Posts Tagged ‘velocity’

AirForce Escape: Part 3

by Tom Gaylord, a.k.a. B.B. Pelletier

Part 1
Part 2

AirForce Escape rifle
The AirForce Airguns Escape precharged pneumatic air rifle is a powerful new survival rifle in both .22 and .25 calibers.

Last time we looked at the accuracy of the AirForce Escape at 50 yards. I shot the rifle on low pressure and a low power setting on that day to see what it could do. You may remember that at 50 yards, I got a best 5-shot group with JSB Exact King pellets that measured 0.594 inches between centers. That’s great for a .25-caliber PCP, but I know it left some of you wondering what the rifle can do at its maximum power. Today, we’ll look at that.

The heaviest .25-caliber pellet I have is the Eun Jin pointed pellet, which weighs 43.2 grains. So, it’s a little heavier than the standard bullet of a .22 Long Rifle cartridge. We know from testing that this pellet leaves the muzzle at up to 1010 f.p.s., generating 97.88 foot-pounds of energy.

I also had some Eun Jin domed pellets to test. At 35.8 grains, they’re lighter than the pointed pellet but might be accurate enough to make a difference. As long as I’m testing, I thought why not test them, too?

AirForce Escape rifle Eun Jin pointed and domed pellets
These are the 2 pellets used in today’s accuracy test. The pointed pellet weighs 43.2 grains, and the dome weighs 35.8 grains.

The wind had just started to pick up at the range. I had finished testing the Benjamin Marauder with synthetic stock and shifted to the Escape because I felt the power of the gun and weight of the pellet wouldn’t be affected by this wind nearly as much as a smaller pellet moving at lower speed.

Max power
The first thing I tried was the heavy Eun Jin pellet on max power and with a max power setting on the gun. The first 2 pellets went through the same holes at 50 yards, and I thought I was on to something. Then, shots 3 and 4 moved 2 inches to the right but also landed in a single hole. Shot 5 then landed an inch to the left of the first 2 shots, giving me a 5-shot group that measures 2.478 inches across the widest centers. While that is adequate accuracy for larger animals at 50 yards, it wasn’t as good as I’d hoped it would be.

AirForce Escape rifle Eun Jin pointed pellet group 1
Five Eun Jin pointed pellets on maximum power with a 3,000 psi fill at 50 yards. The group measures 2.478 inches between centers, but look how they landed. The first two are left of the pellet, the next 2 are to the right of the dime (in the same hole) and pellet 5 is all the way over to the left.

I remembered that there are 10 good shots on a fill of the Escape’s small 213cc reservoir, so I shot the next 5 pellets at a different target. The scope wasn’t adjusted. The reservoir pressure at the start of this string was about 2,600 psi. This time ,all 5 went into 1.622 inches. That’s a significant improvement. According to the velocity test data, these shots ranged between about 71 and 82 foot-pounds.

AirForce Escape rifle Eun Jin pointed pellet group 2
By starting with less reservoir pressure, the group tightened significantly. These 5 shots went into 1.622 inches between centers at 50 yards.

I was satisfied with the results of this heaviest pellet, but I’ve never gotten the best accuracy with pointed pellets. I felt I might be at the limit of this pellet’s performance. Time was passing and the wind was building, so I moved on.

The lighter domed pellet remained to be tested. On max power with a 3,000 psi fill, I got several open 5-shot groups that all hovered around 2 inches. While that’s okay, it isn’t what I wanted. Then, I shot a couple groups with the power set to max and the starting air pressure set at 2,600 psi. The only reason I did it that way was because of the results of the heavier pointed pellet I’d just tested. And that’s where the magic happened!

The first 5-shot group on this setting (power set on max, starting fill pressure at 2,600 psi and shooting the 35.8-grain domed Eun Jin) measures 1.177 inches. Four of those shots are in 0.555 inches! That’s fantastic! I don’t have the velocity data for this pellet on that setting, but I’ll venture a guess it’s producing around 60-70 foot-pounds.

AirForce Escape rifle Eun Jin domed pellet group 1
Now, we’re cooking! Five Eun Jin domes went into 1.177 inches at 50 yards, with 4 of them making a 0.555-inch group! This is fantastic, but can I do it again?

Like you, I wondered if this single group was just a fluke, so I filled the reservoir to 2,600 psi, again, and shot a second group. This time, I put 5 into 1.089 inches. Three of those pellets are in 0.214 inches. If you overlay those 3 pellets on top of the other group, they all go to the same place!

Air Force Escape rifle Eun Jin domed pellet group 2
Here’s the miracle I was talking about. Same starting air pressure, and 5 pellets went into 1.089 inches. Three of them are in 0.214 inches and in the same place as the 4 pellets from the last group. This is significant!

What I’m saying is that somewhere around this power setting and fill pressure, there’s a super sweet spot the Escape loves with this domed pellet. By spending more time refining the fill pressure and by adjusting the sights for this combination, the Escape will become a tackdriver. It doesn’t get a lot of shots like this, but remember — this is a survival rifle. You want one shot — one kill. I think this gives that to you!

I could continue to refine my pressure settings with this pellet, but I don’t think I have to. I’ve now shown you 2 different ways the AirForce Escape can make very small groups at 50 yards. If you’re looking for a powerful air rifle to do some serious hunting, you should consider this one. I think Ton Jones and John McCaslin both have reason to be proud of their creation.

