Highest Velocity Blowback Action pistol Part 1

Highest Velocity Blowback Action pistol Part 1

And the fastest BB

By Dennis Adler

The fastest gun in the running for last year’s Replica Air Pistol is ready to find the best BB for velocity and accuracy. Keep reading, you might be surprised which of the steel BBs above delivered the highest velocity. As for the Gamo lead round BBs, they are there to make a point about the history of BBs and the use of lead shot.

I have often said that velocity isn’t everything in a blowback action CO2 pistol, but when you have a high velocity, blowback action CO2 pistol like the Umarex Glock G19X, why not make the most of it? The G19X was the one new model from 2019 that had no peers when it came to sending a steel BB downrange at well over 350 fps, actually an average of 376 fps with the highest velocity right around 380 fps, which is 20 fps over the factory rated 360 fps. The next highest speed clocked with Umarex Precision steel BBs was 379 fps, followed by 377 fps, 376 fps four times out of 10, and a low of 372 fps, which soundly beat any other new model from 2019, including the Replica Air Pistol of the Year which was sending steel BBs downrange at around 300 fps average. What kept the G19X from winning was the non-functional right side slide release, and no bonus point for field stripping. That was enough to keep it from earning 50 points and knock it out of contention. It was a small but tough crowd for last year’s top gun title.

Here’s the points recap from the G19X review:

Authenticity 1 to 10:  9 (Excellent copy of Gen5 9mm except for right side slide release)

Ingenuity of the design 1 to 10: 10 (Excellent fit and FDE finish to match 9mm model)

Ease of use 1 to 10: 10 (Easy to load BBs and CO2 with new seating cap tool)

Performance 1 to 10: 10 (Highest velocity of any blowback action model)

Accuracy 1 to 10: 10 (Shoots to POA with white dot sights, best group 0.625 inches)

Bonus points: 0

Total Points: 49

It is one good looking air pistol. The G19X (in either 9mm or .177 caliber) does a great job of giving production model Glocks a custom look with its re-contoured Gen5 slide and frame and distinctive coyote tan finish. This also makes it a standout as a CO2 model. The fact that it develops the highest velocity of any new blowback action model from last year, is just the unexpected bonus, and proof that you can have robust CO2-driven recoil, and still send shots downrange at well over 350 fps.

If we focus just on velocity, fit and finish, and accuracy, and overlook the key Gen5 features not offered on the G19X CO2 model, i.e., right side slide release and interchangeable backstrap panels, and the air pistol’s firing system design which precludes field stripping, you have a Glock understudy for a Compact Glock 19 pistol that is otherwise authentic to the design of the 9mm model, and ideal for learning the fundamentals of Glock handling. It is also, at the moment, (and the moment is fleeting with a new Gen5 CO2 model on the horizon for 2020), the best choice in a high-velocity blowback action air pistol. So, assuming you felt the same way and purchased a G19X, let’s see what the fastest blowback action pistol can deliver with the best .177 caliber (4.5mm) steel BBs.

One other advantage to the G19X is a new seating screw wrench that makes it easier to turn down the cap and pierce the CO2 cartridge. This shot also provides a clean view of the warning info that is placed on the bottom of the triggerguard with the caliber markings and proof mark on the dustcover.

BB variance

As those of you who follow BB gun history know, a “BB” was originally a measurement for lead shot used in shotguns (which ranged in 15 sizes from “F” which was .22 inches all the way down to “No.9” which was a scant .08 inches, “BB” being the fourth size down the scale with an average measurement of .18 inches or 4.57mm (later to become .177 or 4.5mm for airguns, so “BB” in name only as “BB” shot is still .18 inches, 4.57mm). For use in early spring piston air rifles, which were perfected between 1886 and 1888 by the Markham Air Rifle Company and Plymouth Air Rifle Company both located in Plymouth, Michigan, “BB” size birdshot was the chosen ammunition. Being a common size used in shot shells it was readily available. The Plymouth Air Rifle Co. changed its name to Daisy Manufacturing Co. in 1895, and in 1900 standardized the lead shot used for their air rifles to a bore diameter of 0.175 (4.4mm) and began using lead shot made exclusively for air rifles and sold by Daisy. Standard “BB” birdshot was (and is still available) but steel BBs wouldn’t come along until the 1920s, when Daisy (and other air rifle manufacturers) slowly began the transition. Steel BBs were originally manufactured by The American Ball Company of Minneapolis, which had started selling them under the Bulls Eye brand. However, this was a sideline for American Ball, which primarily manufactured ball bearings, not birdshot, and they were not keeping steel BB tolerances close enough. Very soon, the variance in sizes among Bulls Eye BBs were beginning to break Daisy air rifles. An oversized steel BB was not malleable like lead and it could jam in the Daisy, or worse, split the shot tube, which was not as hard a metal as the steel used for the BBs. Daisy solved the problem in 1928 by forging a relationship with American Ball to manufacture precision steel BBs that would be exclusively distributed by Daisy as Bulls Eye Air Rifle Shot. It worked out so well that Daisy bought the American Ball Company in 1939.

