Air Arms Pro-Sport: Part 7

by Tom Gaylord
Writing as B.B. Pelletier

Air Arms Pro-Sport.

Part 1
Part 2
Part 3
Part 4
Part 5
Part 6

This report covers:

  • Disassembly
  • Rotate forward spring guide
  • The washers
  • Factory top hat
  • Last note
  • Assembly
  • Relubed
  • Gun back together
  • Velocity with RWS Hobbys
  • Velocity with Baracuda 5.50mm heads
  • Cocking effort
  • The question
  • Summary

Today we look at the Air Arms Pro-Sport with the Vortek PG3 tune kit installed at its most powerful setting. This test was suggested by reader Yogi in the comments to Part 5.

“To finish up the review, how about exploring the other 2 notches in the PG3 kit? Maybe one notch is full OEM power, second notch is the desired 12 foot-pounds, and the third one(the one you have it set on) is good for 10.5 foot-pounds.

This way you have a full report on the Pro-Sport AND the PG3 kit.”

I though that was a great idea. Unless I test it, who knows what the other notches will do? And also there are the two heavy washers that add weight to the piston and more tension to the mainspring.

What I won’t do is test every possible combination of the kit. Besides the three notches there are two washers, so that’s a possible 9 different combinations to test — low notch no washers, low notch one washer, low notch 2 washers, mid notch no washers etc.

Instead, I will go to the opposite end of possibilities and set the mainspring on the high notch with two washers installed. That will bracket the power possibilities.


The Pro-Sport came apart in a few minutes with no mainspring compressor needed. Remember that with this Vortek kit the pretension on the mainspring is even less than on the factory gun and even that doesn’t need a compressor.

Pro-Sport Vortek kit
The thousand-word picture. The mainspring is in the lowest notch from the previous tune. The two washers from the Vortek kit are going in ahead of the forward spring guide (black thing the mainspring is wound around) that’s inside the piston. The factory top hat is shown below. One of the washers is stuck to the tip of a magnet to show that it’s ferrous.

Rotate forward spring guide

To get the end of the mainspring into the highest notch in the base of the forward spring guide, the spring guide has to be rotated. However, the inside diameter of the relaxed spring is smaller than the outside diameter of the spring guide — so the spring is on the guide extremely tight. It look me 20 minutes of fiddling with a screwdriver to move the guide high enough to make the slight rotation that was needed. You don’t want to grab the base of the guide with pliers because it is synthetic!

After that was accomplished the rest of the job took mere minutes. But before I go there, let’s look at what I’m about to do.

The last tune was with the spring set in the lowest notch of the spring guide. And no washers were used. So the piston was almost as light as it could be. By removing the synthetic spring guide it would have been a few grains lighter, but the spring would then have had room to vibrate on the piston stem. Vibration is a bad thing, so those few grains of weight are well spent.

The washers

I weighed the two washers, which are steel. One weighed 85.5 grains and the other weighs 86.2 grains. When I add that the two should weigh 171.7, but for some reason my scale says 171.4 grains. We are talking about a weight difference of a postage stamp, so it may be more in the technique I was using to place them on the scale than any real weight difference. At any rate, an additional 171.4-grains of weight is being added to the Pro-Sport piston.

Pro-Sport Vortek washers
Both Vortek washers together weigh 171.4 grains. They will be going into the piston ahead of the mainspring.

Factory top hat

For curiosity I also weighed the factory top hat that goes into the piston like the washers. It weighs 352.2 grains, or 180.8 grains more than the two washers. It’s a little over twice the weight of the two washers. That’s interesting but I don’t know why.

Pro-Sport top hat
The factory steel top hat weighs 352.2 grains.

Last note

If someone reads this entire report they will discover that I removed the sliding compression chamber for the first tune in Part 5. I did it because the piston didn’t want to go into the chamber when I started assembling the gun. But it really isn’t necessary to do that. Just fiddle with the piston and the piston seal will eventually clear and go in the chamber. This time I did not remove the sliding chamber and the time to assemble was cut by several minutes.


I won’t show you the entire assembly of the rifle because that was covered pretty well in Part 5. I will just show you the order of the parts as they go back into the gun. The two washers go onto the piston rod first. They add that 171-grains of additional weight to the piston, which should change its performance with heavier pellets a little. They also add perhaps a quarter-inch or a little more of preload to the mainspring.

The higher notch on the spring guide also adds a little preload to the spring. I would guess that together the notches and the two washers add about 3/8-inch of preload. That isn’t much, so Yogi, I doubt we are going to see the factory spec with this kit. I think it may get a little closer to 12 foot-pounds, which is what the specs tell us to expect.