What’s next?
I was prepared to exchange barrels at this point and try the .22-caliber Escape, but I think I’ll let that slide for now. If I’m any judge, most buyers are going to get the .25-caliber Escape. Once they see these results, I expect they’ll do similar tests. Therefore, I plan to switch over to the EscapeUL next. That’s the ultralight rifle that has an 18-inch barrel. I’ll give you a combined introduction and velocity/power report, followed by a range test like this.

Benjamin Marauder PCP .177-caliber air rifle: Part 5

by Tom Gaylord, a.k.a. B.B. Pelletier

Part 1
Part 2
Secrets of loading the Benjamin Marauder magazine
Part 3
Part 4

Benjamin Marauder
Benjamin Marauder

Before I begin today’s report, I have some news about Leapers’ scopes for blog reader Kevin. He wondered what the status was on the new Bug Buster scopes with the thinner reticle lines, so I asked Leapers for an update on that plus a couple other scopes that will be coming out soon. The new Bug Buster is apparently coming to market very soon. It’s impossible to say for sure exactly when, but the next 60 days sounds about right. Leapers will be sending me a sample to test for you, so I’ll do a report on it. But I also learned that they have several full-sized scopes that have parallax correction down to 5 yards. That’s almost in the Bug Buster range. They’re sending me some samples right now, and I’ll report on them for you.

The scout scope with the 11-inch eye relief is due to hit the market some time in September. This is a scope for your pneumatics, like the Benjamin 392, but it’ll also be ideal for Mosin Nagants and some lever-action centerfire rifles.

The bubble level scope is expected out around the Christmas holiday timeframe. This is the one I’ve been waiting for because it should be a long-range shooter’s dream. I’ll have more as I test the scopes they’re sending. Now, to today’s report.

This will be especially important to those who are new to precharged airguns and are trying to understand how to adjust their rifles for optimum performance. It should clear up some things for you about velocity, accuracy and tuning a PCP.

In the third report, I shot the Benjamin Marauder for accuracy at 25 yards. I shot 8 different premium pellets to see if 1 or 2 of them stood out. One did — the Crosman Premier 7.9-grain dome — also known as the Premier Lite. In case you aren’t aware, I link the names of evey pellet (the first time it appears) in the report to the specific pellet used. So, when I say Crosman Premier Lite, I’m referring only to the Premiers that come packed in cardboard boxes. Premiers that come in tins may work well, too, but I didn’t test them.

The Premier Lite stood apart from all the other pellets by making a 5-shot group that measured 0.139 inches between centers at 25 yards. And 10 Premiers went into 0.285 inches. The next closest pellet grouped 5 into 0.316 inches, which is more than twice as large as the 5-shot Premier target. So, today I shot only Premier Lites. After filling the rifle to 3,000 psi, I fired six shots to wake the valve up and exhaust some air to get on the power curve (the gun needed 2 shots before the velocity climbed up to the optimum range in the last test following power adjustment), then I shot 3 10-shot groups. The results were very informative!

Group 1
The first group measures 0.452 inches between centers. There are 2 shots that aren’t in the main group. The third shot I fired strayed over to the left, where it stands apart from the main group. And the sixth shot fired went high. You can see it above the main group. All the other 8 shots went into a group measuring 0.183 inches between centers. There’s a strong temptation to call these 2 shots as fliers, and they may well be fliers — but let’s wait to see the other groups.

Menjamin Marauder Premier Lite Group 1 25 yards
Ten Premiers at 25 yards went into 0.452 inches. Shot 3 went wide to the left, and shot 6 went high. The other 8 shots made a nice round group.

After this group, I adjusted the scope 2 clicks to the right and fired a second group. This one has no obvious stray shots, but the groups measure 0.397 inches between centers. When the power was set higher the best 10-shot group of Premiers measured 0.285 inches That’s a big difference. Incidentally, in case you’re wondering, the Centerpoint 8-32X56 AO scope I’m using does not stick after reticle adjustments. So, there’s no need to bump the scope or shoot several shots before the adjustments take affect.

Menjamin Marauder Premier Lite Group 2 25 yards
Ten Premier Lites in 0.397 inches at 25 yards. No obvious wide shots, but a group that’s larger than what was shot on higher power. This is the best group of this test.

I then adjusted the scope 3 more clicks to the right, for a total of 5 since starting the session. Now, I fired 10 more shots. This time, the group measured 0.480 inches between centers — the largest group of this session. You can see 2 shots at the upper left of the group that are obviously not with the remaining 8 shots. The 8 shots that stayed together measure 0.181 inches between centers and are in a very round group.

Menjamin Marauder Premier Lite Group 3 25 yards
Ten Premiers in 0.480 inches at 25 yards. Again, there are two wide shots to the upper left. The main group is nice and round — and small!

Analysis
What we have here are 3 groups — all shot on the power curve of the rifle that now averages about 886 f.p.s., rather than the former 1,015 f.p.s. I told you earlier that I thought a velocity of around 900 f.p.s., give or take, would be ideal for my purposes; and I thought it would give several more shots per fill. We did see those extra shots in Part 4. There were 45 good shots at the lower velocity compared to 31 good shots at the higher velocity.

