.
These modifications have not been reviewed, nor approved by DIANA / M&G
Again: Be careful! You are the only guardian of your health and safety.
Two "personalities" in one model
When the Scotsman, Robert Louis Stevenson, wrote the famous novel: "The Strange Case of Dr. Jekyll and Mr. Hyde", he was writing about a commonplace phenomenon of the Victorian Era.
Persons that were the very image of Gentleness and Propriety in Public, had an underlying strain of lust and bottled up violence that came out under the right circumstances.
In true Victorian fashion, at the time of writing, the novel was purported to portray the inner fight of the "good and evil" personae inside each one of us.
After reading other works by RLS, I have come to the conclusion that it was not that "inner fight" the one that the author was trying to portray, but the desire of the Victorians for more "raw" experiences. Raw in the sense of physical power, of getting things done.
Of course, this was also the time of the magazine/pamphlet/periodical "The Pearl" (you will have to look this one up yourself because it is not for polite company). Which would do the same for the love life of the Victorians.
AND; BTW, it didn't help that it was also the time of the "Jack the Ripper" crimes that never "got solved", probably because they were perpetrated by an "extremely high up personality".
Again the dual sides of getting rid of a problem (real or perceived) in the "proper" way, as opposed to the raw, direct and immediate "final solution".
Just "Food for thought" in our current times.
Now. Back to airguns:
Is power in a spring-piston airgun "evil" in itself?
Hmmmm . . . . Nope!
It all depends on the platform and the purpose.
In previous occasions I have mentioned that the laws and rules that came into effect in the UK of GB and NI in 1968-1969 were drafted by persons that actually knew something about pellets, airguns, and ballistics.
If you factor in the average pellet weight of the era and the MV's most conducive to proper stability, precision, and accuracy you will find that 12 ft-lbs is a REALLY good number.
Perhaps we should say "WAS".
Why? because in the last 57 years, the art and science of making pellets has taken large strides, and nowadays, the medium weight pellets (between 8 and 9½ grs in 0.177" / 4.5 mm's), can now travel excellently well at 875-900 fps, and that is about 14½ ft-lbs. Which, perhaps not unexpectedly, is the point where most AAFTA Open Piston and Hunter Piston shooters tune to.
Still, the International Version of FT clings to the 12 ft-lbs and that makes it an interesting game where marksmanship skills play an all important role. Yes, guns, and especially scopes, play an extremely important role, but at sub-12 ft-lbs, it is the marksmanship skills of each shooter what takes the day.
ALSO, nowadays we have "bigger" pellets. I remember when the JSB Exact "Heavies" came onto the market. They had a long "waist" to achieve the 10.3 grs. weight, The Crosman Premiers of the day, had an almost solid skirt, sealing at the head and just taking the skirt for the ride. These Premier (Heavies) scaled in at 10.5 and the Barakuda Match came in at 10.6 grs.
Later, the JSB H's went through a re-design that made them approach a slug because it has no real "waist". Rather the head and the mini-skirt are linked by a "column". Of course, the pellets themselves being a "flange (not flare) stabilized" projectile do not actually NEED the skirt (as a shuttlecock would).
The end result is a pellet that has VERY good ballistic characteristics when compared to other, more "traditionally made" pellets.
So, when I had the opportunity to make the companion K-98 S to the one described a few months ago, I opted for the "Mr Hyde" version of that Dr. Jekyll.
This one was NOT going to be demure, proper, "educated", or "gentlemanly" in any way. This was going to be a true "Valkyrie" in the sense that it would thrive in power.
And, in order to do THAT, and retain the precision and accuracy needed for our airgun games, we would have to come up with a slightly different architecture.
Last, but not least, we did not want to loose the personality of the K-98 as a "war implement".
If the first one had been the "low" power (still illegally powerful by UK stds.) was the "Auskundschafter" (Scout), this one was going to be the true "ScharfSchützen Gewehr".
After a few weeks of work, this is what we ended with, the left side:
Persons that were the very image of Gentleness and Propriety in Public, had an underlying strain of lust and bottled up violence that came out under the right circumstances.
In true Victorian fashion, at the time of writing, the novel was purported to portray the inner fight of the "good and evil" personae inside each one of us.
After reading other works by RLS, I have come to the conclusion that it was not that "inner fight" the one that the author was trying to portray, but the desire of the Victorians for more "raw" experiences. Raw in the sense of physical power, of getting things done.
Of course, this was also the time of the magazine/pamphlet/periodical "The Pearl" (you will have to look this one up yourself because it is not for polite company). Which would do the same for the love life of the Victorians.
AND; BTW, it didn't help that it was also the time of the "Jack the Ripper" crimes that never "got solved", probably because they were perpetrated by an "extremely high up personality".
