Here is an other spin off thread for the Huben pistol where members can share what ammo they have found works good,....... or bad in their hand cannon.
Huben Huben pistol ammo choice.
- Thread starter Nomadic Pirate 66
- Start date
Then this may interest you. I will be receiving one of these for Christma. NOE 25-52-FN-BB4 2 cavity RG2 BT Brass bullet mold. They give full specs on their website. Googling it should bring it up. Sounds like exactly what you are looking for as was I.
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Some preliminary results for the gk1. Didn't get to test in the rifle, will see if I can tomorrow.
I shot these groups with a bag rest at 25 yards, open sights. At that distance the green circle is about the same size to my eye as the front sight. Hard to say if I aimed at the same exact spot. I was trying to hurry a bit so rather than fill to 5000 each time from my cs4, I tethered to my great white in the 4200 psi area. For the first group, I didn't notice my valve wasn't open enough, so the bottom shots in that group that make it look terrible may have been due to dropping pressure. Three groups were shot with my new .2537 slugs, one with my older .254s. They all seem similar, will do more testing and really curious to see how the rifle likes them. If it turns out that the 254s remain the most accurate, I may just see if I can get a new pin for my die from corbin to make those solid nose as well instead of hollow point, then I can make them faster too.
It was fairly cold out today
1st group, the one with the valve mistake. Shot with 43.5 grain .2537s
2nd 45.2 grain, .2537
3rd 47.8 grain, .2537
4th 50.2 grain, .254
Considering that with open sights, the front sight completely covers the green circle, I can't complain with this accuracy. Really hoping the rifle likes the .2537s at least as much as it does the .254s
I also tested energy. Without adjusting the power with the hex key between slug types.
The 50.2 grain .254 made 74.97 FPE on the first shot
47.8 grain .2537 made 71.91 FPE
45.2 grain .2537 made 70.44 FPE
43.5 grain .2537 made 69.77 FPE
For the first 6 shots from a max fill, from heaviest to lightest, the average energy was
71.0
68.2
67.3
67.3
I shot these groups with a bag rest at 25 yards, open sights. At that distance the green circle is about the same size to my eye as the front sight. Hard to say if I aimed at the same exact spot. I was trying to hurry a bit so rather than fill to 5000 each time from my cs4, I tethered to my great white in the 4200 psi area. For the first group, I didn't notice my valve wasn't open enough, so the bottom shots in that group that make it look terrible may have been due to dropping pressure. Three groups were shot with my new .2537 slugs, one with my older .254s. They all seem similar, will do more testing and really curious to see how the rifle likes them. If it turns out that the 254s remain the most accurate, I may just see if I can get a new pin for my die from corbin to make those solid nose as well instead of hollow point, then I can make them faster too.
It was fairly cold out today
1st group, the one with the valve mistake. Shot with 43.5 grain .2537s
2nd 45.2 grain, .2537
3rd 47.8 grain, .2537
4th 50.2 grain, .254
Considering that with open sights, the front sight completely covers the green circle, I can't complain with this accuracy. Really hoping the rifle likes the .2537s at least as much as it does the .254s
I also tested energy. Without adjusting the power with the hex key between slug types.
The 50.2 grain .254 made 74.97 FPE on the first shot
47.8 grain .2537 made 71.91 FPE
45.2 grain .2537 made 70.44 FPE
43.5 grain .2537 made 69.77 FPE
For the first 6 shots from a max fill, from heaviest to lightest, the average energy was
71.0
68.2
67.3
67.3
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Incase anyone is wondering
43.5gr = 850 fps
45.2gr = 837.8 fps
47.8gr = 823.2 fps
50.2gr = 820.2 fps
Seems like the difference between the 47.8 and 50.2 is negligible and unless that’s creating substantially better groupings, which (excluding the flier) it doesn’t seem to be, it’s completely beaten out by the 50.2. Thank you for posting results!
43.5gr = 850 fps
45.2gr = 837.8 fps
47.8gr = 823.2 fps
50.2gr = 820.2 fps
Seems like the difference between the 47.8 and 50.2 is negligible and unless that’s creating substantially better groupings, which (excluding the flier) it doesn’t seem to be, it’s completely beaten out by the 50.2. Thank you for posting results!
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It's possible to get a bit more power than I did, but I like to be able to at least get a whole magazine while staying above 12mpa after the last shot, starting at 35 mpa. PCPs seem to make a bit less energy when it's cold out too.
I think I will hit up corbin for a new pin for the .254 die. Should be cheap for just a pin.
I think I will hit up corbin for a new pin for the .254 die. Should be cheap for just a pin.
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@Asher That 50.2 grain group looks the tightest and not as random, less the few flier's. With that heavy slug weight, did the gun/shot cycling seem more calm than with the lighter ammo? Or do you think maybe the extra weight and length attributed to barrel accuracy? Or a combination of both?
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Hard to say for sure. It does seem better though doesn't it. I can't say with certainty that it wasn't me aiming a little better for that one. If anything I think I notice a bit more recoil with the 50 grainers. In terms of calm, hard to say, not sure exactly what that would mean. They were 11mm long. The 47.8s were 10.9mm as I intended them for the rifle too. I may try some of the .2537s in 11mm.
As with the rifle though it may just end up being that .254 is more accurate. Maybe the .2537 die was a waste of time and money. I'll know more soon
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My suggestion would be to get a vice attached to a stone block that you can use to clamp the shroud to test accuracy. Pistols are very difficult to evaluate manually, especially with heavier ammo. That’s what led me to choose the GTOs for use in my 22. The accuracy/consistency at 900fps is stunning. Obviously, it doesn’t have the punch that many people want but it does everything I need sub MOA and flat out to 50y, including dispatching two raccoons.
