Huben K1 Review And Insight Into Accuracy Problems

Jump to latest Follow Reply
Tanks, Gregor.
yes it does look very mild and rifling starts pretty much immidiately. Which is ok, I'd guess for bolt action that slowly pushes pellet in to barrel.

Huben slams pellet in to barrel at full force - same as revolver bullet goes at maximum psi. 

Here are pics of revolver cone - you cant miss it:)

http://www.google.com/search?sclient=tablet-gws&client=safari&hl=en&q=revolver+forcing+cone&oq=revolver+forcing+cone

Also, I think now I understand why Huben does not recommend to replace barrel - clearance between barrel and magazine is critical. So I think before tightening 3 barrel screws one needs to use thickness gauge to set the gap. 

Revolver gap is 0.02mm. My guess on air rifle it can be even less cause theres no danger of burned powder buildip that causes magazine jams on powder burners.
 
Upvote 0
Hi guys, sorry for late response...
Yes, it is quite complex to change the barrel on Huben K1. Actually it is easy to replace it but complex to adjust it in the correct position. You have to be careful how far in you thread it and you also have to alight it axially with the magazine. But it is not impossible and you do not need any special tools to axially alight the barrel.
I have tried to shoot pellets in water and did no see any damage on them, so I guess the cone is ok...
The gap between the barrel and magazine is not critical though, because of the clever design that Huben uses: Back side of the magazine (where the air blows in) is sealed with a plastic seal with an o-ring. This seal is pushed forward by the pressure when a shoot is taken and pressed against the magazine to make a seal. At the same time this plastic seal pushes the whole magazine forward and the magazine presses against the barrel to make the front seal. There is no air escaping felt when firing (and this is a bullpup so I would notice it on my neck...)
I am sure that smooth twist barrels are great for standard lighter pellets but I don't think they would work well with heavier pellets / slugs because of their non-aggressive twist rate, but if someone would be willing to send me one of those barrels, I would be happy to put it in and test it. :)
We are working with Rojal (http://www.rojal.si/en/) to offer a custom barrel for Huben or better yet Huben with already built in custom barrel. You can find both products here:
http://www.rojal.si/en/shop/airguns/airgun-addons/huben-improved-barrel-5-5.html
http://www.rojal.si/en/shop/airguns/air-rifles/huben-k1-preorder.html
 
Upvote 0
If someone is willing to send it to me, I would be happy to try it out :)
Generally these barrels have a little bigger diameter and therefore need a bigger slug that will not fit in the magazine. Also 1-8" twist will significantly reduce velocity and is also not needed for such short projectiles. Ant the last part: I assume you has in mind to use copper plated bullets that will have too big friction... Remember: airguns have limited pressures.
Just yesterday I wanted to test some 120 grain bullets in my wolverine 303 with 7,65 barrel. It is regulated to 150 bar (I get about over 100 ft-lbs with jsb pellets) and the bullet got stuck in the middle od the barrel :(
 
Upvote 0
Despite what people believe, polygonal does not bring any significant higher velocity in airguns. They do bring higher velocity with firearms but not because the friction is lower but because they are tighter and higher pressure builds up behind a bullet before it enters the rifling... I have tested this in .30 cal (Wolverine303) and the velocities were almost the same with both barrels...
 
Upvote 0
You must log in or register to reply here.
Top Bottom
Back
Home
Forums
Resources
Menu