If I’d been right about the lower velocity not making any difference in performance, everything would be fine. But from what I see here, everything is not fine. The 3 groups fired at the lower velocity were all much larger than the one 10-shot group shot at the higher velocity. And 2 of the 3 groups have 2 stray shots in them. They’re not called fliers in the sense that I did anything to make them go astray. They just went where they went.

My thoughts are that the rifle doesn’t shoot Crosman Premier Lites as well at 886 f.p.s. as it did at 1,015 f.p.s. I think I need to increase the velocity and see if I can get the groups to shrink again. I’m thinking 950 f.p.s., give or take. That way, I’ll still get a few more shots than I was getting when the average was over 1,000 f.p.s., and hopefully the groups will shrink back to the 0.300-inch region for 10 shots.

Sanity check
Before you start commenting, take another look at that dime against these 3 groups. They aren’t that bad! But we’re now down in the minutia, looking for perfection. That’s what I meant when I said this day was especially important to those who are trying to understand and tune their PCPs.

Benjamin Marauder PCP .177-caliber air rifle: Part 4

by Tom Gaylord, a.k.a. B.B. Pelletier

Part 1
Part 2
Part 3
Secrets of loading the Benjamin Marauder magazine

Benjamin Marauder
Benjamin Marauder

Today, we’ll start learning how to tune the .177 Benjamin Marauder we’re testing. An owner can do two things to his rifle. He can adjust the power (which is the velocity) and he can adjust the maximum fill pressure the reservoir will accept. The power adjustment is straightforward, and I’ll get to it in a moment. The fill pressure is more obscure. Unless you have a good reason to adjust the maximum fill pressure, you should leave it set to 3,000 psi because that will give the greatest number of shots. I’ll adjust the fill pressure in a future report. Right now, we’re looking at just velocity.

The velocity is controlled by a screw that impedes the airflow through the transfer port. The screw enters the port from the underside and goes across the port, blocking a percentage of the air that’s trying to flow through. Since the valve is open only for a short time, this blockage is effective. We’ll see how effective today. First, though, we need to know where the rifle is now.

To get to the adjustment screw, the barreled action is removed from the stock. The adjustment screw is on the right side of the pressure tube, ahead of the trigger unit. There’s a locking screw above the adjustment screw, and both are found deep inside a threaded hole.

Benjamin Marauder adjustment screw

The power adjustment screw is located on the right side of the pressure tube ahead of the trigger.

 

Benjamin Marauder adjustment screw in rifle
The power adjustment screw is deep inside a threaded hole — beneath a locking screw of the same size.

Benjamin Marauder locking screw
The locking screw is a small headless Allen screw.

I filled the rifle to 3,000 psi and started shooting Crosman Premier 7.9-grain pellets. We already know how accurate they are in this rifle, now let’s see how many good shots I get from a fill.

Benjamin Marauder pressure gauge
When the carbon fiber tank gauge read 3,000 psi, this is what the Marauder gauge looked like. That’s pretty close!

Shots   Shots
1-20     21-40

1014    1018
1014    1016
1020    1014
1018    1012
1019    1014
1020    1008
1026    1009
1021    1003
1026    1004
1023    1002
1028    1002
1028     997*
1029     993
1028     990
1028     991
1026     986
1027     986
1021     988
1025     981
1021     976

* Off the power curve at shot 32.

I rate this as 31 good shots because I’m accepting a 30 f.p.s. velocity spread. Since the high was 1029 f.p.s., the low would be 999 f.p.s. You can set this up any way you like, but you do see that the gun is definitely declining in velocity after the 31st shot. I would say the gun has 3 good magazines on a 3,000 psi fill with this setting.

Crosman advises in the owner’s manual to turn the power adjustment screw all the way in (clockwise) until it stops and to record just how many turns it took. Then, you’ll know where the gun was when you began; and if you ever want to return to that power, you can.

My rifle had 2-1/3 turns on the adjustment screw, as it was set. I left it all the way down, which is as restricted as it gets, and I filled the rifle to 3,000 once more. Next, I started firing the rifle and adjusting the screw after every 2 shots, while recording the velocity with the same Premier pellets.

Lowest power
424
424

Screw 1/3 turn out
525
527

Screw 2/3 turns out
655
657

1 turn out
776
779

1-1/3 turn out
871
856

1-2/3 turns out
891
896
895
897
895

That was where I wanted to be, so I stopped adjusting. I locking down the screw on the adjustment screw and put the barreled action back in the stock. Then, I filled to reservoir to 3,000 psi and started shooting another string.

Shots  Shots
1-25    26- 49

866     897
867     896
877*   892
870    891
874    890
877    889
886    892
887    888
886    884
881    887
880    881
887    883
884    878
884    879
891    877
889   876
892   876
890   874
890    870
893    870
898** 869
895    868***
898    866
897    865
897

* First good shot.
** Fastest shot
*** Last good shot

Using a velocity variation of 30 f.p.s., the same as for the first string, the fastest shot went 898 f.p.s., so the slowest acceptable shot went 868 f.p.s. There are a total of 45 good shots in this string by that criteria.

But notice that the first 2 shots were slightly below the acceptable range. That’s because 3,000 psi doesn’t work perfectly with this velocity. This is an example of how the fill pressure can also change with the velocity you select. So, the power screw adjustment shown in this report is not independent of the fill-pressure adjustments. It worked out so close this time that we can overlook the 2 slow shots at the beginning of the string; but if you try for a lower velocity average, that will probably change.

