Pneumatic Pnews

Monday, July 31, 2006

Tech Force 99: Part 2

by Tex Force

Continuing our look at the Tech Force 99, I chronographed my rifle with four pellets: Beeman Kodiak, JSB Exact 10.2-grain, H&N Finale Match and RWS Hobby. The Kodiaks averagerd 633 f.p.s. with a standard deviation of just 4 f.p.s. That's tight and good for long-range accuracy. The JSB averaged 684 f.p.s. with an SD of 5 f.p.s. The H&N Match pellets weigh only 7.6 grains and averaged 793 f.p.s with an SD of 19 f.p.s., which is pretty large. The Hobby pellets averaged 883 f.p.s., but they had a velocity spread from 807 to 978, so they are out the window for accuracy testing.

The cocking effort of my rifle is about 30 lbs. I measure it with a spring hay scale attached to the underlever. While it isn't exact, it does give a good ballpark number.

Sights
While the TF99 has adjustable open sights, I mounted a Tech Force 3-12x scope for better accuracy. The rifle has a scope stop already built in, so you don't need a mount with a stop of its own.


The TF99 comes with a built-in scope stop. Just butt the rear scope mount against this stop, and everything will be rigid.



Tech Force 3-12x scope is perfect for the TF 99. It mounts with plenty of clearance for loading.


On the basis of velocity, both the Kodiak and JSB pellets looked best. The H&N Match also looked like it might work, but things didn't work out that way at the range. I shot at 18 yards, and all shooting was off a bench, with the rifle rested on a sandbag AND floated on my hand (which rested on a bag). The TF 99 definitely likes to be floated with as light a touch as you can manage. Hold it tight ,and the groups open up to over 2" - even at 18 yards. Hold it very lightly so it can move and recoil, however, and the groups shrink right up.

The JSB pellets turned out to be the worst pellets, grouping up to 1.5" with a light hold (the best hold for all pellets with this rifle). I can't recommend using them in this gun. The H&N Finale Match turned in some 1" groups, which is okay but not great. But Beeman Kodiak pellets saved the day with groups hovering around 0.5" to 0.75" when the rifle was lightly held. Off the sandbag, they opened to greater than 2".

Good trigger
The TF 99 has a light trigger-pull. It's long and a bit creepy, but so light that I don't think most shooters will mind. When the rifle is cocked, the moving compression chamber locks to the back so you can load a pellet into the breech. There is plenty of room, but it will take several tries before you become good at it. You have to reach into an opening in the side of the outer tube, and there isn't a lot of room for your fingers. However, like I said, you will get used to it.

Safety, safety, safety!
There is a beartrap lock that holds the sliding chamber back but don't depend on it. Hold the end of the underlever tight enough to catch the spring should the beartrap latch fail. That will keep your fingers safe at all times. When you've loaded the rifle, depress the beartrap latch at the rear of the triggrguard to rotate the underlever back to its stored position. All good underlever guns with sliding chambers have latches like this. Or they should! Also, the safety must be taken off before you fire the gun.


The TF99 trigger is light and easy to get used to. The lever behind it releases the beartrap device so the underlever can be stored. The lever in front is the safety.


Shooting
Recoil is light, and the action is quite smooth when the gun fires. It acts like a nice European spring rifle rather than a typical Chinese airgun. Once you get used to the trigger, your groups will start shrinking if you remember to let the rifle move as much as it wants to when it fires.

The TF99 is a large spring rifle with light cocking and a smooth firing behavior. Accuracy depends on a soft hold and the right pellet, which I found was the Beeman Kodiak.

Monday, July 24, 2006

Tech Force 99: Part 1

by Tex Force

A reader who calls himself sav300 asked for a look at the Tech Force 99, so today I'll begin.

Where it came from
As you may know, Compasseco redefined the Chinese air rifle; not just in America, but for the entire world. They did it by starting a product improvement program on certain Chinese airguns and accessories to bring them up to European and American specifications. They knew the Chinese were capable of building better products, but nobody was showing them what was needed or desired in the airgun arena. So, they stepped in.

The target was the TX200
Compasseco knew that the TX200 from Air Arms was the most highly regarded spring air rifle of the day (the late 1990s, and still true today). That became the target. Could a Chinese air rifle be made as well as a TX200? It would have to equal it in fit, finish, power and accuracy. Compasseco was dealing with the Shanghai Air Gun Factory, an employee-owned and operated firm. They still had operate within the laws and regulations of the People's Republic of China, but those laws and regulations had relaxed in the area of consumer products, so almost anything was possible.

The challenge
To a person who doesn't understand how a factory operates, it might seem that all you have to do is make each piece exactly like a TX200, then assemble them and you're done. That's the same as saying that it doesn't take a sculptor to chisel an elephant out of a block of marble - just remove everything that doesn't look like an elephant!

