Blog: JSB Exact King Heavy Airgun Pellets - Scopes and Barrels

JSB Exact King Heavy Airgun Pellets

               JSB Diabolo Exact King Heavy .25 Cal, 33.95 gr - 150 ct (Eng)


       The new heavy weight when it comes to .25 JSB pellets, weighing in at 33.95 grains. The JSB King Heavy .25 caliber pellet was developed due to the request of many airgunners with higher power PCP airguns looking for a little heavier pellet. The skirts on these are rather large so if you're having trouble with your gun loading them, pick up the King Heavy MKII instead.


JSB Exact King Heavy Pellets - .25 x150. The first JSB Exact pellet in cal.25. Carefully designed, precisely produced and hand picked quality control ensure supreme accuracy. A middle-ranged weight ensures (it is JSB) is very keen to the demands of the World, and it feels as though they are especially in-tune with the US market specifically. The Czech Republic company has been manufacturing pellets for many years, and they began specifically with the 10-Meter match gun market. Over the course of business, they have added and included so many types of sporting pellets, hunting pellets, and more. Many years of hard work and dedication to detail have earned JSB a reputation for building quite possibly the best pellets around! When they jumped into the Quarter-bore market with the JSB King .25, they were met with huge success. As the market continued to grow in the .25 caliber, the power levels began to rise as well. So what have we come to expect from JSB? They respond with yet another great pellet…the King Heavy .25 at a dense 33.95 grains!


                                    King Heavy (left) vs standard King (right)


The JSB King Heavy .25 pellets are all around good looking pellets! They have a long, thick waist, with very little taper. At a glance, they resemble a cylindrical pellet like the old Sheridan .20’s. The skirts are good and solid, which will help the soft lead composition hold up with moderate use. The head is a shallow round nose, and is likely the best design possible, knowing the extent of testing JSB would have performed prior to committing to this profile! We have the King Heavy pellets in the larger 150 count tins, and they come safely packaged with foam liners on top and bottom of each tin for added security and support.                                                                                    



In testing, accuracy is what accuracy always will be…hit or miss! No pellet will ever be the best in all barrels, and no pellet will shoot with accuracy guarantee. As with most  JSB’s, we find they are more consistently the best pellet tested out of many airguns. The same held true with the King Heavy .25’s. Heavy hitters like the FX Royale 500 or the Daystate Air Wolf Extreme did surprisingly well with these new pellets. Velocity (of course) decreases, but overall power increases and BC gets better with these King Heavies! We tested the FX Wildcat .25 for fun and got these results:

King 25.39gr = 910 fps Average = 46.7 ft/lbs

King Heavy 33.95gr = 805 fps Average = 48.9 ft/lbs


As you can see, the power level of the rifle increased by over 2 ft/lbs, and the added weight retains the energy better down range. Also, due to the lower velocity, the pellet had a noticeably quieter report when exiting the rifle! All these features add up to great things for hunters!


JSB Diabolo Exact King Heavy Features

Manufacturer:           JSB

Caliber :                    0.25 cal

Ammo Type :            Pellets

Ammo Weight :         33.95 gr

Pellet Shape :           Domed

Pellet Quantity :        150

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