They work just fine but sure expensive to waste on targets. I've been catching H&N 20.06 on sale way cheaper to waste on targets and fairly accurate.
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Huben .25 Slugs for GK1?
- Thread starter FLgunner
- Start date
in my few years experience with huben, and talking to kelly a lot, the hubens magazines vary from batch to batch. when i got my 2024 k1 limited, i couldn't even get .223 slugs to stay in it - they fell through and jammed. I had kelly put a .218 magazine in it from a 2018 batch he had, and after that all was good. I shoot .2193 slugs and larger sized pellets (jsb still slip and jam).
So, no one size of pellet or slug will fit everyone's GK1. They do tend to size large, so that is a good starting place, but you will have to experiment a little to get the best ammo for your gun.
So, no one size of pellet or slug will fit everyone's GK1. They do tend to size large, so that is a good starting place, but you will have to experiment a little to get the best ammo for your gun.
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the only slugs that fit mine tight enough is .254. This might be a stupid question but they are supposed to be hard to push in,correct?
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no more than firm. past that and you are starting to swage it a bit, and will get some build up...
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Hi Bandito I’m replying to you as I don’t want all and sundry to find out about these as what happens is everyone goes crazy and then you can’t get them I was tired of slugs getting stuck not cycling properly but it was a couple of things I put a quick loader on and that was just touching the magazine at certain points so had to sand down before putting it back on and I started using a pellet, it gives you faster flight, greater Accuracy, Deeper penetration/31grn/ 2g exactly, did you know they used 2.2 g when testing the gk1 for all there test spec results , anyway they’re called panther Heavy Metal Pellets, 150per tin about £7 ish but touch wood never had a Problem with them yet Happy shooting 
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The only projectile I could find that would never jam was .254 42 grain AVS flat slugs. Every pellet and slug that I tried would move around in the mag unless you kept the gun level. Even then the recoil would move them. Seating them (pushing them in a little helped but still got a jam once in a while. As far as the loading gate, it's supposed to be .1-.2 mm gap. You can use A4 paper as a shim because it's the perfect width. Last summer, every Sunday I shoot 160 shots in my league. The entire summer not one jam with the AVS 42's. I would love to have a lighter projectile that wouldn't jam but have tried everyone except your recommendation. I will try it. ThanksHi Bandito I’m replying to you as I don’t want all and sundry to find out about these as what happens is everyone goes crazy and then you can’t get them I was tired of slugs getting stuck not cycling properly but it was a couple of things I put a quick loader on and that was just touching the magazine at certain points so had to sand down before putting it back on and I started using a pellet, it gives you faster flight, greater Accuracy, Deeper penetration/31grn/ 2g exactly, did you know they used 2.2 g when testing the gk1 for all there test spec results , anyway they’re called panther Heavy Metal Pellets, 150per tin about £7 ish but touch wood never had a Problem with them yet Happy shooting
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I got them from an online shop called (ihunter) they pretty much do everything plus there’s a market place to buy and sell outwith the store itself I hope those pellets hit the spot for you cheers.
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I see you looking for tight fitting ammo to prevent jamming. When I first got my GK1 it would jam pretty consistently. You are probably more knowledgeable about this gun than me, but have you adjusted the cycling screw on the back right of the handle? I read a post by a Huben repair guy about this adjustment. I did it to mine and it hasn't jammed or degassed since, even though my ammo is far from tight in the cylinder.
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What?!! Im not denying your fix but those screws in the back are for the adjustment of the 1st and 2nd stage of the trigger.
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The left screw controls the trigger staging, but the one on the right controls the speed of the cylinder cycling. If the cycling is too fast it makes the gun get ahead of itself and it jams. The guy that invented this pistol has a good video in which he demonstrates the varying of the cycling speed. To correct the problem you are having back out on the right screw slightly. Video is on youtube under GK1.
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huh. It was always my understanding since it was a two stage trigger you can adjust each stage like all other high end airguns. I guess you learn something everyday. thanks
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I do not believe that is correct. I've seen most of Gregor's videos on the gk1. The two screws are for trigger stages. What did happen to me though was I set my trigger fairly light. Then, after some number of shots at high power, (and therfore probably more vibration) the screw that sets the triggers break weight worked itself looser, making the break weight more and more loose until it was so loose that the gun would double fired on me and sometimes jam (which is my best guess as to what caused my barrel ring damage) I've since set the trigger break weight a bit heavier than where I'd like it and pay more attention to it to avoid this but i can say with virtually 100% certainty that neither of the screws, nor any adjustment on the gun controls the cycle speed
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Thats what I thought. He also mentioned a degasing issue. I was having a degasing issue when I was shooting at high power and the power adjustment screw eventually vibrated out do to recoil. Now I set my power and put a dab of loctite on the power screw. This way it wont come loose and hasn't so far.
So just to be clear the two screws in back are to adjust the 1st and 2nd stage trigger break.
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Yes and I've had that issue with my power adjustment too. Kept increasing power until it was so high that it used too much air on one magazine and I didn't notice, and shot with not enough air causing a jam.
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You need to go back and review Gregor's video on that. When he is adjusting the right grip screw the pistol increases mag rotation to the point that it advances more than one chamber. Then he decreases the setting and it goes back to one chamber. It sure is hard to help someone on this forum.
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OKay, I went back and reviewed Gregor's video on trigger adjustment. You guys are right, both screws are for trigger adjustment. What I had picked up on was when he adjusted the second stage it was possible to make the gun multi fire. All I know for sure is that my GK1 was jamming and dumping air until I tightened up on the second stage. I don't have this problem any longer and my gun will shoot any tightness of projectile. I mistakenly claimed the function of the second stage adjuster. I apologize, but I still recommend a slight clockwise turn on the screw. Evidently ,too light of a trigger keeps the system from resetting
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yes it does. take off the trigger guard and put a dab of loctite on the side of the power screw as well. Thats another way you can get a jam if you dont.
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I bet you didn't buy your GK1 from Kraz Cool. Kraz goes through and loctites and checks every problem screw and other things that can go wrong with the airgun. He even takes the tank off and hydro tests each one. He does this not only for good customer service but he has to service the gun if it breaks to. Did you know that most broke GK1's go to him and the other retailers call him because they only sell and cant service them. He will probably kill me if he sees this post but if you buy from him he even fixes them for free when there out of warranty.
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