This test also gives a good sense of how the velocity average affects the total number of available shots. We went from 31 to 45 good shots by clipping a little more than 100 f.p.s. off the average velocity we would accept. And when you look at the average we’re now getting, which is somewhere around 886 f.p.s., you see that we still have a lot of velocity for serious work such as hunting. The question becomes: Which would you rather have…3 magazines of shots per fill or 5?

Noise
As long as the velocity was down below 750 f.p.s., the rifle was incredibly quiet. After it got above that number, it didn’t seem to change much between 750 and 1,000 f.p.s.

Summary
It was very straightforward to adjust the Marauder’s power, as you can see. The stock does have to come off, but it isn’t hard to do. Once you’re done, it goes back on just as easily. This isn’t a rifle that invites constant velocity adjustment. You set it and forget it, so the stock removal poses no real problem.

Benjamin Trail NP pistol: Part 6

by Tom Gaylord, a.k.a. B.B. Pelletier

Part 1
Part 2
Part 3
Part 4a
Part 4b
Part 5

Benjamin Trail NP pistol
Benjamin’s new Trail NP breakbarrel pellet pistol, with cocking aid removed.

We’re certainly getting a good look at the Benjamin Trail NP pistol! While the title says this is Part 6, it’s actually the 7th report because Part 4 was so large it had to be broken into two parts.

Let’s look at the performance of the pistol after break-in. This test pistol has been shot so much that it’s now broken in, so today we’ll look at the velocity. Crosman says in the owner’s manual that the pistol needs several hundred shots before it’s fully broken-in, and this gun certainly has that many shots through it.

They also say the gun will become quieter after a break-in, and the test pistol is certainly quiet now. Apparently, some guns have detonated and surprised their owners, so Crosman is being conservative in its explanation. The test Trail NP pistol has never been very noisy.

I’ll report the velocity of each pellet before and after the break-in period, so you can compare them.

RWS Hobby
The first pellet I tested was the 7-grain RWS Hobby. It’s normally the fastest lead pellet in almost any airgun.

RWS Hobby pellets

Crosman SSP hollowpoint
The Crosman SSP hollowpoint is a 4-grain, lead-free pellet that’s shaped like a wadcutter but with a deep hollow point. Being so light, it’s a real speed demon.

Crosman SSP hollowpoint pellets

Crosman Powershot Penetrators
Crosman Powershot Penetrators are synthetic-jacketed pellets that have a metal core. They weigh 5.4 grains and loosely fit the bore of the Trail NP pistol.

Crosman Powershot Penetrator pellets

Crosman SSP pointed
Crosman’s SSP pointed pellet is another 4-grain, lead-free pellet. You’d expect it to have about the same performance as the SSP hollowpoints, but this pellet isn’t sized as well as the hollowpoint. Consequently, they fit the bore variably, which affects the velocity.

Crosman SSP pointed pellets

JSB Exact RS dome
The last pellet I tried was the JSB Exact RS dome. It weighs 7.3 grains and fits the bore loosely.

JSB Exact RS domed pellets

So there you have it. All 5 of the pellets shot slower after the break-in, and all but one had more consistent velocity spreads. Clearly the Benjamin Trail NP pistol does break in as the company states in the owner’s manual.

This report has been a look into the performance of a spring-piston air pistol as it breaks in. We’ve seen the way to maximize the accuracy of the airgun, and we’ve learned how to overcome the too-tall front sight post. I hope this experience has been of benefit to the new shooters and perhaps provides a template of how a spring gun breaks in.

How chronographs changed airgunning–and not always for the best!

by Tom Gaylord, a.k.a. B.B. Pelletier

This topic was suggested by veteran blog reader Kevin. I liked it because it gives me a chance to say some things to the new airgunners; better yet, it’s a great way to start a discussion among all you readers.

I will touch on the things about chronographs, which are near and dear to me, but I think my role today is simply to get the ball rolling. We have enough readers with chronograph experience that I’m sure they’ll share a lot of their own viewpoints — some of which may never have occurred to me.

What is a chronograph?
The term chronograph means different things to different people. To an horologist, it might mean a particularly accurate instrument (watch or clock) to record the passage of time; but to a shooter, it means an instrument that’s used to measure the velocity of a projectile. It still records the passage of time, but also performs an additional calculation to convert the results into velocity. As incredible as it sounds, we’re able to measure the speed of a pellet or bullet moving hundreds, or even thousands of feet per second with an instrument we can buy for as little as a hundred dollars.

Shooting Chrony Alpha Master chronograph
A modern chronograph is inexpensive and very accurate!

History
While ballistic chronographs have existed for more than a century, most of that time they were large, cumbersome, very expensive and difficult to use. It wasn’t until the 1960s that the first portable electronic chronographs became available to the common shooter — and even then they were still very costly and hard to use. You had to shoot through paper screens that had tiny wires running though them, and a sensor would detect when the resistance of the screen changed as some of the wires were broken by the bullet. These screens didn’t last very long in a shooting situation and had to be replaced when they could no longer detect the passage of the bullet. Time was wasted when things didn’t go as planned, and buying chronograph screens was an ongoing expense.

