Huben pistol.

[Pale_Rider]

@mil You had issues with each one of those pellets/slugs?

The h&n hornets could pose an issue if they can don’t sit really tight in the mag; the pointed tip could slide forward and jam up the mag.

As for the heavy pellets/slugs: If shot at too low of a speed the open valve will remain open and dump the air. But you’re saying the issues happened at speeds over 790 fps?

 

[mil]

Yes to all questions

 

[Ezana4CE]

Got scope and a 0db 110c on there.
Was popping the 2"spinner at 50 yards 5/5.
Just a .22 shooting pellets tho! I never could get slugs to work well in the huben mags, pellets work so well I stopped trying!

View attachment 383892

Which slugs have you tried?

 

[Pale_Rider]

Yes to all questions

That is odd. Now I’m wondering if huben is using a barrel with a smaller diameter for the GK1 and it’s causing too much friction with these larger diameter slugs; which in turn is causing the valve to stay open and dump air. What else is odd: is @weevil has been shooting slugs out of his gk1 with no issues.

 

[Ezana4CE]

@weevil @mil are you two seating your slugs in the mag before shooting?

 

[wimpanzee]

Which slugs have you tried?

a lot of them heh. up to .219s were still sliding forward enough to snag the mag.

 

[beerthief]

I started with a 350 BAR nitrogen fill. I shot 8 magazines full. That’s 152 shots. Starting FPS was 459 and last shot was 343. Not one malfunction! Without the gate installed I can load 5 without indexing the mag. So it’s 5,5,5,4. I called it quits when the reg was at 120 BAR.

View attachment 383722

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I am very interested in Nitrogen as it is available locally to me , and it is dry so no extra filters to add. , can you describe your fill system , anything special needed ? Thanks Stan in KY .

 

[longshot81]

I'm using a 40 grain Apollo slug in my 25 cal and I haven't had any problems and I don't even have to push them down with the tip of a pen. I just put them in and push them with my finger and they seed just fine and shoot like a champ. I have mine doing 838 fps with a those slugs.

 

[weevil]

That is odd. Now I’m wondering if huben is using a barrel with a smaller diameter for the GK1 and it’s causing too much friction with these larger diameter slugs; which in turn is causing the valve to stay open and dump air. What else is odd: is @weevil has been shooting slugs out of his gk1 with no issues.

Note that mine is a 22, so not a direct comparison. Also when I inspect the slugs after shooting into duct seal, the rifling marks look identical to those from my 22 rifle, so I have no reason to suspect that the 22 barrel diameter is different.

I’ve been through all the BS with the rifle in relation to ammo staying put in the magazine and I use a modified golf tee to seat pellets and slugs. The longer Altaros require quite some push and I cannot imagine that they (or the AVS) will move. My slugs are lubed with HBN. Another reason I favor the GTOs is that they are rigid enough to click in place and stick. Whenever, I evaluate pellets for these guns, I check the visible chambers between shots to see if the pellets have freed up. I have not yet found a lead pellet that does in fact stay put when the mag cycling starts to shakes them up. That includes the JTSs, which some claim are oversized. Thin, soft pellet skirt vs. aggressive air powered mag rotation? We really need proprietary pellets for these guns, and for me, the GTOs are simply the best available option in that sense.

Regarding mil’s gun, there could be some issue in the action causing the problem. I was leery about pushing mine to shoot the 36g slugs. With no reg and at high fill pressures, pushing 50g slugs may be putting a lot of strain on the valve components that in the rifle are working with a max of 200bar. I’ll certainly be settling on using the GTOs and 22grain AVS if they play nice together. The Altaros part of the experiment was just for S&Gs.

For those experiencing what sound like serious safety issues, I strongly advise returning those guns…

 

[weevil]

I'm using a 40 grain Apollo slug in my 25 cal and I haven't had any problems and I don't even have to push them down with the tip of a pen. I just put them in and push them with my finger and they seed just fine and shoot like a champ. I have mine doing 838 fps with a those slugs.

