Huben K1 Review And Insight Into Accuracy Problems

Excellent review and really appreciated! I've had a HUGE interest in this piece and would love to see it in a .25 with the accuracy issues seen here and elsewhere addressed. And of course, cleaning the barrel and other parts are at issue. 

Thanks so much again! 

Great Utubes. I am waiting on one myself. Mrodair stated that his supply would be coming with a different LW barrel than what was on his sample. So I have no idea what the twist or bore size will be on the one I receive. Sure would be nice to know for ordering ammo!! Regards, Tom

Part 2:

Great video from the gent.

One thing that strikes me looking at that design.. What happens if you manage to get a jam of a few pellets up the barrel somehow? (I know this is unlikely but I was at the range the other day when someone did this)

You can't remove the magazine to open the breech and rod the pellets out?

Can you even remove pellets from the magazine backwards? So if this did happen the only option may be to empty the mag and rotate while pushing a pellet into a mag slot, then move it and do the same again. Be tricky though.

I like the look of the gun though. Looks nicer than the prototype I saw a while back.

I thought that MRodAir was the only distributor, but it looks like TopGun Air Guns (one of the forum sponsors) is also a distributor according to the Huben site, though I didn't see any mention of the Huben on the TopGun site.

Edit: I just looked again and it's there now...so either I missed it last time somehow, or they just updated their website...

I'm on the fence like some of th others. The video boast on max power, I would have like to see what it was capable of slow a pellet like the 18's down to where they had a chance to be accurate. This want be a gun you'll want to tinker with, when I talked to Peter at TopGun he said when he open the cover it To take a peak there were so many cogs and springs he quickly closed it and never thought about it again. It is very different and looks to be very consistent. Shows much promise if they make a few improvements. A .25 should rock!

I agree a .25 would be really cool, I'd also like to see removal magazines. If it is really that complicated inside I wonder if it will have any reliability issues, I can't imagine that thing being easy to work on.

Thanks for the excellent review. I am glad you discussed barrel twists. I spent most of my life shooting center fire, and barrel twists vs. bullet length is a critical issue when striving for tiny groups at long ranges. Also, the hammerless design may not be that new. If I recall correctly, the Crosman model 760 pump pellet/bb gun does not have a hammer. The bolt is only for pushing a pellet or bb into the chamber. It also has the same firm trigger pull issue that you mentioned with the Huben. With the Crosman 760, the trigger pull got heavier as you pumped more air in it. 

Tell me where Gregor and I differ? We even agree on the performance of the same pellets?
I have watched his review and it is almost identical to mine in every way.

Thanks to Gregor for the further enlightenment. However it seems that the way the Huben works is still not fully understood so perhaps I should tell you more exactly. I had assumed that as soon as the Patent number was known, everybody would have looked at it and learnt the secret, as I did. But that is a Patent Attorney talking so I can translate the patent into ordinary speak. The secret of the Huben is that it has not one regulator but two. The first is the main regulator that is adjustable by means of the Allen key and controls the working pressure just like any normal PCP regulator. It shuts off the air supply when the pressure downstream of the regulator exceeds a maximum value. The second regulator operates in reverse and shuts off the air supply when the downstream pressure is below a minimum value. The two regulators are connected in series and supply air to the firing valve that is a simple return spring loaded dump valve rather like the one in the original Sharp Innova or Sharp Ace. The minimum value of the second regulator is controlled by the rotary adjusting knob and is below the maximum value of the first. Thus without other means no air would ever reach the firing chamber. The clever bit is that the second regulator is bypassed by a bleed valve so that when the firing valve is closed the pressure in the firing chamber will gradually increase until the pressure exceeds its minimum value and the second regulator opens to fully connect the firing chamber to the output of the first regulator. When the gun is fired the pressure in the firing chamber again drops below the minimum value and the second regulator again shuts off the air supply. The firing valve is then shut by its return spring and is locked by the sear which has been disconnected from the trigger as in any semiauto. That is unless the second regulator has been adjusted to a pressure which is too great so that the bleeding air is at a pressure that might hold the firing valve open. This explains the dumping of air from the Huben that happens when the regulators are wrongly adjusted.
Got it? 
Tony

Thank you for explaining the operation. I did not have the nerve yet to ope it my self. So basically the valve operates by the pressure drop difference in the regulated chamber. and if you increase the power you basically lower the pressure threshold of the second regulator / valve and thus allow a bigger amount of regulated cylinder air to be spent (bigger difference in regulators pressure equaled amount of spent air (power) since the volume of the regulated cylinder is constant). Interesting...

PCP airgun

Hi Gregor, found your videos really informative. Any more feedback on the gun with heavier pellets? Do you know whether the new supply of K1s have sorted out barrel issue?

Found some heavier .22 pellets - think these would work in the K1 - they do look a little long?
http://mrhollowpoint.com/6722.html

Apparently a Huben shipment is in as of Wednesday at TGAG. Curious what the first ones who receive them will say.

I'm curious to know if it has a better barrel than the first batch, if it is accurate at long range (80 yds 0r more ) I would have one on the way,i really wanted an Impact or H/bird II, but have been waiting for the K1 also.

Hello! I am preparing a new video with heavier pellets / slugs. There is a problem with all longer pellets - they are not stable at longer ranges. In my opinion, the twist rate is too slow and the barrel is too thin. I will portable put the new video on YouTube next week.