How fast can an airgun shoot? – Part 1
by B.B. Pelletier
Good morning, everyone. Although I didn’t respond to most of you yesterday, I did read what you said. I’m in the process of asking for some more permanent guest bloggers, and we’re looking into the “Recent Comments” widget. At this point we think we have to write the code ourselves. Does anyone know of a similar widget that already exists?
I’m sorry if I sounded like a whiner yesterday, and I hope I didn’t scare my old Airgun Letter readers into thinking I was abandoning them again. I assure you, nothing of the kind is in the works.
But there IS something very exciting in the works, and I will tell you about it in this blog a week from today. On that day, Thursday, Jan. 15th, which is the first day of the SHOT Show, I will be attending the Airgun breakfast that Pyramyd Air is hosting in Orlando. A huge announcement will be made at the breakfast at around 7:45 a.m. Eastern time. I am scheduling that day’s blog to publish at the same time, rather than the normal 6:30 Eastern time it now publishes. You’ll hear the news in the blog at about the same time it is announced to the airgun industry. I will say no more about this until that morning.
Now, let’s get to today’s report.
Let me begin by saying that I do not know exactly how fast an airgun can shoot. But I have done some testing and I have observed some things, so I’m at least qualified to talk on this subject from my personal experience.
Why am I waffling so? Because this topic is a hot button in the airgun community. There are endless discussions on forums, and many “experts” present their data and formulae to prove this or that point. The ones I enjoy most are the guys who admit that they don’t own a chronograph or even have access to one, but they offer scientific “proof” that it’s physically impossible for an airgun pellet to exceed the sound barrier when powered by air only. They may actually have a minor point, since the Cardews (The Airgun From Trigger to Target) proved that all spring-piston guns over a certain velocity diesel with every shot, but that doesn’t take pneumatics into account. I plan to.
I’m going to share what I know for sure, and you guys can take it from there. I’ll also write a short article on this subject for the Pyramyd Air website and accompany it with a long video of Dennis Quackenbush and me doing some testing at the 2008 LASSO big bore shoot.
I’ll give all the support I have for what I tell you, but I’m not going to postulate why things are the way they are. My science background is not strong enough to support that discussion [Jane Hansen–Are you reading?], so I’ll just share the actual data I’ve seen and collected.
This discussion probably started back in the early 1970s, when the 800 f.p.s. “barrier” was first broken. Maybe it was broken before then, but I know for certain that the long-stroke FWB 124 in .177 caliber could reliably exceed 800 f.p.s. with some light pellets, and the airgun community treated it as a BIG DEAL.
No doubt Vince is wondering if I’ve lost my mind by rambling on about 800 f.p.s., but the 1970s were a time when that was considered big stuff. And then 1,000 f.p.s. was exceeded in the early 1980s, and a few years later Diana topped 1,100 f.p.s. with their new sidelevers. Finally, Ivan Hancock built the Venom Mach I, a breakbarrel spring rifle that exceeded the speed of sound…and everything was up to date in Kansas City.
For a decade, the goal for a powerful smallbore airgun was to exceed 1,100 f.p.s. and go supersonic, if possible. Before you tell me, I know the sound barrier can also be below 1,100 f.p.s., but it was always held separate from the chronograph readings, so I’m reporting it that way.
In 1999, Gamo decided we hadn’t gone far enough, and they brought out the Hunter Hurricane 1250. That’s right, it was supposed to shoot 1,250 f.p.s. Well, as I was writing The Airgun Letter at the time, I decided to test it. Who did Gamo think they were, making a claim like that?
The thing is, their rifle REALLY DID shoot that fast. Or at least the one I tested did. Those where the days before we had the lightweight trick pellets, so they had to get there with an RWS Hobby, which weighed 6.9 grains back then. I saw several shots from my test rifle go faster than 1,250 f.p.s., and the fastest one went 1,254 f.p.s. The velocity race went into overdrive.