The early electronics were also quite troublesome from today’s perspective. They didn’t directly read out the velocity of the bullet. Instead, they registered the time that elapsed between screen one and screen two, detecting the passage of the bullet. And even that wasn’t direct! They did it by illuminating lights in various columns on a panel that the user had to interpret. The user took that number to a table and looked up the velocity. It wasn’t always given as one absolute speed, either. It was often given as a small range of velocities within which the bullet was traveling — like 2,140 to 2,148 feet per second. It was slow, crude and primitive, but it was the best we had at the time. This was also the time when we were using slide rules to solve complex math problems, and we accepted small margins of error when taking a reading.

These early electronic chronographs were also very imprecise by today’s standards. The precision of their internal “clock” was only about 1/10 to 1/40 that of today’s chronographs, so the number they gave…which was a best guess to begin with…was nowhere near as close as what we get from a modern instrument. Still, they gave us numbers, and we were fascinated by them.

When the first direct-reading chronograph (one that displayed the actual velocity of the projectile) came out, it boosted sales worldwide. Then, chronographs were easy enough for the average user. And when the first photo-sensitive sensors (skyscreens) came out, they did away with the expense and frustration of the old paper-and-wire screens. Both these things happened some time in the 1970s, if I remember correctly. That was when the private use of chronographs really took off.

A skyscreen senses the passage of a projectile by detecting the slight drop in light when the shadow of a pellet or bullet in flight passes over the sensor. Since the light source is often the sky, the name skyscreen became common. This is both good and bad. Good because of how easy they are to use, but bad since accuracy depends on how well the screens are lighted — but that’s a different topic. Today, I want to talk about what the availability of chronographs does…both for and to airgunners.

You use a chronograph to establish the velocity at which a pellet is traveling. All well and good. But the first time you actually do it, you’ll probably be awed by what’s happening. Then, one of two things can happen. You can either put aside your awe and get to work or become enraptured by the numbers the machine gives you and lose sight of everything else. I think that’s what Kevin wanted me to talk about when he suggested today’s topic

Problem No. 1: Speed rapture
The user becomes so engrossed in watching the chronograph readout that everything else stops. This once-sane fellow who used to love nothing more than making acorns dance with his pellet rifle now sits slack-jawed in front of his chronograph, watching the screen for the next number to appear. He no longer shoots at targets. He no longer cleans his gun. He just watches that screen. In extreme cases, he invents things to launch, just to see how fast they go. The chronograph has turned a shooter into a nerd. It’s the equivalent of an addition to a social network; and whether you like them or hate them, you’ve all seen what can happen when the network, itself, becomes the sole focus of a person’s attention.

Problem No. 2: Infinite dissatisfaction
The chronograph owner uses his machine to determine how much he likes a certain airgun. Because nothing is ever perfect, he’s never satisfied with anything. His chronograph has become like the magic mirror on the wall — but one with an extreme personality disorder. It spray-paints dissatisfaction on the overpass of his life.

This guy will buy an airgun, then shoot it over the chronograph until it fails to please him. You see, he’s learned that if you do something long enough, eventually you get the results that come from the bad side of the curve. When that happens, it sets off his spring-loaded trigger of dissatisfaction, as in, “I knew this rifle wasn’t as good as they said! And here’s the proof!” As Midas was unable to survive when everything he touched turned to gold, this fellow is in pretty much in the same boat; though, when he touches things, they turn into something far more objectionable.

Problem No. 3: The statistian
This shooter used to be the life of the party until he got his chronograph. He now carries a notebook full of columns of numbers that he will try to work into any conversation. You’ll ask him how things are going, and he’ll whip out a spiral-bound notebook with the numbers he’s collected over the past six months. Somewhere in all that data is the answer to how he’s doing — he just can’t quite put it into words. But he’s got the number to back it up! How’s he doing? Please turn to page 46.

Problem No. 4: Dazzled by the charts
This guy takes his chronograph numbers and creates charts with them. But he’s never taken a statistics course, so he isn’t really sure what the numbers are telling him. But he has found that he can tweak the presentation of the numbers on the charts to make them look any way he wants. For him, happiness lies in finding the best way to make his new airgun look good by adjusting the values on the scales of the charts. He’s really the same as guy No. 2, only his outlook is positive, where No. 2′s outlook is — well — it’s No. 2.

What good are chronographs?
It probably sounds like I’m against the use of chronographs, but that really isn’t the case. However, I do advise using them as tools — not as crutches. For example, do you first find the fastest pellet, then see how accurate it is? Of course not! First, you find the most accurate pellet, then see how fast it goes. If it doesn’t hit what you aim at, its velocity is secondary.

I see the same thing with those who reload centerfire firearm ammunition. They keep searching for the fastest load for a particular gun, with one eye always on the chronograph screen. They seem oblivious to what that cartridge is doing downrange — just as long as it’s the fastest in their gun. They paid for the speed their rifle can deliver, and by gosh, they’re going to get it! It’s akin to being the “fairest in the land,” don’t you think?

I turn this around by never consulting the chronograph until I have the most accurate round. Whether it’s a centerfire cartridge or a pellet, it’s all the same to me. I want to hit my intended target. Once that happens, I get interested in velocity, but only to know how fast the projectile is going — not to tweak it to go faster.

Okay, Edith pointed out that I test velocity before accuracy in my blog tests. That isn’t in contradiction of what I just said, because when I test an airgun here I am seeing what it can do in general terms. In other words, I am looking at power independently of accuracy. But when I test a gun for myself (and spend a LOT longer doing it), I’m interesting in the optimum performance it can give — not in the average performance out of the box.

