Huben Latest GK1 wunderpistol wonderment

[AirNGasman]

What a wonderful read! I'm a wee bit younger than you so my memory begins with the Beeman P1. I remember being amazed at this power when it was introduced.

Quick question if I may. GIven that you won state and nationals, you are likely well versed on the GK1 accuracy. Have you tested it at 50 yards and 100 yards range, and can comment as to it's accuracy potential? Is MOA within its capability at that kind of distances?

Thanks for any insight.

Given my shooting competition experience and also having done more serious air pistol accuracy testing at 50 yards with more tack-driving powerful air pistols than probably anyone else, think I approach accuracy potentials about as closely as human hands can. But when I talk about accuracy, unless stated otherwise I'm talking about calculated AVERAGE accuracy of multiple, consecutive, five-shot groups (at least 3 groups, usually 5 or more); not the best group, no cherry picking groups, no throwing out fliers or bad groups.

The best average accuracy I've gotten with air pistols at 50 yards has been .66 to .67" center-to-center (call it 2/3"); that with four relatively powerful air pistols of 10 to 20+ foot pounds. All achieved occasional half-inch/half-MOA groups. My GK1 is not that accurate.

On one hand one can consider 3/4 - 1" GK1 average groups at 50 yards almost as acurate as 1/2 to 2/3"; on the other hand, not nearly as accurate. I consider it almost as accurate for all practical purposes. But not for Field Target competition. Neither is the GK1 an FT pistol in other ways; too small, too light, and not a competition-worthy trigger. No, the GK1 doesn't have MOA accuracy capability. But neither is that realistic at 50 to 100 yards with any air pistol (especially 100 yards).

But as a hunting air pistol the GK1 is pretty much in a class all its own. Nevertheless, 75 yards is extreme small game pistol range; be it with air or fire powered handgun. My .221 Fireball 10" barreled Contender pistol averages 3/4 to one MOA at 100 yards from sand-bagged bench-rest every time... but humans can't in hunting situations (except as a fluke).

I consider starling-sized game to 75 yards to be stretching GK1 accuracy limits, but have achieved that more than once. "Your mileage might vary."

.

 

[JungleShooter]

Given my shooting competition experience and also having done more serious air pistol accuracy testing at 50 yards with more tack-driving powerful air pistols than probably anyone else, think I approach accuracy potentials about as closely as human hands can. But when I talk about accuracy, unless stated otherwise I'm talking about calculated AVERAGE accuracy of multiple, consecutive, five-shot groups (at least 3 groups, usually 5 or more); not the best group, no cherry picking groups, no throwing out fliers or bad groups.

The best average accuracy I've gotten with air pistols at 50 yards has been .66 to .67" center-to-center (call it 2/3"); that with four relatively powerful air pistols of 10 to 20+ foot pounds. All achieved occasional half-inch/half-MOA groups. My GK1 is not that accurate.

On one hand one can consider 3/4 - 1" GK1 average groups at 50 yards almost as acurate as 1/2 to 2/3"; on the other hand, not nearly as accurate. I consider it almost as accurate for all practical purposes. But not for Field Target competition. Neither is the GK1 an FT pistol in other ways; too small, too light, and not a competition-worthy trigger. No, the GK1 doesn't have MOA accuracy capability. But neither is that realistic at 50 to 100 yards with any air pistol (especially 100 yards).

But as a hunting air pistol the GK1 is pretty much in a class all its own. Nevertheless, 75 yards is extreme small game pistol range; be it with air or fire powered handgun. My .221 Fireball 10" barreled Contender pistol averages 3/4 to one MOA at 100 yards from sand-bagged bench-rest every time... but humans can't in hunting situations (except as a fluke).

I consider starling-sized game to 75 yards to be stretching GK1 accuracy limits, but have achieved that more than once. "Your mileage might vary."

.

Ron,

you're awesome.

And I mean it.


AGN has some very cool people.... ️

Matthias

 

[Ultralight]

Given my shooting competition experience and also having done more serious air pistol accuracy testing at 50 yards with more tack-driving powerful air pistols than probably anyone else, think I approach accuracy potentials about as closely as human hands can. But when I talk about accuracy, unless stated otherwise I'm talking about calculated AVERAGE accuracy of multiple, consecutive, five-shot groups (at least 3 groups, usually 5 or more); not the best group, no cherry picking groups, no throwing out fliers or bad groups.