That was the first hyper-velocity pellet rifle I saw that failed to live up to the hype. I tested it for you in this blog.
Stop right there!
In my test, the Hunter Extreme went up to 1,395 f.p.s. Not bad at all, but a far cry from 1,600 f.p.s. To add insult to injury, Gamo now laser-engraves the expected velocity on the compression tube of the rifle, and there it says to expect 1,650 f.p.s. I got 1,395 f.p.s. I asked you readers to give me your velocities and nobody did. Other airgunners I contacted told me their Hunter Extremes went as fast as 1,425 f.p.s. Again, not too shabby, but not 1,600 f.p.s., either.
Gamo ENGRAVES the expected velocity on the steel compression cylinder of the Hunter Extreme. In all my testing and correspondence with other Hunter Extreme owners, this number has never been approached, except when the rifle detonates some fuel.
This is the average velocity I saw from the Hunter Extreme shooting Gamo Raptor PBA pellets. The top speed I recorded was 1,395 f.p.s.
Just as I was recoiling from that test, Benjamin brought out the Super Streak, which they advertise to shoot up to 1,500 f.p.s. That threw me back into the testing mode again, and I came up with a top speed of 1,323 f.p.s. with Raptors. Nowhere close to 1,500 f.p.s. In fairness, the Crosman Silver Eagle pellet line was new about the same time, and I didn’t try them with this rifle. The hollowpoint is only 4.8 grains and has been beating the Raptor in velocity tests, so it might have boosted the number a little. But not enough.
While I was still on the ropes from the Super Streak, RWS Diana brought out the 460 Magnum–a rifle that was advertised to reach 1,200 f.p.s. in .177 (though one airgun internet retailer has it listed at 1,350 f.p.s. for some reason). Have you noticed anything strange yet?
What’s strange about this trend?
What’s strange is that the top velocities advertised are FALLING, rather than increasing. Gamo still advertises 1,600 f.p.s., but Benjamin, who came out later than the Hunter Extreme says their hyper-velocity gun is 100 f.p.s. LESS. And now the RWS Diana 460 Magnum drops another 300 f.p.s in their claim. And it’s an important 300 f.p.s., because some airguns really can go 1,200 f.p.s. I actually got up to 1,155 f.p.s. from the test 460 shooting Raptors. I point this out without comment.
Then why do they advertise 1,600 f.p.s.?
They advertise it because the rifles can do it. With a little oil down the transfer port, the Hunter Extreme can go faster than 1,600 f.p.s. It takes a small explosion to go that fast, or at least in my experience there has never been a test rifle that went that fast without a violent detonation. And therein lie several problems.
Problem 1 – blown seals
Back in prehistoric airgun times, Weihrauch had the Barakuda EL-54 ether-injected breakbarrel rifle that was built to propel a 15.3-grain .22 caliber round lead ball to 1,000 f.p.s. H&N even made a special 21-grain lead diabolo pellet for the rifle they called the Baracuda. Later, Beeman called it the Kodiak. Read about that rifle here.
The trouble was that with all the explosions, the Barakuda rifles couldn’t keep their leather seals from blowing. It was an idea ahead of its time.
Problem 2 – it’s not an airgun
The definition of an airgun varies by country. The U.S. is pretty open as far as power and velocity go, but a firearm cannot be an airgun.
Who said anything about a firearm?
Well, to paraphrase the legal definition of a firearm, it’s “any device that propels a projectile or projectiles by means of an explosion.”
Yes, certain springers achieve super-high velocities, but to do so seems to take an explosion. If that’s true, we’re not talking about airguns anymore.
The gun that fired the .22 Daisy VL caseless cartridge used a spring-piston powerplant to heat the air that ignited the compound on the base of the bullet. That compound then burned rapidly enough to seem like an explosion. Therefore, the Daisy VL system was considered a firearm
Okay, there’s some food for thought. In the next part, I’ll tell you what Dennis Quackenbush decided to do about it, and I’ll also share my experience of the fastest true airgun shot I ever witnessed.