Inferno slugs

Kral arms
inferno slugs

                     Inferno Air Rifle Slugs

Air Rifle Slugs have recently become very popular as the industry is delivering more powerful air rifles almost on a daily basis. Air rifles shooters have realised the advantages that slugs bring over traditional pellets when used at the longer distances than these air rifles are capable of.

Inferno has not just jumped onto this “new bandwagon” as some new manufacturers have, by cloning some of the existing slugs of other manufacturers, as to take advantage of the new, developing slug market. We have produced, precision, hand swaged, jacketed, center fire bullets for top competition shooters as well as hand swaged, jacketed, premium bonded bullets, for the hunting industry. Using swaging processes also does not guarantee a precision bullet or slug. As with any manufacturing, it takes lots of time and dedication to gain the experience to deliver a guaranteed and quality product consistently. We have used the experience we have gained over many years and our own shooting to develop slugs with specific ogives, nose and base configuration to ensure we deliver a proven, quality product in every slug we make. Unfortunately some of the “new manufacturers” will flood the market with inconsistent and inferior products that might work the one day but not the next, however this is expected and as always will fizzle out over time.

The best advice we can give consumers is to ensure that the manufacturer you choose, uses the cleanest of lead and not recycled lead from scrapyards as not any lead can be used for pellets and slugs. You are guaranteed to ruin your barrel over time should the lead used in the pellets or slugs you shoot in your air rifle not be top quality. This happens much more than expected, especially within a new market as is the case with air rifle slugs.  

Slugs are manufactured in various ways i.e. casting or swaging

Inferno air rifle slugs are hand-swaged. The same method used for bullets manufactured for center rifle shooters competing at the highest levels. Bullet swaging is a method of using very high pressure (approaching 80,000 PSI) at room temperature to force a lead core into a copper jacket to form a bullet. Our slugs are manufactured using the same process, but as slugs do not consist of a copper jacket the lead core is swaged directly into precision, diamond lapped dies. Unlike casting, no heat or molten lead is used. The high pressure is applied with special, powerful presses; each designed to hold a precision, diamond-lapped die.

Inferno precision swaged slugs almost always have better concentricity than cast or mass-produced slugs, they have an extremely high degree of uniformity and density, and the process allows for very excellent repeatability. Being able to make the same slug time after time is very important and swaging excels at this. The end result is the most accurate slug possible.

Our slugs are exact caliber diameter, measured up to 5 digits after the comma, i.e. 0.21700″ diameter at the bearing surface. By using precision equipment we ensure that weights are very consistent, less than 0.1 grain variance of the intended weight. There is absolutely no reason to weigh and handpick these slugs in batches for competition use, as is the case with the top brands of pellets and casted, or mass manufactured slugs.

e make various nose and base configurations in each caliber. This is important when choosing a slug. As in centerfire bullets there are not one bullet that can do everything.

Choosing the correct slug for the correct application will dictate the configuration needed. 

Flat bases have slightly more bearing surface area, while boat tail bases are more aerodynamic and have a slightly higher ballistic coefficient (BC) than flat bases.

Boat tails have slightly less bearing surface and less dynamic core pressure, which provides less friction in the barrel. This increases their velocity from flat base bullets of the same weight and they are more stable for longer distance shooting, because they have a lower drag coefficient and produce less air turbulence. Boat tails are less precise than flat base bullets, as adding the boat tail there is potential for imperfections, i.e. making the boat tail off center (Depending on the quality of dies used). Also, boat tails are more susceptible to muzzle blast and may cause the bullet to pitch and yaw, and they require a higher twist rate to stabilize. The reason why boat-tails are sometimes preferred, over other base configurations, is that at extended ranges, the aerodynamic benefits overcome atmospheric variations better than flat bases, and make up for the marginally compromised precision potential. 

Inferno precision swaged slugs have been tested extensively over the last year by International and South Africa’s top air rifle shooters, in many different air rifles and have proved to shoot under MOA accuracy when rifles are setup correctly.” 

As the slug weight, bearing surface, ogive, differs from each slug, you must experiment with different power settings, seating depth etc. to find the slug that suits your specific rifle the best. Although most manufacturers would like you to believe that their air rifles, pellets or slugs shoot MOA groups at 100 meters “out of the box”, be sure that this is rarely the case. As with pellets you have to put in the time to test different combinations in YOUR air rifle, don’t expect one hole grouping right out of the box until after you’ve done your experimenting with all the variables.

A major advantage you will have with our slugs is that we will constantly update our website and social media pages with exact specifications of all our slugs, rifles they have been tested in, true BC’s measured and the exact setups that have been accurate. This will not only give you a starting point reference of what will work in your rifle but will also save a lot of time in testing and costs to find the right combination for your air rifle.