Chronographs as diagnostic tools
A great use for a chronograph is to test the health of your airgun. If you know how fast it shoots with certain pellets, you can always test it again to see whether anything has changed. I’ve found things like broken mainsprings this way.

You can also use a chronograph to estimate performance of a certain pellet or gun. If, for example, there is an 80 foot-per-second variation in the velocity of a certain pellet in a certain gun, you can be pretty sure that gun will not shoot tight groups with that pellet at long range. They will be elongated on the vertical axis due to the large velocity difference.

Chronographs can also be used to calculate more complex things, such as the ballistic coefficient of a projectile by measuring its velocity at various distances from the muzzle. For this, you need more than one instrument since each projectile must have multiple readings along its flight path.

When I worked at AirForce Airguns, I used a chronograph to test the results of various repair jobs we did to customer guns. Of course, we never knew what the gun was doing before it encountered whatever problem it might have had, but we did know the parameters of a healthy gun. When the rifle was performing within those parameters, it was deemed to be fixed. You may have noticed that I often refer to the Crosman Premier pellet as a “standard candle.” That’s my slang way of saying that I use it in a diagnostic role since I know how fast a healthy AirForce rifle is supposed to shoot it.

There are also numerous other uses for chronographs, such as determining the energy a certain pellet generates, finding the optimum performance curve with a PCP gun and counting the number of useful shots you can get from a CO2 cartridge.

Before there were chronographs, shooters focused on hitting the target. They didn’t talk about velocity — they talked about power, as in, “This pellet rifle is powerful enough to shoot through a one-inch board.” After chronographs became widely available, some people lost sight of why they were shooting and became mesmerized by those alluring numbers.

You know that pellet guns are sold today on the basis of how fast they shoot. There are allusions to accuracy in the advertisements, but the velocity is always given. That’s what the modern chronograph has done to and for airgunning.

Chronographs are wonderful instruments, as long as they stay in their rightful place. Just don’t allow them to take over your shooting life and push the more important things aside.

What do advertised airgun velocity numbers mean?

by Tom Gaylord, a.k.a. B.B. Pelletier

Yesterday, I told blog reader Victor that this report was for him, but I think it’s for a lot of folks who are relatively new to this blog. Here’s the premise of the report: Airguns are usually advertised with their expected top velocities. What do those numbers represent? Today, I’ll attempt to explain this as clearly as I can.

The numbers are just lies!
Let’s get this one out of the way first because it seems to be the prevailing belief that advertised velocities are nothing but lies put forth by marketing departments to sell more guns. There’s some truth to this belief, but it isn’t 100 percent by any means. Here’s what’s going on with the lies.

In the 1970s, spring-piston air rifles broke the 800 f.p.s. “barrier” for the first time. Three guns — the BSF S55/60/70, the Diana 45 and the FWB 124 all topped 800 f.p.s. in .177 caliber…and the HW 35 came very close to 800. That started the velocity wars that are still with us today. In 1981/82, the Beeman R1, which was also produced as the HW 80, hit 940 f.p.s. in .177. A year later, it was hitting 1,000 f.p.s. right out of the box, and that became the new standard for magnum airguns.

A couple years after that, Diana offered 1,100 f.p.s. with their sidelever models 48 and 52, and from that point on it was necessary to go even faster to gain recognition in the air rifle class. A thousand feet per second was now considered the lowest velocity a magnum airgun should achieve in .177 caliber.

Then, Gamo upped the ante with their 1200 Hunter Magnum that became the 1250 a year after it was introduced. This was in the late 1990s, and I was writing The Airgun Letter, so I obtained a 1250 from Gamo and tested it for myself. To my utter surprise, that test rifle achieved 1,257 f.p.s. with an RWS Hobby pellet. I thought the game was finally over. Boy, was I mistaken.

Within five years, air rifles started hitting the market with claims of over 1,300 f.p.s. And then they bumped up to 1,350 f.p.s. You could almost hear the various marketing departments discussing what they had to say in order to sell their next new magnum air rifle. But when I tested these guns, they fell short of their advertised marks. I was not quiet about that fact; but when the box on the store shelf says one thing and I say another, guess which one people believe?

The numbers kept right on climbing — up past 1,400 f.p.s., then 1,500 f.p.s. and finally stopping at 1,650 f.p.s. I’ve also tested many of these newer rifles; and while they often do achieve velocities that used to be impossible, like over 1,300 f.p.s., none has ever hit 1,500 f.p.s. without some kind of fuel-air explosion being involved. The fastest velocity I’ve ever recorded from a spring-piston air rifle was just at or under 1,400 f.p.s., and one person reported he had achieved a legitimate velocity of 1,425 f.p.s. I’m talking only about spring-piston air rifles now, because a .177 AirForce Condor has hit 1,486 f.p.s. in one of my tests.

Non-lead pellets
While all these velocity claims were stacking up, the market was also flooded with lead-free pellets. Being lighter than lead pellets, these pellets went faster at the muzzle. The fact that they could not carry that velocity very far downrange was lost on the majority of people. One ambulance-chaser “expert” witness in a wrongful airgun death lawsuit went so far as to compare a magnum air rifle pellet to a .22 rimfire bullet fired from a handgun. He “demonstrated” on television that the airgun was faster than the firearm with no mention of the effects of a lightweight pellet compared to a 40-grain bullet. Well, a neutrino travels at nearly the speed of light and passes through the earth unresisted; but since it has almost no mass, it doesn’t do any damage. Velocity alone means little.