Pro-Sport notch
There is the end of the spring in the highest notch. It isn’t seated all the way but when I cock the rifle it will seat.

Pro-Sport assembly
And here is how the parts go back in the piston and then into the rifle.


Handling the parts during this procedure removed most of the Tune in a Tube that was on the outside of the mainspring, so I added just a bit as the spring went back into the gun. It was still coating the inside of the spring, the rear spring guide and the sliding chamber so I left those alone.

Gun back together

Excluding the 20 minutes I spent playing with the forward spring guide, the job took 30 minutes including pictures. That’s from shooting condition back to shooting condition. It was now time to test the results!

Velocity with RWS Hobbys

In the previous lightest possible tune the kit pushed 11.9-grain RWS Hobby pellets out at an average 633 f.p.s. for 10.59 foot-pounds at the muzzle. With the PG3 tune set to maximum the rifle now launches Hobbys at an average 667 f.p.s. for an energy of 11.76 foot-pounds. The lightest tune gave a velocity variation of 11 f.p.s. This tune gave a range of 16 f.p.s. — from 660 to 676 f.p.s.

Velocity with Baracuda 5.50mm heads

In the previous lightest possible tune the kit pushed H&N Baracuda pellets with 5.50mm heads out at an average 437 f.p.s. for 8.97 foot-pounds at the muzzle. But remember, we added 171.4-grains of weight to the piston besides increasing the mainspring preload. This time Baracudas average 463 f.p.s. for an average 10.07 foot-pounds at the end of the barrel. The spread previously was 10 f.p.s. and this time it’s 14 f.p.s. — 456 to 470 f.p.s.

Cocking effort

The cocking effort felt almost the same with possibly one or two more pounds of effort needed to cock the rifle. On my scale it measured 37 pounds of force required, where with the lightest tune it was 35 lbs. and from the factory 48 lbs.

Firing behavior

I can’t detect any difference in the firing behavior from the previous tune. Recoil seems the same, too.

The question

Should I test the rifle for accuracy again with this tune? It’s bound to be very close to where it was before.

And how should I send the rifle back to Pyramyd Air — with the tune just installed or returned to factory spec? I guess I’m asking whether you think anyone would want to purchase a .22-caliber Pro-Sport that has been tuned to 12 foot-pounds?


I don’t know if this is the last report or not. I’ll await your decision on that.

I have to say I am thoroughly impressed by the Vortek PG3 tune kit that delivered EXACTLY what was promised! With all the variables involved (TIAT and me being two of them) I think it’s remarkable it turned out as well as it did.

Umarex Synergis repeating underlever combo: Part 2

by Tom Gaylord
Writing as B.B. Pelletier

Umarex Synergis underlever repeating gas piston rifle.

Part 1

This report covers:

  • Does it stop cocking after the last pellet is shot?
  • Velocity JSB Exact 8.44-grain domes
  • Firing cycle
  • H&N Baracuda Match with a 4.50mm head
  • Air Arms Falcons
  • Trigger pull
  • Cocking effort
  • Summary

Okay, spring-gun repeater fans, today is the day we get started testing the new Umarex Synergis. Let’s go!

Does it stop cocking after the last pellet is shot?

No, it doesn’t. After the last shot is fired it is possible to cock the rifle and fire it again without a pellet in the breech — dry-firing it. Does dry-firing damage the gun? Not as much as it used to, but it’s still not recommended. You don’t have to treat your dry-fired rifle like a hand grenade with the pin pulled, but neither is it something you want to do intentionally. So, what do you do?

You watch the clear magazine lid for the two dots — red and white — to align. When the magazine is loaded they are off by one chamber/pellet. The clear part of the magazine is pointed back toward the shooter, so, except for the scope mounts getting in the way, this is easy to do.

Synergis mag full
The magazine is loaded into the rifle. If the underlever is forward there is a pellet in the breech and the gun is ready to fire. Remember, the safety is manual. As you keep shooting the white dot moves counter-clockwise around the magazine.

Synergis mag 2 shots
The third-to-last shot has been fired and two shots remain. The white dot that moves is coming around to the red dot.

Synergis mag empty
The dots are aligned. It’s time to reload the magazine. If you cock and shoot when the mag looks like this you will fire the gun dry.

Velocity JSB Exact 8.44-grain domes

Umarex sent a tin of JSB Exact 8.44-grain domed pellets with the test rifle, so I assume they are among the best in the Synergis. Therefore I started the test with them. I shot two pellets without chronographing them to wake up the action, and then ten for the first string. Ten pellets averaged 886 f.p.s. The spread ranged from a low of 879 to a high of 892 f.p.s.That’s a difference of 13 f.p.s. which is great for a brand new rifle.