This view of the locked open slides shows how the G19X CO2 nozzle literally rests against the back of a chambered BB. This is part of the design that helps optimize CO2 use and increase velocity by more than 50 fps over other blowback action models including the new Umarex Glock Gen4 CO2 model. The loss of field stripping capability and full slide retraction is the biggest tradeoff to get more performance out of the G19X.

Today, just about every airgun manufacturer has its own line (or brand) of steel BBs, however, lead BBs are still manufactured for airguns, by Gamo, for exampe, but mostly for guns with rifled barrels. There is also H&N Smart Shot, which is a copper coated lead BB safe for use in blowback action smoothbore pistols, but the majority of BBs used in smoothbore airguns today are steel, which brings us to the choice of BBs to be sent down the barrel of the G19X in our search for the highest velocity and accuracy combination.

Match, Precision, Anodized and Coated      

What sets some of the top rated steel BBs apart is the quality of the finish. Daisy Match Grade are precision ground un-plated chromium steel with a mirror like finish, and are generally more consistent in weight and size. Daisy Match Grade 5.1 gr. steel BBs are also more expensive at $7.99 for 1050 vs. Daisy Premium Grade Precision Max, offering 4000 zinc plated BBs for the same price. Comparatively, Umarex Precision 5.1 gr. steel BBs (which are close in finish to the Daisy Match Grade) cost $5.00 for 1500. (All prices are MSRP and are usually discounted).

Plating plays a role even though Daisy does not plate its Match Grade BBs. Hornady Black Diamond, for example, retails for $6.99 and gives you 1500 high quality black anodized steel BBs which, with some blowback action pistols, will give you a little extra velocity even though they are also 5.1 gr. Of course, you can go for quantity like Remington, which supplies 6000 solid plated steel BBs in a heavy plastic bottle (also good for use to exercise your wrists) for $9.99, but the point is, how much difference does a more expensive Match Grade steel BB, like the Daisy, make against Umarex and Hornady BBs?

Getting back to the H&N Smart Shot with 7.4 gr. copper coated lead BBs, you sacrifice a chunk of velocity because of the extra 2.3 grains in weight, but gain the capability to shoot at reactive steel targets. For use in the G19X, which is shooting faster than factory specs with steel, you’re still going to get 300 fps with the lead rounds.

This is the target to beat, the G19X with Umarex Precision steel BBs fired off hand from 21 feet. Best 5-shot group measured 0.68 inches.

Through the chronograph   

The Umarex steel BBs have already been tested and proven to deliver velocity and accuracy with the G19X clocking an average of 376 fps and delivering a best group fired off hand from 21 feet of 0.68 inches.

Today, we are just going for comparative speed with Hornady Black Diamond black anodized, Remington plated, Daisy Precision Max zinc coated, and Daisy Match Grade.

As is sometimes the case, the Hornady Black Diamond does not give you any higher velocity and the G19X averaged 370 fps, with most at 365 fps and one at 378 fps, still just a hair slower than Umarex in the G19X. The Remington faired just slightly better at 372 fps average, and again with most in the 365 to 370 fps range, so the Umarex steel BBs are still the best match thus far for the Glock. Breaking into the Daisy Precision zinc coated, the average went down to 368 fps, with most between 360 and 365 fps and a high of 370 fps. Now, going to the more costly Match Grade Daisy, which is un-plated chromium steel with a high polish, the average velocity clocked in at an impressive 375 fps (15 fps faster than factory specs for the G19X), with the majority of shots flip flopping between 374 and 376 fps, but no better than the Umarex on overall speed.

The top average velocity from this first BB test was within 1 fps between the Umarex Steel BBs and the more costly Daisy Match Grade. The question is, can the Match Grade outshoot the Umarex Precision from the same gun at virtually the same velocity?

In Part 2 we will find out if the higher-priced Daisy Match Grade BBs can beat 0.68 inches at 21 feet established with the G19X and Umarex Precision steel BBs.

A word about safety

Blowback action airguns provide the look, feel and operation of their cartridge-firing counterparts and this is one reason why they have become so popular. Airguns in general all look like guns, blowback action models more so, and it is important to remember that the vast majority of people can’t tell an airgun from a cartridge gun. Never brandish an airgun in public. Always, and I can never stress this enough, always treat an airgun as you would a cartridge gun. The same manual of operation and safety should always apply.

2 thoughts on “Highest Velocity Blowback Action pistol Part 1


  1. My experience has been that higher velocity I airguns translates to better accuracy out past 21 feet. It also does better on reactive targets. I would take pints away from the Glock for the lack of a functioning ambi slide release and a non reversible mag release. I have a gen 5 model 19 9 mm Glock and found the lt side’s mag release to be uncomfortable and obstrusive for a left handed shooter, so I reversed it. The replica 19x is not a true Gen 5 pistol by lacking these features. Another lazy job by Umarex


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