That is the story of the velocity claims for pellet guns that are either outright lies (where the actual number you can achieve without resorting to some trickery is lower than the claimed velocity) or are stretching the truth beyond credibility (where ultra-lightweight pellets are used to obtain the number).

Legal concerns
This issue is the one I believe many folks do not consider when they focus on velocity claims that seem unrealistic. While we would never consider shooting a lead-free 5-grain pellet in a magnum air rifle, or in almost any air rifle, for that matter, there’s a reason to do it. Some communities and states have laws specifying the maximum velocity an airgun can legally achieve. If it exceeds that — well, the outcome isn’t clear because these laws are written in many different ways.

In one jurisdiction, the law may set an absolute maximum velocity for the airgun. No projectile weight is usually given in such a law, so if any pellet can exceed the maximum, the gun is not legal there. Working against such laws are the companies that make plastic airgun pellets weighing 3 grains or less. They will scream out of the muzzle and through the chronograph before slowing down as though they are tethered to the gun! Such pellets may bring a smile in certain places, but they can bring down the law in other places that have maximum velocity laws. The only thing that has kept many airguns safe so far is the general lack of knowledge that such pellets exist.

In another community, the law may include both a velocity maximum and a maximum muzzle energy. This law can be written two different ways. One is if the airgun surpasses either maximum it violates the law. The other way the law can be written is that the airgun must surpass both criteria before it violates the law.

Airgun manufacturers do not know all the laws that are in force. There’s no way they can because new laws are written all the time, and existing laws are modified or clarified to change their impact. In a country like the United Kingdom, where the law is relatively straightforward — keep the muzzle energy under 12 foot-pounds to stay legal as an airgun, the manufacturers have a parameter they can build to. But in a country like the United States — where airguns are totally unregulated in some places and highly regulated in others, a manufacturer stands little chance of remaining abreast of the law.

They do their best to comply with the laws they know and hope that companies like Pyramyd Air, who sell their products, will stay on top of things, too. They (the manufacturers) watch the big trends and try to tailor their products to those, and they trust their dealers to know the market they sell to.

Edith serves in this capacity for Pyramyd Air. She monitors state and local laws, and she calls the attorney general of any jurisdiction or state authorities if she finds the laws have changed or are going to change. Sometimes, she gets solid answers that can be trusted, but other times she discovers that the people in charge are not aware of how to interpret their own laws.

One example of this was in a Midwestern state that we won’t name to spare them embarrassment. Edith was unable to get an answer to a question about a law. She spoke to person after person in that state’s division that regulates guns. One time, she ended up speaking to a woman who was the head of the entire division because she’d gotten 5 different interpretations from 5 different officers. During the conversation, the head of the division mentioned that the ATF regulates all .50-caliber guns so the state didn’t have to regulate .50-caliber airguns. Of course, Edith explained that .50-caliber airguns are sold coast to coast in the U.S. and, except for a few states, are totally unregulated. Nothing she said could convince this woman. After all, Edith was just some person calling this police authority, so how could she know better. Sometimes, it’s impossible to counter ignorance.

Company velocity criteria
Some airgun manufacturers categorize their guns by the velocity they produce. Daisy is one that does. They have youth products separate from their Powerline products. They recommend their Powerline products for shooters 16 years and older. I searched the Daisy website looking for the velocity break between a youth gun and a Powerline gun but didn’t find a number. But looking at what the Powerline models deliver, it looks like it’s any gun capable of shooting faster than 600 f.p.s. in a long gun and all handguns. There’s also the Avanti line, which is for target shooting; and, while all the long guns shoot under 600 f.p.s. and are considered youth models, there are 2 pistols in the Avanti line and the Powerline designation is in their model names.

What does this mean to an airgunner?
An airgunner has no way of knowing the meaning of the velocity number that’s given with a particular airgun. It could be for bragging rights, or it could be the fastest velocity the company engineers were able to obtain from the gun under controlled conditions. They could be using the number to sell more guns to uneducated shooters, or they could be using it to segregate their products for sales to different jurisdictions.

Company A tests all their guns with real-world lead pellets that shooters might also use. AirForce Airguns is one such company, and they even tell you what the test pellet is (a Crosman Premier pellet of the appropriate caliber, by the way). Company B is run by the marketing department, and they inflate the velocities of their magnum line of rifles and pistols by 10 percent. I’ve had executives in these companies tell me they did this because — to use their own words — “Everyone else does it, so why shouldn’t we?”

Company C uses the lightest pellets they can find to test their guns, so they don’t run afoul of those places where velocity, alone, is the criteria. And so it goes. This is why it’s impossible to know what the velocity figures mean unless you know the company that publishes them and their policies.

And the answer is…
The answer is — there is no one answer. Airgun velocity is a complex topic that’s driven by forces both within and outside the company making the guns. This is where the budding airgunner has to become a thoughtful researcher when looking for a certain gun. Pyramyd Air tries to post the most correct velocity for each model, but they’re at the mercy of both the airgun manufacturers as well as the makers of pellets.