When a factory undertakes a new design, they have to figure out how to achieve it with their existing equipment. If the Air Arms plant in England uses a $500,000 CNC mill to produce a certain part and the Chinese plant has a 30 year-old turret lathe that is only one-tenth as accurate, they have to figure out how to use their machine to do the work of the CNC mill. Even the Chinese cannot afford to spend an hour to make a part that is made in England in four minutes! When the difference cannot be made up by spending more time and care, other manufacturing processes (finishing, for example) are brought to bear to make up the difference. If the British plant can obtain seamless hydraulic tubing with a micro-finished interior that they can pass a reamer through once and end up with a compression chamber, but the Chinese plant can't, they have to find a way to work around the problem.

So, you don't just build a TX200 on the first try! Compasseco and the Chinese engineers formed a team that examined the rifles currently being built and selected the QB 36 underlever as a good starting point. The 36 was a Chinese attempt at producing a higher quality air rifle, so it was already headed in the right direction. And, it was an underlever.

Improvement by increments
The design team selected several features that needed improvement and set to work on them. Among these were the uniformity of the compression chamber, the quality of the mainspring, the quality of the front and rear sights, the quality of the underlever latch and the quality of the stock. Each of these features took many hours of engineering design work, prototype fabrication, and testing and sending samples back and forth from China to the United States. Several times a year, Compasseco representatives visited the plant in China for design reviews.

The short version
To cut to the chase, the first major milestone in this project was the introduction of the Tech Force 97 rifle. It was unveiled at the 1999 SHOT Show in Atlanta in February. Yvette Hicks, a Compasseco rep, could cock the rifle with one finger! A report written by Jess Galan gave 1/8" groups at 10 meters. It was quite a rifle!

Continued next week...

Monday, July 17, 2006

Daisy 499: the world's most accurate BB gun!

by Tex Force

In 1965, Daisy teamed up with the U.S. Jaycees to teach children to shoot. The program was centered around BB guns, but in the beginning there was no standard gun to use. Daisy promoted its model 99 Target Special that had been around since 1959, but it was a stop-gap measure. The gun did have good aperture sights, but the sling wasn't useful for target shooting and accuracy was mediocre.

In 1975, Daisy came out with the model 299, a 99-based gun with 1,000-shot gravity feed. It lasted only two years. Coaches who used the 299 and 99 have told me they would swap shot tubes to find one that shot better than the rest. Apparently, there's enough variation in bore diameter to make that kind of difference.

Enter the 499
In 1976, Daisy brought out a radical new model named the 499. It was a muzzle-loaded single-shot that had a precision smoothbore barrel to better handle BB shot. Although most places list BB shot as 0.175", it is actually smaller. That was one of the problems with the earlier BB guns, and it's also the reason you can't do well on targets with a Red Ryder. The overly large bores of most BB guns allow the 0.173" BBs to bounce around on their way down the barrel. The 499 has a bore just large enough to allow the BB to pass without excessive friction, and holding that tolerance is one reason the gun costs as much as it does.

Never meant for the public
Like a set of soapbox derby wheels, the Daisy 499 was not created for public consumption. It was designed specifically to support shooters competing in the International BB Gun Championship Match. Unlike other BB guns with dubious accuracy, the 499 will out-perform any shooter alive! It is exactly like an Olympic 10-meter rifle or pistol that can shoot better than humanly possible. The official range for BB gun competition is five meters, which is 16.4 feet. At that distance, the 499 will put every BB through the same hole if it is held right.

Special shot available
Like the barrel, the size of BB shot also needs to be closely controlled. Up to 10 years ago, regular BBs were not precise enough to deliver the full accuracy the 499 can achieve. Daisy produces special Precision Ground Shot just for this gun. For many years, they made only enough shot for competitors (they have in excess of a quarter million shooters annually!), but Daisy now sells the shot to anyone. Call Customer Service at (800) 643-3458.

Regular BBs work well, too
Today's BBs are made so well that they get great accuracy from the Avanti 499 Champion. Few shooters can hold the gun steady enough to notice a difference between common BBs and Precision Ground Shot.

Targets
If you're getting a 499, don't forget to buy the correct 5 meter targets, too. The bull is smaller than a dime, yet you will find it hard to miss the 10-ring with this special BB gun.

Should your child compete?
If you have a child between the ages of 10-14, maybe they would be interested in the competition. Contact Daisy to find out how you can enter your child in a sponsored youth program that leads to the International BB Gun Championships.

We often regret the things from the "good old days" that have passed from the scene. Well, the Daisy 499 is a rare exception to that. It's the world's most accurate BB gun, and it's available today. If you really want a shooting surprise, get one for yourself!

Monday, July 10, 2006

RWS 5G Magnum

by Tex Force

The RWS 5G Magnum is one of the most powerful spring piston pistols made. It is ahead of the Beeman Hurricane and about equal to Beeman's powerful P1. RWS touted it as a 700 f.p.s. pistol, but it really shoots in the mid-500s with standard lead pellets. It might get close to 700 with Gamo's new Raptor pellet, but expect around 500 to 550 with pellets you are most likely to shoot.


RWS 5G Magnum is a large pellet pistol. Tex says it's like a short rifle.