Yes, they are undersized. We’ve been through this process with the K1 rifles. If spin is not imparted by the rifling, they can be dangerously inaccurate.

 

[weevil]

I am very interested in Nitrogen as it is available locally to me , and it is dry so no extra filters to add. , can you describe your fill system , anything special needed ? Thanks Stan in KY .

I can explain mine. I have a 6000 psi Airgas tank which is around $100 bucks to refill (use 2 per year and refill at 3000psi. It has an Airgas regulator (around $700) and a coupling that leads to a male foster. Filling a gun from the big tank is a PITA, so I use an Air Venturi carbon tank as a shuttle. Another advantage of nitrogen is that it’s a bit lighter than “nitrogen laden with oxygen and carbon dioxide (aka. Air)”, so you get a 1-2% boost in power/speed for free! I am one of those folks who doesn’t treat compressors well so the cost of nitrogen vs. replacing compressors is a wash.

 

[Nutcracker]

I had the first chance to test mine out properly in the desert where neighborly relations wouldn’t be strained! I wanted a solid sense of its accuracy before I decide on an optic, so it was temporarily fitted with a pic rail adapter and a 5X Vortex prism optic. It was supported solidly on rice bags for the testing and I used a bubble level stuck on top of the action to prevent error from cant. Short of clamping it in a vice, I consider this to be a very solid “benchrest quality” test. I tried three types of ammo that I find to be the best in my 22 K1 rifle: Predator GTOs, AVS 22 grain .223 dished slugs and Altaros ATP 36 grain Huben slugs (also .223). For the record, I find the GTOs to outperform any lead pellet in the rifle. I attribute this to their hardness, which I think prevents deformation during the transition from mag to barrel. Lastly, I cleaned the barrel between each ammo type with my quick and easy method:

Huben K1 barrel cleaner (edit: works for .22 and .25)

Just sharing a hack devised to clean the K1 barrel quickly and easily. My friend and owner of a 25 confessed that he had never cleaned his barrel (3 years and many thousand shots!) because he didn’t want to get into any disassembly. We set about crafting a device to clean it that doesn’t...

www.airgunnation.com

With each ammo, I first found the pressure bounds that gave tight SDs at my target speeds. 890 for the GTOs and AVS slugs. Tapped out, the heavy Altaros were shooting at 800 and I tested those for accuracy tethered at 260bar because I didn’t have the means to go higher and speed was descending from that pressure. That’s 50fpe and with no mod, it’s a thunderclap. Maybe a bit more juice can be squeezed out with a compressor fill but I only had a tank available.

Ok, enough nerdy details. The accuracy testing was at 55 yards with 8 shot groups. No wind, no fliers to blame on the gun, doin my absolute best. Even with the Altaros, it’s a peach to shoot and I had no issues with jams. The lack of recoil/flip is remarkable and a major compliment to the semi auto functionality. As others have said, the trigger sets a new standard for semis and I have no desire to futz with it.

The icing on the cake?

I can explain mine. I have a 6000 psi Airgas tank which is around $100 bucks to refill (use 2 per year and refill at 3000psi. It has an Airgas regulator (around $700) and a coupling that leads to a male foster. Filling a gun from the big tank is a PITA, so I use an Air Venturi carbon tank as a shuttle. Another advantage of nitrogen is that it’s a bit lighter than “nitrogen laden with oxygen and carbon dioxide (aka. Air)”, so you get a 1-2% boost in power/speed for free! I am one of those folks who doesn’t treat compressors well so the cost of nitrogen vs. replacing compressors is a wash.

I agree. I have had nitrogen for over a decade. The only downside to me Is moving that heavy nitrogen bottle. But I don't shoot as much as a lot of you guys I only get mine replaced once a year if that. I take it back to the welding supply house when it gets to 3000 psi. They do pickup and delivery too. Nitrogen saves you from worrying about moisture and poor-quality compressors etc. Then I have a great white that I take to my hunting cabin and just leave it there from September to February, it supplies all I need for the hunting season.