Experience is the best guide when it comes to this topic. With experience, you’ll know what the limits are, which companies do what with their numbers and so on. But never think for a moment that all published velocities are incorrect.

Favorites

by Tom Gaylord, a.k.a. B.B. Pelletier

The reaction to the accuracy test with the Cometa Fusion Premier Star air rifle brought a lot of feelings to the surface. Those feelings impressed me to the point of writing this report.

I don’t like all airguns equally. And there are some airguns that I really don’t care for at all. But I can’t overlook any of them because someone does care. Someone does like exactly the gun I don’t like, and to them that gun is a delight in many ways. So, regardless of how I feel, I try to put my feelings aside when I look at an airgun for the first time.

Let me get specific without naming any names. Some of you dislike spring guns. You find them difficult to shoot and not as accurate as you would like.

Then there are others who like only spring guns. The rest of the airguns can go to the landfill, as far as they’re concerned.

I could go on and do the same for each powerplant, but I think you get what I’m saying. Each type of airgun has its fans and also its detractors. Nothing new there!

But what if there’s a wonderful experience awaiting you, and it’s buried deep inside a pile of airguns you’re not interested in? What happens then?

Many years ago when The Airgun Letter was still being published, a local reader called me to “pick my brain.” That was what they always said — they wanted to pick my brain. But after a couple hundred times of getting my brain picked, I discovered that wasn’t what they wanted at all. They could care less about what I thought. What they really wanted was for me to agree with them that what they thought was right.

So, this one reader told me that he’d just bought an RWS Diana 34. He thought it was very expensive for what it was, but maybe I could help him understand why it cost so much and was so inaccurate. Well, it turned out that this guy had read all about the artillery hold in my newsletter, but he never tried it. Naturally, he wasn’t getting any accuracy from his new rifle. Once I convinced him that the artillery hold really worked and he should try it, he did. Then, he was delighted with his new airgun! For awhile, anyway.

A couple more weeks passed and I got another call from the guy. Had I ever heard of the Beeman Crow Magnum air rifle? Yes, I had. Then why, he wondered, had I not told him about it when he called to tell me about his Diana 34? What do you say to that?

I think I then told him that the Daystate Huntsman pellet rifle was extremely accurate, to which he responded that he could never be interested in a precharged airgun because of all the other stuff you had to buy to go with it.

This man was not ready to hear about precharged air rifles, so nothing I said was going to have any impact. At this point in time he was in the midst of his spring-gun days and that was all he was interested in, thank you very much. If he then took up precharged guns a year later, he would probably wonder where they had been all his life; but until he made the decision to change, they were invisible to him.

We have the same thing going on here on this blog. Some of you are interested only in 10-meter target guns and find the rest of the stuff we cover to be a bore. You tolerate the other stuff out of politeness, waiting for your turn in the sun. As far as you’re concerned, I don’t address the most important topics often enough because I’m always wasting my time on things nobody cares about.

I get that. I understand it, and I don’t want to change you one bit. However — please acknowledge that there are airgun-related things that you might find very enjoying, but they’re buried deep in the bowels of the stuff that doesn’t interest you right now. My job is to show you everything, so you can see if any of it is of interest.

Okay, here is something else that’s hard to deal with. Two men talk about accuracy and one says something like, “I don’t like it when an airgun is too easy to shoot accurately. I like it to be a challenge!”

WHAT?

Then I see a group that pleases this shooter — 5 shots at 20 yards that can be covered by a quarter. He thinks that’s accurate. And I’m not going to argue with him. If he thinks it’s accurate, then it is.

But the other fellow wants to put 10 shots inside a quarter-inch at 40 yards. That’s his definition of accuracy. He would not think much of a 20-yard, 5-shot group that fits under a quarter. In fact, he would think it was a failure.

I have to talk about accuracy to both these guys, as well as to the guy with the abacus in his hand who always couches everything he says with the term “for the price.”

If I could transport some of you to my range and put a Fast Deer or an Evanix Conquest in your hands and let you experience what I have, I bet I’d see the smiles on your faces. Even you diehard spring-gun chaps would have to admit that putting 10 pellets into a half-inch at 50 yards with a Condor is fun stuff. And those who think the Benjamin 392 is all they’ll ever need still find a Diana 27 captivating the first time they shoot one. Shooting one after shooting a multi-pumper feels like walking across a carpet in your stocking feet after trudging 10 miles through deep snow.

I guess what I am saying is that most of us need a bucket list of things we’re going to do before we leave the range for the last time. Even if chocolate-covered baby bees do not become your personal favorite snack food, it’s good to say you’ve tried them one time. Not all chicken tastes like rattlesnake, you know.

Last word
I’ll leave you with this. I didn’t say it — blog reader Victor did.

I was just explaining to a friend this Sunday that you have to take customer reviews with a grain of salt when it comes to new springers. I told him that a lot of customers write bad reviews because they simply don’t know some basic things about technique, but that once they know…everything changes. Suddenly, that inaccurate rifle that they hated becomes accurate. He said that had it not been for me teaching him how to shoot a springer, that he would have been one of those negative reviews.

Relating to this article, the first time I let him try a few of my air rifles, one of them had a freshly installed scope, and we experience the “floating erector tube” issue. Like this Cometa rifle, my groups just wandered about. It wasn’t until the next session that it started to work. Now, that scope and rifle are performing very well.

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