The best average accuracy I've gotten with air pistols at 50 yards has been .66 to .67" center-to-center (call it 2/3"); that with four relatively powerful air pistols of 10 to 20+ foot pounds. All achieved occasional half-inch/half-MOA groups. My GK1 is not that accurate.

On one hand one can consider 3/4 - 1" GK1 average groups at 50 yards almost as acurate as 1/2 to 2/3"; on the other hand, not nearly as accurate. I consider it almost as accurate for all practical purposes. But not for Field Target competition. Neither is the GK1 an FT pistol in other ways; too small, too light, and not a competition-worthy trigger. No, the GK1 doesn't have MOA accuracy capability. But neither is that realistic at 50 to 100 yards with any air pistol (especially 100 yards).

But as a hunting air pistol the GK1 is pretty much in a class all its own. Nevertheless, 75 yards is extreme small game pistol range; be it with air or fire powered handgun. My .221 Fireball 10" barreled Contender pistol averages 3/4 to one MOA at 100 yards from sand-bagged bench-rest every time... but humans can't in hunting situations (except as a fluke).

I consider starling-sized game to 75 yards to be stretching GK1 accuracy limits, but have achieved that more than once. "Your mileage might vary."

.

Thank you! As JungleShooter commented, "Awesome."

Given that you have forgotten more than I'll ever learn about airgun accuracy, your insights are invaluable so that I know the outer limits of the GK1. I see many convert it to a carbine format with the shoulder stock and given the 40-60 ft-lbs power, I wondered if perhaps100 yards is achievable for hunting smallish game birds.

May I ask if your accuracy test is for the .22 or .25 GK1? Or both? And would one caliber be clearly more accurate over the 50-100 yard range, each with optimum pellets?

Thanks again! Back to the Beeman P1. In those pre-internet days, I remember poring over that Beeman catalog, reading every word from the first to last page. I probably still have some of the catalogs stashed somewhere.

 

[AirNGasman]

Thank you! As JungleShooter commented, "Awesome."

Given that you have forgotten more than I'll ever learn about airgun accuracy, your insights are invaluable so that I know the outer limits of the GK1. I see many convert it to a carbine format with the shoulder stock and given the 40-60 ft-lbs power, I wondered if perhaps100 yards is achievable for hunting smallish game birds.

May I ask if your accuracy test is for the .22 or .25 GK1? Or both? And would one caliber be clearly more accurate over the 50-100 yard range, each with optimum pellets?

Thanks again! Back to the Beeman P1. In those pre-internet days, I remember poring over that Beeman catalog, reading every word from the first to last page. I probably still have some of the catalogs stashed somewhere.

FWIW, I've achieved 1 MOA average groups at 100 yards with less powerful air RIFLES than GK1s, with at least 16X rifle scopes. However hundred-yard pistol shooting is some magnitudes more difficult.

As powerful air pistols go, the GK1 is pretty danged small and light. Gven the shroud attachment isn't the most bulletproof arrangement, I wouldn't mount as large/heavy optics as a 16X rifle scope to it. Per the photo above, the little, lightweight 3-7X vintage rifle scope was the most magnification I feel comfortable mounting on my .22 GK. Even with the shoulder stock, that ain't a hundred-yard rig; bench-rest, or not. Too small, too light, too little magnification. Not sure the GK is capable of 1 MOA average at 100 even if it had enough scope (magnification).

My GK1 ia .22, the buddy I bought it from subsequently got a .25, subsequently sold it, and last I heard preferred the .22. I haven't shot a .25 GK, nor want for one simply due to ammo and air expense.

With powerful air rifles and optimum pellets for hundred-yard shooting, I consider .22 and .25 accuracy equals. I'd think the same true with GKs. In my opinion a GK in either caliber is not a hundred-yard small-bird hunting rig.

.

 

[Ultralight]

View attachment 557294

FWIW, I've achieved 1 MOA average groups at 100 yards with less powerful air RIFLES than GK1s, with at least 16X rifle scopes. However hundred-yard pistol shooting is some magnitudes more difficult.