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The metal scrap yards sell large pieces of plate steel for cheap. I go there a lot to get all kinds of stuff to make things out of, including a piece of thick steel for mounting a vice to test accuracy of guns and scopes.
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Yes I suppose a vice would be better. I don't currently have a suitable one. I have however made some of the .2537s in 11mm, weighing 48.6 grains to test in the pistol, and some 10.9mm .254s and .2537s, weighing 49.3 and 47.8 grains respectively, to test in the rifle. I do have a full rest for the rifle, and a nice scope, so the groups from that should be more informative. What are the odds that better accuracy in the rifle of one slug or the other will translate to the pistol?
With the limited data I have now, it seems the 254s remain king. I did just make an observation though.
In the past, 10.9mm length slugs that my .254 die makes are difficult to seat without a tool, but I'm trying to remember how shiny they were. Seems maybe the ones I struggled with were duller. The recent lead spools I've gotten from NSA have an issue where the outer layers of lead are more weathered than the inner. I can improve it somewhat by cleaning with swage lube, and I've been making an effort to rub the dirty lead harder. This works to a degree, but it remains the Case that the cleaner lead makes better looking, slightly smoother slugs. I just made some at max length and only had a little resistance seating them, I could still use my finger. They were shiny. So with them, maybe seating won't be a big issue if I can get cleaner lead. I plan to mention it to the guys at NSA next time I order lead, ask if I can get it fresh. i store it wrapped in its bag with a silica gel packet and in its box and padding. It worked well to keep some lead I had gotten from crown metals in good condition. Unfortunately the two 25 lb spools I've gotten from NSA both had inferior lead to what I got in the past from crown metals, but NSA is fast and responsive to my orders, crown metals not so much. Anyway it doesn't seem to make a huge difference for the 22s so I maybe I'll use the more dirty lead to make those, maybe even only for myself. Id rather get quality lead though. I plan to order 50lb spools in the hopes that more of the lead will be in the depths of the spool rather than its outer layer. Hopefully I don't get any more sub par lead. If the 254s remain the most accurate, and if I can get better lead or at least only use the better parts of the spool to make them, and if I get another pin to make them solid nose, I'll be in pretty good shape although the .2537 might still have been a complete waste of time. We shall see. Live and learn.
With the limited data I have now, it seems the 254s remain king. I did just make an observation though.
In the past, 10.9mm length slugs that my .254 die makes are difficult to seat without a tool, but I'm trying to remember how shiny they were. Seems maybe the ones I struggled with were duller. The recent lead spools I've gotten from NSA have an issue where the outer layers of lead are more weathered than the inner. I can improve it somewhat by cleaning with swage lube, and I've been making an effort to rub the dirty lead harder. This works to a degree, but it remains the Case that the cleaner lead makes better looking, slightly smoother slugs. I just made some at max length and only had a little resistance seating them, I could still use my finger. They were shiny. So with them, maybe seating won't be a big issue if I can get cleaner lead. I plan to mention it to the guys at NSA next time I order lead, ask if I can get it fresh. i store it wrapped in its bag with a silica gel packet and in its box and padding. It worked well to keep some lead I had gotten from crown metals in good condition. Unfortunately the two 25 lb spools I've gotten from NSA both had inferior lead to what I got in the past from crown metals, but NSA is fast and responsive to my orders, crown metals not so much. Anyway it doesn't seem to make a huge difference for the 22s so I maybe I'll use the more dirty lead to make those, maybe even only for myself. Id rather get quality lead though. I plan to order 50lb spools in the hopes that more of the lead will be in the depths of the spool rather than its outer layer. Hopefully I don't get any more sub par lead. If the 254s remain the most accurate, and if I can get better lead or at least only use the better parts of the spool to make them, and if I get another pin to make them solid nose, I'll be in pretty good shape although the .2537 might still have been a complete waste of time. We shall see. Live and learn.
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Some testing with the rifle today. I wish the results were better but I won't BS you. Here were 50 yard groups with the .2537 max length slugs
Here are the 254 max length at the same distance:
Finally, 2 groups at 100 yards. First is the .2537s
And then the 254s
I think I'm going to polish my barrel and see what happens then. Been meaning to do it for a while now and I have the stuff to do it
Here are the 254 max length at the same distance:
Finally, 2 groups at 100 yards. First is the .2537s
And then the 254s
I think I'm going to polish my barrel and see what happens then. Been meaning to do it for a while now and I have the stuff to do it
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I didn't measure today. I used the same power level it had been on which produced around 920 FPS with a 47ish grain AVS so probably similar or slightly slower
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This 254 slug is actually producing a really good group at 100 yards with the unregulated GK1. The narrow up and down pattern at 100 yards is simply the fluctuation of air pressure and speed.
I looked at my bore with a scope. Most lands and grooves look looks good and one is kind of rough but not too bad. So I'm debating on the polish job with this because it is already such a large bore and is limited to ammo choices "off the shelf" without buying a set of dies to tune with. I have polished all of my air rifle barrels, both successfully and also not so successful. One barrel is not accurate anymore because I opened it up a bit too far, but I have a set of dies on the way to hopefully fix that with sizing.
The GK1 doesn't look like a hard gun to machine an aftermarket barrel to fit into if need be...
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