I was planning on having a longer barrel machined for it(with a threaded muzzle). Knowing the adapter won’t be here for a while, I’ll be having that barrel made sooner than I thought.
May I ask, where you would have your barrel made at? In addition to a GK1 barrel, would they also happen to take on other special orders for barrels of different calibers & lengths? Thanks.
 
I will ask Kelly (Krazcool) if he can do it. If not then I know a few machinists here that can get it done. They can do different calibers and lengths. I’m thinking about doing a .25 barrel and mag since my pistol is a .22

For a few years I’ve been daydreaming about a mini carbine huben. For the carbine project I’ll be going with an 11” barrel in .25

What caliber and length are you thinking?
 
Another 500 pellets through the GK1. At this point I can’t recommend the CPHP’s. Once the magazine got enough pellets through it, it loosened up and the pellets would shift around in it and jam up. Same with the JSB exact jumbos.
I am currently 200 pellets into JTS dead center wadcutters. I like ‘em, no shifting, no jams. Better accuracy.
 
Last edited:
Another 500 pellets through the GK1. At this point I can’t recommend the CPHP’s. Once the magazine got enough pellets through it, it loosened up and the pellets would shift around in it and jam up. Same with the JSB exact jumbos.
I am currently 200 pellets into JTS dead center wadcutters. I like ‘em, no shifting, no jams. Better accuracy.
Are jams taking place as the mag moves the pellets into the breech block (at 10oclock looking from behind)?
 
Another 500 pellets through the GK1. At this point I can’t recommend the CPHP’s. Once the magazine got enough pellets through it, it loosened up and the pellets would shift around in it and jam up. Same with the JSB exact jumbos.
I am currently 200 pellets into JTS dead center wadcutters. I like ‘em, no shifting, no jams. Better accuracy.
Will you be testing out any slugs, such as FX Hybrids, Zan, Nielsen's or the like? I know Gregor had successfully shot some slugs through his GK1, with the heaviest being 48 grain boattails. Thanks a bunch for taking the time to share your results!
 
Why did you ask this? Curious as I never had a Huben.
I’ve been using GTOs in my Huben rifle and they shoot very accurately but because they are tough, they don’t shear and if they get caught, it always causes a jam. I’ve noticed it’s always in that position. That position also happens to be the one that is most open at the rear and so the pellet skirt gets caught when it hits the breech. IMHO, it’s a design flaw - if the guide block behind the mag were of larger circumference, and perhaps closer to the mag, it wouldn’t happen. I’m thinking about how to fix it…
 
I’ve been using GTOs in my Huben rifle and they shoot very accurately but because they are tough, they don’t shear and if they get caught, it always causes a jam. I’ve noticed it’s always in that position. That position also happens to be the one that is most open at the rear and so the pellet skirt gets caught when it hits the breech. IMHO, it’s a design flaw - if the guide block behind the mag were of larger circumference, and perhaps closer to the mag, it wouldn’t happen. I’m thinking about how to fix it…
Thanks, Good info to have. How about a piece of metal tape. Or build metal up with epoxy then sand down to closer tolerance. But if the pellets did not move in the cylinder, that would not be an issue?
 
Last edited:
Thanks, Good info to have. How about a piece of metal tape. Or build metal up with epoxy then sand down to closer tolerance. But if the pellets did not move in the cylinder, that would not be an issue?
That’s correct, but I have yet to find a pellet that stays put! The problem is that pellets are held only by their skirts and the magazine rotation is very strong and produces a lot of shake. No problem with correctly sized slugs.

My sense is the solution needs to be something hard. I think that epoxy would be chewed up quickly.
 
  • Like
Reactions: Nutcracker
Perhaps this is why Huben is still performing tests for the European market? I find is rather odd that there is such a big difference in availability between the US and Europe.

And we're not talking about a few days or weeks either. It's a whopping 2 months difference. I was quite early with my preorder (early May) and it looks like I won't receive it until October.
 
Last edited:
More pellet tests for the GK1:
There are definitely pellets that won’t jam.

The JTS wadcutters in .22 14.89 grain fit nice and tight with no slip or jams after being seating each one. Shooting at 400FPS. Dime size groups at 10 meters off hand, unsupported. Easily gets through 2 mags.

The JSB Exact Jumbo Beast in .22 33.9 grain slide in easy and there is no room to seat them, but 200 pellets in with no jams.
Shooting at 550 FPS. Groups open up to 2 inches ( prob due to my technique and more kick )
Easily blows through 1 1/4” piece of pine.
 
More pellet tests for the GK1:
There are definitely pellets that won’t jam.

The JTS wadcutters in .22 14.89 grain fit nice and tight with no slip or jams after being seating each one. Shooting at 400FPS. Dime size groups at 10 meters off hand, unsupported. Easily gets through 2 mags.

The JSB Exact Jumbo Beast in .22 33.9 grain slide in easy and there is no room to seat them, but 200 pellets in with no jams.
Shooting at 550 FPS. Groups open up to 2 inches ( prob due to my technique and more kick )
Easily blows through 1 1/4” piece of pine.
Do you know if the 25.4gr JSB MRD pellets work in the GK1?
 
Got my pistol Saturday and shot it today. Loads and functions perfectly. Big big surprise though. This thing is LOUD!!!!! Im thinking, how in the world can a moderator tame this beast. No accuracy groups to report but I wore out the end of a 55 gallon drum at about 40 yards. Lots of fun.
Just received mine today also. I agree with how loud it is. Definitely not back yard friendly. Hopefully the moderators work well. Haven’t messed with anything yet.