Karma Airguns Slug Testing: Statistically Significant Groups?

Ask five airgunners what slug works best at grouping well at 50-yard tuning groups and at long range, and you’ll probably hear five different answers. The truth is, it’s not only about slug weight or twist rate. One of the biggest considerations a lot of airgunners don't realize is how well-suited that slug is for your bore size. It might be the most important variable when attempting to get slugs to perform well out of your specific rig. But what about all these groups we see on social media and here in the forums with amazing results? Well, there is often a story behind those groups and understanding that story will make you a more educated airgunner with real-world expectations.

50 Yard Grouping

At 100 yards and beyond, things get real and tell the full story when it comes to slug testing. Some air rifles will stack them at 50 yards and fall apart beyond that, but one thing I will guarantee is that this fallacy of a slug's ability to group at 100 if it was garbage at 50 is totally wrong. There is this concept we have seen posted for years in the online forums of projectiles going to "sleep" at a distance, leveling out their stability. If you have ever watched scope cam footage or witnessed yourself through your scope on a sunny day at the range, when a projectile starts to destabilize, there is no amount of "going to sleep" that is gonna fix the point of impact. We've seen pellets happen to spiral into a nice group because of a consistent instability that just so happens to have them spiral into a decent group, but move that target distance a bit forward or back, and now you have a shotgun pattern.

100 Yard Grouping

The other thing to point out is when we see those picture-perfect, tiny five-shot groups you see all over social media? It sometimes takes a bit of tuning and testing to get there. We are all a bit guilty of showing our best 5-shot groups, but we won't share those unless we know that is typical of our overall results on average. With that said, the importance of understanding statistical shot dispersion is important for every airgunner. If you have an MOA airgun slug and tune combo, you will 100% get some groups that open up after you shoot a statistically significant number of shots. It isn't ego or skill or sponsored content creation; it is just physics and statistical probability.

We've been digging into real numbers and testing from air rifles like the Karma lineup and FX platforms. If you’ve ever scratched your head wondering why your air rifle feels lights-out one day and inconsistent the next, or why a slug that looks great at 50 falls apart at 100, this is the discussion worth having. So how do you test your long-range slug performance? Do you trust small sample groups, or do you run the numbers until you see the full picture? This is a good, honest conversation to have... Let's hear it!
 
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Ask five airgunners what slug works best at grouping well at 50-yard tuning groups and at long range, and you’ll probably hear five different answers. The truth is, it’s not only about slug weight or twist rate. One of the biggest considerations a lot of airgunners don't realize is how well-suited that slug is for your bore size. It might be the most important variable when attempting to get slugs to perform well out of your specific rig. But what about all these groups we see on social media and here in the forums with amazing results? Well, there is often a story behind those groups and understanding that story will make you a more educated airgunner with real-world expectations.

View attachment 588833

At 100 yards and beyond, things get real and tell the full story when it comes to slug testing. Some air rifles will stack them at 50 yards and fall apart beyond that, but one thing I will guarantee is that this fallacy of a slug's ability to group at 100 if it was garbage at 50 is totally wrong. There is this concept we have seen posted for years in the online forums of projectiles going to "sleep" at a distance, leveling out their stability. If you have ever watched scope cam footage or witnessed yourself through your scope on a sunny day at the range, when a projectile starts to destabilize, there is no amount of "going to sleep" that is gonna fix the point of impact. We've seen pellets happen to spiral into a nice group because of a consistent instability that just so happens to have them spiral into a decent group, but move that target distance a bit forward or back, and now you have a shotgun pattern.

View attachment 588834

The other thing to point out is when we see those picture-perfect, tiny five-shot groups you see all over social media? It sometimes takes a bit of tuning and testing to get there. We are all a bit guilty of showing our best 5-shot groups, but we won't share those unless we know that is typical of our overall results on average. With that said, the importance of understanding statistical shot dispersion is important for every airgunner. If you have an MOA airgun slug and tune combo, you will 100% get some groups that open up after you shoot a statistically significant number of shots. It isn't ego or skill or sponsored content creation; it is just physics and statistical probability.