Air Rifle Slugs – Specifications

See the explanations below regarding the different slug calibers, nose and base configurations for our current range of Air Rifle Slugs.

Different slug calibers currently in production
Range of air rifle slug calibers that we manufacture

Different slug calibers nose and base configurations currently in production
Different Nose and Base configurations possible in our range of Air Rifle Slugs

See below more detail on the different nose configurations of our air rifle slugs.

air rifle slug hollow point nose configuration
Hollow Point

Advantages :

  • Much better expantion
  • Shorter than a Spitzer at the same weight
  • Functions better in multi-shot magazines

Disadvantages :

  • Slightly lower BC (really small difference)
air rifle slug spitzer point nose configuration
Spitzer Point


  • Slightly higher BC (really small difference)


  • Might cause problems in certain multi-shot magazines
  • Longer than a Hollow point at the same weight

See below more detail on the different base configurations of our slugs.

air rifle slug hollow base configuration
Hollow Base

Advantages :

  • One can produce very light slugs for their length, suitable for less powerful Air Rifles that would normally not be able to shoot slugs.
  • Provide great expansion at the base during firing, ensuring that it seals the barrel.

Disadvantages :

  • Base more susceptible to damage during transport and handling
  • Less BC at same weight compared to other designs
air rifle slug flat base configuration
Flat Base

Advantages :

  • Traditional proven design in the industry.
  • Very accurate
  • Good BC
  • Works well in multi-shot magazines

Disadvantages :

  • Base less susceptible to damage than Hollow Base but more than Cup Base
air rifle slug cup base configuration
Cup Base

Advantages :

  • This design is a custom design developed by Inferno after a significant amount of testing with various base configuration
  • Least like to damage during transportation and handling.
  • Very accurate
  • Good BC
  • Works well in multi-shot magazines
  • Flat inside base to ensure the probe seats it straight in the chamber/barrel.

Disadvantages :

air rifle slug rebated boat tail base configuration
Rebated Boat Tail Base

Advantages :

  • This design is a custom design developed by Inferno after a significant amount of testing with various base configuration
  • Provide great expansion at the base during firing, ensuring that it seals the barrel.transportation and handling.
  • Very accurate
  • Best BC (small amount over Flat and Cup bases)
  • Works well in multi-shot magazines
  • Flat base to ensure the probe seats it straight in the chamber/barrel.

Disadvantages :

  • Rebated edge can be susceptible to damage during transportation and handling

History of the Cup Base design for Air Rifle Slugs

“The Inferno Cup Base design was developed from what the industry normally terms a “Concave Base”. During testing we found that the concave, inside base, caused some probes to seat slugs often slightly skew in the chamber/barrel which negatively impacts accuracy. We therefor changed the normal concave design of the inside base to be flat, ensuring that most probes seat the slugs straight in chambers/barrels. Additionally, we altered the design to include a fairly thicker and rounded rim at the base to ensure that it is less susceptible to damage while handling or transporting. After these changes we termed the changed design “Cup Base” to ensure it is not confused with the traditional “Concave base.

217 Caliber REX Air Rifle Slug – Specifications

The 217 Caliber REX slug is now in full production and ready for order. We are constantly updating the table below for our 217 Caliber Slugs, so please check back regularly.

217 REX ( Rapid Expanding ) Slug, 22 slug, 22 Pellet, 22 Air Rifle Slug, Accurate 22 slug, Slug Accuracy test, Slugs vs pellets

26 grain Inferno REX Slug

.217 REX Slugs – Specification table

217 Caliber REX Air Rifle slugs, 22 Slugs, 22 pellets, Accurate 22 slugs

Our intent with the 217 Caliber REX slug is not to replace existing designs. It has been built with a specific purpose – where there is a risk of damaging a backstop. ( Read through our terminal ballistic report for more detail ) Additionally, it does not make sense to pay more for a REX slug when you know you will not cause damage to anything behind your quarry.

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We will shortly publish a table that will list all the variables that we used in design and testing of our .217 Caliber REX slugs. These will include the following :

  • Air Rifle Manufacturer
  • Air Rifle Model
  • Slug weight
  • Slug Nose and Base configuration
  • Regulator Pressure
  • Velocity
  • Group size at 25m, 50m & 100m

Please feel free to let me know through our “Contact Us – Page” if you would like to see any additional information.

Most of our design and testing so far were with the following Air Rifles:

We have also tested custom fitted Lothar Walther Polygonal Barrels in some of these air rifles proving top accuracy !