Got a groundhog yesterday evening at 45 yards with my GK1 850 fps Hades one shot. I like this pistol.

 

[elwoodblues]

You guys are doing it the hard way just get a std pressure Nitrogen tank and a cheap flowgauge feed that to whatever compressor you use for HPA
you never have to turn in a tank with 3000 psi left in it and can use it down to about 100 psi. Every compressor I have ever seen has a single point of air in take just need a fitting to match that. A GX cs-2 has a 1/2" npt thru the handle most have a filter that can be replace with a fitting usually 1/4 npt they ussually call it a muffler.
No moisture or oxdizers o2 co2 in compressor or guns win win.

 

[beerthief]

You guys are doing it the hard way just get a std pressure Nitrogen tank and a cheap flowgauge feed that to whatever compressor you use for HPA
you never have to turn in a tank with 3000 psi left in it and can use it down to about 100 psi. Every compressor I have ever seen has a single point of air in take just need a fitting to match that. A GX cs-2 has a 1/2" npt thru the handle most have a filter that can be replace with a fitting usually 1/4 npt they ussually call it a muffler.
No moisture or oxdizers o2 co2 in compressor or guns win win.

wonderful , so i can use a 6000 tank and when it gets down to gun fill pressure i can fill with my compressor ? right ? sounds good to me. i only have 3 PCP but they are all top tier guns and i don't shoot them that much, and i do notlike the current H2O separator filters .

 

[elwoodblues]

You do need to regulate the pressure down to about 10 psi to feed the compressor

 

[weevil]

I’ve considered that but for me, the tanks and airgas deliveries work just fine.

 

[Pale_Rider]

Note that mine is a 22, so not a direct comparison. Also when I inspect the slugs after shooting into duct seal, the rifling marks look identical to those from my 22 rifle, so I have no reason to suspect that the 22 barrel diameter is different.

I’ve been through all the BS with the rifle in relation to ammo staying put in the magazine and I use a modified golf tee to seat pellets and slugs. The longer Altaros require quite some push and I cannot imagine that they (or the AVS) will move. My slugs are lubed with HBN. Another reason I favor the GTOs is that they are rigid enough to click in place and stick. Whenever, I evaluate pellets for these guns, I check the visible chambers between shots to see if the pellets have freed up. I have not yet found a lead pellet that does in fact stay put when the mag cycling starts to shakes them up. That includes the JTSs, which some claim are oversized. Thin, soft pellet skirt vs. aggressive air powered mag rotation? We really need proprietary pellets for these guns, and for me, the GTOs are simply the best available option in that sense.

Regarding mil’s gun, there could be some issue in the action causing the problem. I was leery about pushing mine to shoot the 36g slugs. With no reg and at high fill pressures, pushing 50g slugs may be putting a lot of strain on the valve components that in the rifle are working with a max of 200bar. I’ll certainly be settling on using the GTOs and 22grain AVS if they play nice together. The Altaros part of the experiment was just for S&Gs.

For those experiencing what sound like serious safety issues, I strongly advise returning those guns…

I found out about the superb accuracy with GTO’s, in my K1, three years ago. Good to know someone else found that out too. And I’m confident it’s for the same reason you mention.

 

[weevil]

I found out about the superb accuracy with GTO’s, in my K1, three years ago. Good to know someone else found that out too. And I’m confident it’s for the same reason you mention.

View attachment 384100

Wonderful, legionair - thanks for letting me know! Hopefully, a few people here will try them in the pistol. I do a lot of shooting into duct seal, which gets very soft in the sun and will soak up even lead pellets without them getting deformed. Shooting from the K1, I can often see head or skirt damage with lead pellets, which must come from the gun. The GTOs just have perfect rifling marks.

 

[Boomstrike]

I did some accuracy testing today, 25 cal with a baseline of 800 fps with the jsb 25.39 from a bag rest

 

[Boomstrike]