We've been digging into real numbers and testing from air rifles like the Karma lineup and FX platforms. If you’ve ever scratched your head wondering why your air rifle feels lights-out one day and inconsistent the next, or why a slug that looks great at 50 falls apart at 100, this is the discussion worth having. So how do you test your long-range slug performance? Do you trust small sample groups, or do you run the numbers until you see the full picture? This is a good, honest conversation to have... Let's hear it!
Well………

First of all the Karma EQ .30 cal has an oversized barrel. I couldn’t get anything to a decent speed or to group consistently until I tried some 62gr .303 and .306 Varmintknockers. The .303 do slightly better than the .306s and are doing about 935fps for 120fpe and at least one full mag a tune. The .306s do about 10fps less.

As for slug tuning I’m not expert but I do ONLY shoot slugs out of my barra 250z and my EQ. I like to adjust the reg until the slug is going slightly faster than my intended target speed. Then I back the hammer spring off a little to get the speed I want.

It’s really that simple. It takes longer to go through different slugs and see which one the gun likes better than it actually does to tune it.

I don’t shoot targets very much. I don’t have the attention span or patience to sit and shoot group after group. Especially with the .30 cal since the slugs are more expensive than .25 and .22…

I shoot enough groups to zero the gun and check that the slugs are flying consistently. Then I input the info into the ballistics app, check the hold overs, then start shooting at rocks, cans or whatever. If the real world results match the app then I know I’m on the right path… after that I go shoot critters.

I’m don’t think I’ve ever shot an MOA group at 100y with any gun this even a powder burner. I’m 99% sure my 250z will do it if I ever get out on a day with no wind and try. I probably won’t though haha.

I know my slug tune is good when I can do what you see in the video before. The wind call and drop were are taken from the dnt app after imputing the correct info. Beyond that I’m just a noob trying to figure things out… my insta/youtube is just videos like this. Mostly with my 250z… so maybe it’s just better to be lucky than good?😂😂😂


Karma Eq .30 cal
86 yards
62gr .306 V.knockers slug @925fps

 
"There are lies, damn lies, and Statistics" (Twain, via Disraeli)

After taking several college stats courses and even more business stats courses, I found that data presentation is usually skewed to support the presenters bias. Not just via stats, it is human nature.

That said, stats are a valuable tool...but for 99.44% of shooters, it is too data intensive to be of much use...nor is it fun (for most). It is all well and good that we have chronos that spout basic stats. Correlating those stats to group size, outdoors, is an exercise in futility. As you said, groups at 50 won't usually geometrically fit the same MOA at 100. Even indoors, the cone of fire isn't a perfect 1:1.

So, what do we do? Is there a golden stat? A magic pill?

If there was, we'd be spending $$$$ to track that stat, shooting the one true rifle, and using the slug King Arthur pulled out of the stone.

I like using stats. Keep them simple, useful (it is often difficult to determine if you're tracking the right data point) and don't let data get in the way of having fun. It is a variable world out there.
 
"There are lies, damn lies, and Statistics" (Twain, via Disraeli)

After taking several college stats courses and even more business stats courses, I found that data presentation is usually skewed to support the presenters bias. Not just via stats, it is human nature.

That said, stats are a valuable tool...but for 99.44% of shooters, it is too data intensive to be of much use...nor is it fun (for most). It is all well and good that we have chronos that spout basic stats. Correlating those stats to group size, outdoors, is an exercise in futility. As you said, groups at 50 won't usually geometrically fit the same MOA at 100. Even indoors, the cone of fire isn't a perfect 1:1.

So, what do we do? Is there a golden stat? A magic pill?

If there was, we'd be spending $$$$ to track that stat, shooting the one true rifle, and using the slug King Arthur pulled out of the stone.

I like using stats. Keep them simple, useful (it is often difficult to determine if you're tracking the right data point) and don't let data get in the way of having fun. It is a variable world out there.
 