A breakbarrel pistol
This pistol is powered by a spring-driven piston that's cocked by breaking the barrel down. This is identical to breakbarrel rifles, and, in fact, that's what the mechanism is based on. It's really a small rifle action housed in a pistol grip. That's good, because it means the gun is very accurate, besides being powerful. Shooting from a rest, you can expect groups the size of a dime at 15 and sometimes even 20 yards.


The barrel breaks all the way down to cock the spring that powers the piston. The screw in front of the trigger is for adjustment of trigger-pull.


Quick target acquisition
The front and rear sights have fiber-optic inserts for quick acquisition of the sight picture in field conditions. This gun is not really set up to accept a scope, so plan to use the sights it comes with. They're sporting sights, not target sights. Put the red dot of the front sight on the spot you want to hit instead of using a target-type 6 o'clock hold.

Adjustable trigger
The two-stage trigger is both crisp and adjustable. The first-stage length and the pull-weight can be adjusted, then locked down so they don't change. The normal breaking weight is about 3.3 lbs.

Power and accuracy for a lot less money!
The 5G Magnum is just over half the price of Beeman's P1 pistol but just as accurate and powerful. It's even less expensive than the Beeman Tempest or the Beeman Hurricane, but it's more accurate and more powerful than either of those fine pistols. So this is one heck of a buy!

What pellets?
For an airgun this accurate, you'll want to use the best pellets. Beeman's H&N Match pellets are a great pellet for the 5G, as are Compasseco's own Tech Force Match pellets.

A year-round airgun
Because it's spring-powered, the 5G will work in all kinds of weather and at any temperature. This is not a gun you have to put away for the winter. That spring also saves you the cost of CO2 cartridges. Simply cocking the pistol gives you more power than any pneumatic or gas pistol can offer. If you're looking for an air pistol to keep and use for years to come, the 5G Magnum might be just the ticket.

Monday, July 03, 2006

Tighten those groups! Pellet sorting brings extra accuracy

by Tex Force

When I want to shoot REALLY tight groups, I sort my pellets into groups by their weight and shoot only from one group.

Why sorting works
Any group of ballistic projectiles will perform more uniformly if they are exactly alike. The closer the projectiles are to each other, the less randomly they will act (there will still be variations).

There are probably an endless number of things you can evaluate on a pellet, but the weight is the one that gives you the greatest return on your effort. We can discuss the reasons why all day long - there might be a void in some of the pellets that destabilizes them in flight, a heavier pellet may be larger and therefore fit the bore tighter, etc. The discussions can go on forever, but it doesn't matter. Simply sorting pellets by their weight will improve their consistency, which means tighter groups. So how do you do it?

You need a scale
The best type of scale for this is a powder scale that reloaders use. It weighs very small amounts and measures in one-tenth grain increments. I just checked on ebay, and you can buy a scale for under $20, shipped.

Two kinds of scales
There are two kinds of powder scales - balance beam and electronic. They are equally accurate and measure in the same increments, but the electronic scale dampens much faster and is easier to use. With a balance beam scale, you keep adjusting the scale until the beam balances perfectly. The weight indicated is the weight you record. With an electronic scale, all you do is place the item on the scale and wait a few seconds for the readout to stop changing. The number that remains is the weight of the item. An electronic sale is about four times as fast as a balance beam.


A balance beam scale is accurate and inexpensive, but it takes longer to use.



An electronic scale is just as accurate as a balance beam, plus it works about four times faster. The price has dropped in the past few years. This scale sells new at Midway for less than $30!


Sort into groups
Once you have a scale, you can begin sorting pellets. A premium pellet will vary in weight by an amount that will sometimes surprise you. Let's look at Crosman Premier 10.5-grain .177 pellets for example. The weight is listed at 10.5 grains. When you sort, you will find that about 30 percent weigh 10.5 grains, another 35 percent weigh 10.4 grains. Twenty percent weigh 10.6 grains and that leaves 15 percent of the pellets that will weigh anywhere from 10.1 grains to 10.7 grains. Now, let's talk about what you do with these sorted pellets.

What to do with the different weight pellets
The three primary groups of pellets weigh 10.4, 10.5 and 10.6-grains. If I wanted to shoot the absolute best group possible AT LONG RANGE, I would use pellets from one group, only. If I were competing in a field target match, I'd use pellets from a single group. But here is the deal - IT DOESN'T MATTER WHICH GROUP YOU USE! That's right - with all three pellets, your group will shoot to the same point of aim out to around 50 yards. There will be very small differences, which is why you only use a single pellet weight, but the sight picture, in general, does not change. If you are shooting groups beyond 50 yards, then stick with a particular pellet weight because it starts to make a difference at that distance.

What about the lighter & heavier pellets you sorted?
As far as precision shooting goes, they're junk! They can be used for function-firing or in cheap airguns, but don't use them when you want the best accuracy. The lighter pellets are the worst, as far as accuracy goes, because they are the undersized pellets. They will give a precision airgun lots of trouble.