As powerful air pistols go, the GK1 is pretty danged small and light. Gven the shroud attachment isn't the most bulletproof arrangement, I wouldn't mount as large/heavy optics as a 16X rifle scope to it. Per the photo above, the little, lightweight 3-7X vintage rifle scope was the most magnification I feel comfortable mounting on my .22 GK. Even with the shoulder stock, that ain't a hundred-yard rig; bench-rest, or not. Too small, too light, too little magnification. Not sure the GK is capable of 1 MOA average at 100 even if it had enough scope (magnification).

My GK1 ia .22, the buddy I bought it from subsequently got a .25, subsequently sold it, and last I heard preferred the .22. I haven't shot a .25 GK, nor want for one simply due to ammo and air expense.

With powerful air rifles and optimum pellets for hundred-yard shooting, I consider .22 and .25 accuracy equals. I'd think the same true with GKs. In my opinion a GK in either caliber is not a hundred-yard small-bird hunting rig.

.

Thanks for your very helpful comments. I've not considered the rigidity (or lack thereof) of the shroud. I was actually thinking of experimenting with a 21-oz scope that goes up to 12x. I've got to think about this. What I've heard of the GK1 is about 65 yards for hunting smallish birds, so it does seem that 100 yards is likely a pipe dream.

It is interesting that you both preferred a .22. If I heard correctly, .22 dominates in Europe due to the legal power limitations, and .25 dominates in the US. In the .25, one can do a full 17-shot mag with the JSB 25.39 at 880 fps within a narrow power band. I don't know how the .22 compares, but I don't think it can do 17 shots of the JSB 25.39 at 880 fps within anarrowrange. Perhaps the 20.83 or 18.1 grain in .22.

Can you kindly share one final bit of data. WIth your .22 for longer range accuracy, what pellets and fps? Thanks again for all the insights. Great forum with wonderful people!

 

[AirNGasman]

Can you kindly share one final bit of data. WIth your .22 for longer range accuracy, what pellets and fps?

Sure, UL.

After much tuning both when I had only 250 BAR charging capabilities, and after I (now) have 350 BAR capabilities, I located the sweet-spot charge pressures to return at least a full 19-shot magazine within acceptable extreme velocity spreads (30 FPS or less). Of course the velocity and power of those (at least) 19 shot power-bands increased proportional to the charge pressure.

Here are the results achieved at 315 BAR charge pressure with my two preferred pellets, thankfully equally accurate in my .22 GK. Of course the 18.1s are flatter-shooting, but notice the substantial 10% muzzle energy advantage of the 22.07s-

18.1 grain FX, tuned for 310 BAR fill, 23 shot powerband- Low= 912, Hi= 942, ES= 30, SD= 10, Average= 930 FPS/34.8 FPE

22.07 grain JTS, 315 BAR fill, 21 shot powerband- 870/894/24/6.3/882/38.1

I mostly shoot the 22.07s almost exclusively, in case I get the opportunity at a coyote on my 30 acre home-place.

By the way, I'm trying to reduce my keyboarding time; and am also a big believer in/advocate of the most antiquated and efficient form of communication known to Man. Feel free to call me if you need more information.

Regards,
Ron
254-253-1239

.

 

[Ultralight]

Thank you. You are gener

Sure, UL.

After much tuning both when I had only 250 BAR charging capabilities, and after I (now) have 350 BAR capabilities, I located the sweet-spot charge pressures to return at least a full 19-shot magazine within acceptable extreme velocity spreads (30 FPS or less). Of course the velocity and power of those (at least) 19 shot power-bands increased proportional to the charge pressure.

Here are the results achieved at 315 BAR charge pressure with my two preferred pellets, thankfully equally accurate in my .22 GK. Of course the 18.1s are flatter-shooting, but notice the substantial 10% muzzle energy advantage of the 22.07s-

18.1 grain FX, tuned for 310 BAR fill, 23 shot powerband- Low= 912, Hi= 942, ES= 30, SD= 10, Average= 930 FPS/34.8 FPE

22.07 grain JTS, 315 BAR fill, 21 shot powerband- 870/894/24/6.3/882/38.1

I mostly shoot the 22.07s almost exclusively, in case I get the opportunity at a coyote on my 30 acre home-place.

By the way, I'm trying to reduce my keyboarding time; and am also a big believer in/advocate of the most antiquated and efficient form of communication known to Man. Feel free to call me if you need more information.

Regards,
Ron
254-253-1239

.

Thank for being so generous with your knowledge and time. Deeply grateful.