I welcome this discussion although I think the title might better be “Airgun Futures…” There is a treasure trove of information on many of the topics about precision & accuracy currently under discussion on this forum which have been addressed in books earlier by intelligent and experienced shooters such as Bryan Litz (four volumes), Keith Siewert, Geoffrey Kolbe and,
especially, Harold Vaughn.
There is a lot more to discuss about this general subject but I would like to start by emphasizing the future is more than pellets & slugs. In my opinion, a pellet is an aerodynamic ******** a small ball with a tail on it. The term slug is a misnomer. Slug connotes something slow, cumbersome & ugly, or a DIY after-thought for a shotgun shell. In this case, we should be talking about precision projectiles, examples such as Berger bullets. Walt Berger catapulted to the top of competitive shooters by redesigning his bullets with the J4 jacket and surpassing tolerances in concentricity / offset CG of less than one ten-thousandth inch. In the airgun world we are far from that precision today.
More to come…
 
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Well………

First of all the Karma EQ .30 cal has an oversized barrel. I couldn’t get anything to a decent speed or to group consistently until I tried some 62gr .303 and .306 Varmintknockers. The .303 do slightly better than the .306s and are doing about 935fps for 120fpe and at least one full mag a tune. The .306s do about 10fps less.

As for slug tuning I’m not expert but I do ONLY shoot slugs out of my barra 250z and my EQ. I like to adjust the reg until the slug is going slightly faster than my intended target speed. Then I back the hammer spring off a little to get the speed I want.

It’s really that simple. It takes longer to go through different slugs and see which one the gun likes better than it actually does to tune it.

I don’t shoot targets very much. I don’t have the attention span or patience to sit and shoot group after group. Especially with the .30 cal since the slugs are more expensive than .25 and .22…

I shoot enough groups to zero the gun and check that the slugs are flying consistently. Then I input the info into the ballistics app, check the hold overs, then start shooting at rocks, cans or whatever. If the real world results match the app then I know I’m on the right path… after that I go shoot critters.

I’m don’t think I’ve ever shot an MOA group at 100y with any gun this even a powder burner. I’m 99% sure my 250z will do it if I ever get out on a day with no wind and try. I probably won’t though haha.

I know my slug tune is good when I can do what you see in the video before. The wind call and drop were are taken from the dnt app after imputing the correct info. Beyond that I’m just a noob trying to figure things out… my insta/youtube is just videos like this. Mostly with my 250z… so maybe it’s just better to be lucky than good?😂😂😂


Karma Eq .30 cal
86 yards
62gr .306 V.knockers slug @925fps

Interesting information! I also have the eq 30. I tried different slugs. Fx hybrids were the worst. All were standard size 30cal though. I settled on aea 52.2gr .
 
I welcome this discussion although I think the title might better be “Airgun Futures…” There is a treasure trove of information on many of the topics about precision & accuracy currently under discussion on this forum which have been addressed in books earlier by intelligent and experienced shooters such as Bryan Litz (four volumes), Keith Siewert, Geoffrey Kolbe and,
especially, Harold Vaughn.
There is a lot more to discuss about this general subject but I would like to start by emphasizing the future is more than pellets & slugs. In my opinion, a pellet is an aerodynamic ******** a small ball with a tail on it. The term slug is a misnomer. Slug connotes something slow, cumbersome & ugly, or a DIY after-thought for a shotgun shell. In this case, we should be talking about precision projectiles, examples such as Berger bullets. Walt Berger catapulted to the top of competitive shooters by redesigning his bullets with the J4 jacket and surpassing tolerances in concentricity / offset CG of less than one ten-thousandth inch. In the airgun world we are far from that precision today.
More to come…
I do think we are reaping the benefits of an arms race in the “slug” world. First the Ace slugs came to blow everyone’s BC’s out of the water in .22… early reports make it seem like the Zan ELRs are gonna compete with them.

I doubt that this is gonna anything other than push the “slug” game to even higher levels.
 
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Okay… so quick update:

I still have some testing to do before I get carried away but I think I found a 71gr HYBRID Boat tail in .303 that the EQ loves.

She’s spitting them out at 900fps for 127fpe.

I have to order more since these are from a sampler but when they arrive I think I’m gonna have to sit and do some grouping with this one.

I’ve never tried a 150 or 200yard group. Curious what this slug can do on paper.

I already know it’s gonna devastate any coyote it touches. The slug is like .500 long but the cavity is like .200 deep! Can’t wait to hear the thwack.