Again the dual sides of getting rid of a problem (real or perceived) in the "proper" way, as opposed to the raw, direct and immediate "final solution".
Just "Food for thought" in our current times.
Now. Back to airguns:
Is power in a spring-piston airgun "evil" in itself?
Hmmmm . . . . Nope!
It all depends on the platform and the purpose.
In previous occasions I have mentioned that the laws and rules that came into effect in the UK of GB and NI in 1968-1969 were drafted by persons that actually knew something about pellets, airguns, and ballistics.
If you factor in the average pellet weight of the era and the MV's most conducive to proper stability, precision, and accuracy you will find that 12 ft-lbs is a REALLY good number.
Perhaps we should say "WAS".
Why? because in the last 57 years, the art and science of making pellets has taken large strides, and nowadays, the medium weight pellets (between 8 and 9½ grs in 0.177" / 4.5 mm's), can now travel excellently well at 875-900 fps, and that is about 14½ ft-lbs. Which, perhaps not unexpectedly, is the point where most AAFTA Open Piston and Hunter Piston shooters tune to.
Still, the International Version of FT clings to the 12 ft-lbs and that makes it an interesting game where marksmanship skills play an all important role. Yes, guns, and especially scopes, play an extremely important role, but at sub-12 ft-lbs, it is the marksmanship skills of each shooter what takes the day.
ALSO, nowadays we have "bigger" pellets. I remember when the JSB Exact "Heavies" came onto the market. They had a long "waist" to achieve the 10.3 grs. weight, The Crosman Premiers of the day, had an almost solid skirt, sealing at the head and just taking the skirt for the ride. These Premier (Heavies) scaled in at 10.5 and the Barakuda Match came in at 10.6 grs.
Later, the JSB H's went through a re-design that made them approach a slug because it has no real "waist". Rather the head and the mini-skirt are linked by a "column". Of course, the pellets themselves being a "flange (not flare) stabilized" projectile do not actually NEED the skirt (as a shuttlecock would).
The end result is a pellet that has VERY good ballistic characteristics when compared to other, more "traditionally made" pellets.
So, when I had the opportunity to make the companion K-98 S to the one described a few months ago, I opted for the "Mr Hyde" version of that Dr. Jekyll.
This one was NOT going to be demure, proper, "educated", or "gentlemanly" in any way. This was going to be a true "Valkyrie" in the sense that it would thrive in power.
And, in order to do THAT, and retain the precision and accuracy needed for our airgun games, we would have to come up with a slightly different architecture.
Last, but not least, we did not want to loose the personality of the K-98 as a "war implement".
If the first one had been the "low" power (still illegally powerful by UK stds.) was the "Auskundschafter" (Scout), this one was going to be the true "ScharfSchützen Gewehr".
After a few weeks of work, this is what we ended with, the left side:
As far as length, weight, balance, and overall "feel" this one feels just like the "real thing".
The grip, the shouldering, the LOS, the weight. With your eyes closed you would swear you are holding a vintage K-98 made in the late 1910's
On the right side the mystery is revealed:
The grip, the shouldering, the LOS, the weight. With your eyes closed you would swear you are holding a vintage K-98 made in the late 1910's
On the right side the mystery is revealed:
There is no bolt. So, you're safe shooting this in your backyard. It MAY raise a few eyebrows, but . . . just be safe and courteous when the SWAT team arrives.
;-)
;-)
The Full Power Tune
For the ~12 ft-lbs version, we made an Ultra-Light Piston and calibrated the weight of the TopHat to JUST yield the 13 ft-lbs the owner desired.
For this one, a Mid-weight piston yielded initially well over 900 fps. And so, the Titan #1 had to be strain set and then, still doing about 900 fps, reduced by ¾ of a coil to manage a more stable and accurate velocity for the JSB H's:
Strings of 30 shots gave us these results:
For this one, a Mid-weight piston yielded initially well over 900 fps. And so, the Titan #1 had to be strain set and then, still doing about 900 fps, reduced by ¾ of a coil to manage a more stable and accurate velocity for the JSB H's:
Strings of 30 shots gave us these results:
If you do the calculations, these MV's put the K-98 S in the 18.5 ft-lbs. with the full length spring, 17.6 ft-lbs. with ¾'s coil lopped off, which is pretty much what I wanted.
Add a low sample Standard deviation and you can be confident that, as long as the barrel likes the pellets, it will be an accurate and precise combination. In graphic terms:
Add a low sample Standard deviation and you can be confident that, as long as the barrel likes the pellets, it will be an accurate and precise combination. In graphic terms:
This type of power and stability is PCP territory.
With the exception that the shot string can be as long as the shooter's biceps and elbows hold, LOL!
In the previous version we did not need to get rid of any "lost volume", the weight of the TopHat was tailored to the power output, so there were no high pressure gases still behind the pellet when the pellet exited the muzzle.
