Date: 25/9/2021 5:33
FLASH SALE: Get $20 Off Your Next Order of $200 or More! Use Coupon: ONLY4U20 at checkout *

*Limted time only. Some items excluded.


JSB Diabolo Exact King Heavy, .25 Cal, 33.95 Grains, Domed, 300ct

5.0 (56 reviews) Review, article, latest buzz
JSB Diabolo Exact King Heavy, .25 Cal, 33.95 Grains, Domed, 300ct

JSB Diabolo Exact, Image 1

See 2 customer imagesShare your images


List Price $22.99Save $3.00 (13%)
Pick Your Option
  • 1-year limited warranty

  • 60 day money back guarantee
  • Estimate Shipping

Add to Compare
Add to Wish list

Earn 20 Bullseye Bucks


Out of Stock

Estimated in-stock date 11-01-21

Notify me when product becomes available

  • FeatureIcon
    2020 Best Seller
  • FeatureIcon
    WARNING This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to
youTube video

See other products by JSB

Out of stock
Estimated in-stock date 11-01-2021. Place your order now for delivery priority!

  • .25 caliber
  • 33.95 grains
  • Domed
  • 300 pellets

Please note: The only difference between the original King Heavy and the King Heavy MkII pellets is the outer diameter of the skirt. This dimension on the original MKI pellets are 6.68 - 6.70 mm while the MKII pellets measure 6.58 - 6.60 mm. The appearance of the skirt or back of the pellet can vary.  

Item Code: JSB-1002534 [PY-P-1269]

See other products by JSB



Caliber.25" (6.35mm)
Ammo TypePellets
Suggested forSmall game hunting/plinking
Ammo Shape
Head Size6.35 mm
Length8.74 mm
Ballistic Coefficient0.062 A measure of the potential to retain velocity. Changes as velocity changes. A pellet or bullet with a high BC (a large number) will continue to fly much longer than a pellet or bullet with a low BC.
Muzzle Velocity885 fps

Average Customer Review

5.0 (56 reviews)
5 star
4 star
3 star
2 star
1 star
50 reviews
4 reviews
2 reviews

Create an online review

Customer images

Sort by Date: Newest–Oldest

5.0 5.0

5.0 5.0

5.0 5.0

Things I liked:

Very accurate pellets! Shooting them out of my Benjamin Kratos. I like the buy 4 tins and getting the fourth one free.

5.0 5.0

5.0 5.0

5.0 5.0

Verified Purchase

Things I liked:

I like how the pellets were packed for shipping. Pellets were very clean and uniform in appearance. The skirts appear slightly thicker than other brands I have tried. Thicker skirts should reduce possible deformation issues as well as creat a more balanced weight distribution front to back in each pellet. This should aid to stabilizing the pellet during flight.

Things I would have changed:

A screw on lid would be great.

What others should know:

I am a bench rest shooter. We strive for tight groups at distance. Having recently purchased a PCP rifle i tried several different brands of pellets with little success of holding any assemblance of acceptable accuracy. That is until I tried these JSB pellets.was able to shoot one ragged hole group at 50 yards. Using these pellets I might be competative with the rimfire shooters I compete agenst.

5.0 5.0

5.0 5.0

5.0 5.0

Things I liked:

I bought these for my circa 2006 Airforce Condor. Because the MkII pellet has a smaller skirt than the standard JSB pellet, they did not shoot acceptably in my Condor. However, these are EXTREMELY accurate in a FX Wildcat III using the STX superior liner. I get all 5 shots touching at 100 yards, shooting at 920fps. I did not weight sort them either, so they must have been very consistent weight. Velocity spread was 923 to 919 fps for 30 shots.

Things I would have changed:

Twist lid container would be nice.

What others should know:

These are ideal for airgunners who do not need slugs. I can hit beer bottlecaps at 125 yards every single shot with these. My hunting range rarely exceeds 100 yards, and these are more accurate than ANY slug I have tried in the FX rifle. The skirt on the MkII variety is smaller by a few thousandths. I would try a tin of the standard variety with the larger skirt before assuming the MkII will work well in your rifle. I found the standard JSB shoots better in an Airforce, while the MKII do much better in an FX.

+ Load More

Got a question or answer?
Log in to participate

  • TOLBERT from USA asked:

    What is the difference between MKII and regular JSB's?

    • John from USA answered:

      MKII skirt is 6.5 mm regular is 6.65 mm

  • Loren from Canada asked:

    What’s the BC?

    • Tyler from USA answered:

      Actual BC will vary depending on the velocity they are shooting out of your specific rifle

  • Nathan from USA asked:

    Will these fit in the Benjamin Marauder magazine?

    • Randy from USA answered:

      Yes, they fit mine just fine...accurate as all get out to boot!

+ Load More

Buy with confidence

Get FREE shipping on qualifying orders! Any order $150+ with a shipping address in the contiguous US will receive the option for free ground shipping during checkout. Certain restrictions apply.

Free shipping may not be combined with a coupon unless stated otherwise.

View Shipping Info

Text JOIN to 91256 and get $10 Off Your Next $50+ Order.
*By subscribing to Pyramyd Air, you agree to receive recurring autodialed marketing text messages to the mobile number used at opt-in. Consent is not a condition or purchase. Msg freq may vary. Msg & data rates may apply. Text HELP for help, Text STOP to 91256 to opt out. Reply with birthday MM/DD/YYYY to verify legal age of 18+ to receive texts. Terms of Use & Privacy Policy.