In this case, we knew we had to solve an excess of air being pushed about because accelerating a 10.5 grs. pellet at 8,500 g's for the full 430 mm's of barrel travel would need a vortex diverter. AND, yes, this is a real number, if humans pass out at 7-8 g's, just imagine what 8,500 g's mean.
So taking advantage of the threaded muzzle of the K-98 S, we installed this:
With the exception that the shot string can be as long as the shooter's biceps and elbows hold, LOL!
In the previous version we did not need to get rid of any "lost volume", the weight of the TopHat was tailored to the power output, so there were no high pressure gases still behind the pellet when the pellet exited the muzzle.
In this case, we knew we had to solve an excess of air being pushed about because accelerating a 10.5 grs. pellet at 8,500 g's for the full 430 mm's of barrel travel would need a vortex diverter. AND, yes, this is a real number, if humans pass out at 7-8 g's, just imagine what 8,500 g's mean.
So taking advantage of the threaded muzzle of the K-98 S, we installed this:
Anyway, our pellets are so good that they do take that outlandish acceleration and fly to the target with some degree of controllability.
But the controllability increases if you make sure that the pellet flies through "calm air" as soon as it goes out of the muzzle. There are some "pundits" that maintain that the spin of the pellet is mostly needed to get across the "mushroom" of turbulence created when the pressurized gases exit and overtake the pellet in its path. While that is a partial truth, it is not the whole, sole, and unadulterated, truth. Recent productions of custom barrels with slow twists have shown that SOME spin is still beneficial.
On the side, I also use the location of the moveable brass weight to tune to some extent the harmonics of the barrel.
For reasons that should be obvious when you analyze the way the gun disassembles and (if you have not read the previous note, do so now, to understand how this barrel becomes an exercise in rigidity once the whole thing) is put together again, these are much lower than in other versions of the D 460 (of which the K-98 S is one variant), but it is still nice to have some degree of controllability in that.
Finally, as part of keeping in the character of the K-98, we needed some "battle sights". Which we found with the Tech sights for grooved receivers:
But the controllability increases if you make sure that the pellet flies through "calm air" as soon as it goes out of the muzzle. There are some "pundits" that maintain that the spin of the pellet is mostly needed to get across the "mushroom" of turbulence created when the pressurized gases exit and overtake the pellet in its path. While that is a partial truth, it is not the whole, sole, and unadulterated, truth. Recent productions of custom barrels with slow twists have shown that SOME spin is still beneficial.
On the side, I also use the location of the moveable brass weight to tune to some extent the harmonics of the barrel.
For reasons that should be obvious when you analyze the way the gun disassembles and (if you have not read the previous note, do so now, to understand how this barrel becomes an exercise in rigidity once the whole thing) is put together again, these are much lower than in other versions of the D 460 (of which the K-98 S is one variant), but it is still nice to have some degree of controllability in that.
Finally, as part of keeping in the character of the K-98, we needed some "battle sights". Which we found with the Tech sights for grooved receivers:
A detailed image:
Because we were planning to use this rifle with iron sights for some precision shooting, it was essential to have some sort of "peep" sight that would give us a long and low sight radius, which these sights achieved with great success.
The sight picture is quite clear:
The sight picture is quite clear:
The shooting
Now, why we were thinking about using iron sights?
Well, DIANA has made a commitment to support the Boerne Schützenfest. Last year I was unable to attend because it coincided with the FT Nationals; having been to a few over the years and over the world, I can tell you that they are a lot of fun.
Mostly because they are usually held as some part of an "Oktoberfest" (the agricultural harvest starts in September and ends in October), which of course, involves some good food, some good beer, and some good company.
Target is challenging, though it is not difficult to get a high score because the center is worth 25 points, and the black goes down to the 18. Missing the last "white" ring of 17 gives you zero points, but as long as you keep them all in the "black", you are doing good.
When the gun was tested with a reduced version of the target (for 10 meters), this was the result:
Well, DIANA has made a commitment to support the Boerne Schützenfest. Last year I was unable to attend because it coincided with the FT Nationals; having been to a few over the years and over the world, I can tell you that they are a lot of fun.
Mostly because they are usually held as some part of an "Oktoberfest" (the agricultural harvest starts in September and ends in October), which of course, involves some good food, some good beer, and some good company.
Target is challenging, though it is not difficult to get a high score because the center is worth 25 points, and the black goes down to the 18. Missing the last "white" ring of 17 gives you zero points, but as long as you keep them all in the "black", you are doing good.
When the gun was tested with a reduced version of the target (for 10 meters), this was the result:
After the first "Cold Bore" shot, the remaining 10 shots went into a group smaller than a dime.
The K-98 amazes me in how "shootable" it is.
Further testing in true "match" fashion yielded good results.
This is with the iron sights:
The K-98 amazes me in how "shootable" it is.
Further testing in true "match" fashion yielded good results.
This is with the iron sights:
It was the best card of the night's six, but it still shows that disciplined shooters can shoot well with "battle" irons.
Another session, this time testing with the 2-7 X 42 scope set at 3½X yielded TWO good cards (again, out of 6):
Another session, this time testing with the 2-7 X 42 scope set at 3½X yielded TWO good cards (again, out of 6):
Why are the targets "pink"? because if they are black you cannot discern your hits . When they are printed in "pink" you can clearly see your impacts, even with iron sights.
Perhaps not quite as good as the first one (one point lower), but there were TWO in this session and that tells you that it is easier to be consistent with even a small scope, than it is to be consistent with "battle" irons.
Next test with the Schützen target will be with irons, but with an aperture up front (Korntunnel). And then we will see what happens. But that will be later and we'll use my Tyrolean D54 (of course, what else would be appropriate? ;-) )
Perhaps not quite as good as the first one (one point lower), but there were TWO in this session and that tells you that it is easier to be consistent with even a small scope, than it is to be consistent with "battle" irons.
Next test with the Schützen target will be with irons, but with an aperture up front (Korntunnel). And then we will see what happens. But that will be later and we'll use my Tyrolean D54 (of course, what else would be appropriate? ;-) )
Before I forget:
A note on the scope used:
It is made by Viiko
A note on the scope used:
It is made by Viiko
And it has a peculiar reticule:
A close-up of the reticle shows that, apart from the "rangefinding stadia wires", it also has POI drop marks:
It is a SFP variable, which will lend itself well to stadia-ranging. And we altered the parallax to 25 yards. Not complicated in simple scopes.
As the parallax was shortened so did the Eye Relief and, so, from an almost "pistol scope" eye relief it is now in the "High recoil" scope region. It can be mounted forward to have "situational awareness" at low mags, and also dialed up to provide precision and accuracy when the shot allows the time to do so. It would make quite an interesting hunting scope.
It is an inexpensive scope (which encourage customization) and the optics are good enough for some airgun uses.
The reticle gives me some ideas that I need to test, if those pan out, it may be a VERY interesting experience, LOL!
The Mount had to be "sculpted" to fit the rather large saddle and erector spring assemblies, but it is working well.
Now, would this be a good rifle for longer ranges?
Definitely YES!
This is how the rifle prints at 25 meters:
As the parallax was shortened so did the Eye Relief and, so, from an almost "pistol scope" eye relief it is now in the "High recoil" scope region. It can be mounted forward to have "situational awareness" at low mags, and also dialed up to provide precision and accuracy when the shot allows the time to do so. It would make quite an interesting hunting scope.
It is an inexpensive scope (which encourage customization) and the optics are good enough for some airgun uses.
The reticle gives me some ideas that I need to test, if those pan out, it may be a VERY interesting experience, LOL!
The Mount had to be "sculpted" to fit the rather large saddle and erector spring assemblies, but it is working well.
Now, would this be a good rifle for longer ranges?
Definitely YES!
This is how the rifle prints at 25 meters:
5 shots well under a dime and 10 shot groups under or at the dime o-o.
And beyond?
This is a 10 shot group at 55 yards / 50 meters:
And beyond?
This is a 10 shot group at 55 yards / 50 meters:
Yes, there are 10 shots there. The stray shots on the left, outside the "Sighting" square, belong to other groups.
With a 7X scope and hold-off's, this is mighty rewarding in a windy day at DIFTA.
Would I use this setup for AAFTA Hunter?
I am seriously considering it.
MAYBE I would have to install a better scope, maybe a Veyron, or something like that. But the capabilities of the rifle are amply demonstrated.
AFAIK, there are no more K-98 S's on the retailers shelves, but the 460 is still in the lineup and perhaps there are some here and there in the warehouses.
While this one may be the Mr. Hyde impersonation of a raw and unpolished element. it is also true that the gun is a "wahre Walküre" ready to take to the action fields.
Keep well and shoot straight!
HM
With a 7X scope and hold-off's, this is mighty rewarding in a windy day at DIFTA.
Would I use this setup for AAFTA Hunter?
I am seriously considering it.
MAYBE I would have to install a better scope, maybe a Veyron, or something like that. But the capabilities of the rifle are amply demonstrated.
AFAIK, there are no more K-98 S's on the retailers shelves, but the 460 is still in the lineup and perhaps there are some here and there in the warehouses.
While this one may be the Mr. Hyde impersonation of a raw and unpolished element. it is also true that the gun is a "wahre Walküre" ready to take to the action fields.
Keep well and shoot straight!
HM
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