At the average velocity this pellet generates 14.72 foot-pounds at the muzzle. That’s enough for some hunting and pesting, so let’s hope the rifle is accurate.

Firing cycle

The Synergis is smooth for a gas piston gun, but there is a definite jolt when it fires. There is no slap to the cheek, so the bad vibration has been dealt with.

H&N Baracuda Match with a 4.50mm head

Next to be tested was the H&N Baracuda Match with a 4.50mm head. These domes weigh 10.65 grains and are accurate in a lot of air rifles. The Synergis put them out at an average 818 f.p.s. which generates 15.83 foot-pounds at the muzzle. Usually heavier pellets decrease in muzzle energy in spring-piston airguns, so the Synergis seems to like this one. The spread went from 801 to 823 f.p.s. — a difference of 22 f.p.s.

Air Arms Falcons

The last pellet I tested was the Falcon from Air Arms. At 7.33-grains it is the lightest pellet I tested. It averaged 951 f.p.s. at the muzzle, generating 14.72 foot-pounds. But the spread was 31 f.p.s., going from 941 to 972 f.p.s. The 972 was the first shot and after than the velocity never topped 954 f.p.s., so I’m thinking the Falcon isn’t as unstable as the numbers show. The first shot may just have burned a little more chamber oil than the rest, because at this power level all spring guns diesel.

Okay — the Synergis is a 14.5-16 foot-pound rifle. That’s a good place to be for a .177. But what about that non-adjustable trigger?

Trigger pull

I told you in Part One that the trigger pull was something to experience. Now I’ll get down to the number. How does the number two strike you — as in a 2-pound pull? And, the safety is manual!!! Why, it’s as if Umarex is going to trust us to manage our own safety issues. Maybe I should stop trimming the hedges with my lawnmower?

Yes — just two pounds! I was mentally and physically prepared for my trigger finger to winch a 500-pound weight down a rocky road with a broken Come-Along (American slang for a cable or strap hoist), but this trigger broke like it wanted to! Brother-in-law, Bob, you’re gonna like this one!

Will all Synergis triggers be this nice? Did Umarex set this one up just for me? Who knows? What I do know is it’s really good and that means that other Synergis triggers can be made just as good if they don’t start out that way. I’m not saying they don’t — just that there are no worries. Guys — this trigger is one the chatter forums will start advising people to buy, once they get guns of their own to test. Kowabunga!

Cocking effort

Okay — here we go. I mow my own lawn. It’s a postage stamp, and I mow it. Why do you care? Well, if you hire a service to mow your postage-stamp lawn then you probably don’t like lifting or pulling much of anything. So, when I say the Synergis cocks easy for a gas piston gun, that’s like saying I can run a mile in 8.5 minutes. That’s not terribly fast but there are some folks who drive to the mailbox at the end of their driveway. They will not be on the same sheet of music as me.

The Synergis I am testing cocks with exactly 30 pounds of effort. For a gas piston or gas spring, that is light! I remember when the cocking effort for gas springs hovered around 45-50 pounds and went up from there.


That’s it for this report. I have to say this Synergis is looking better at every turn. I sure hope it’s accurate, and, yes, I’m mounting the scope that came with it.

Stoeger S4000E Black Synthetic Suppressed rifle combo: Part 5

by Tom Gaylord
Writing as B.B. Pelletier

Stoeger S4000E MGS
Stoeger S4000E breakbarrel rifle.

Part 1
Part 2
Part 3
Part 4

This report covers:

  • Good comments
  • Cleaning the barrel
  • Baffles and sights
  • Stock screws
  • Tight hold
  • Pellets, pellets…
  • The secret
  • Relax!
  • The next day
  • Other pellets
  • 10 shots
  • Discussion
  • Is this a world-beater?
  • Summary

Today I will finish testing the Stoeger S4000E rifle at 25 yards, and what a tale I have to tell you! Grab your coffee and let’s get started.

We already saw the rifle shot at 25 yards and the groups were not that impressive. But I saw a potential that I sometimes see that made me work harder with this rifle for many reasons. Today you will see why I do that and also what it sometimes takes to make an air rifle shoot.

Good comments

Several readers commented on my Part 4 report. Some commiserated with the outcome but a couple gave me good suggestions for things I ought to try next time. RidgeRunner reminded me to clean the barrel with JB Non-Embedding Bore Cleaning Compound. I should have done that before but I missed it, and thankfully RR was there to remind me.

Cleaning the barrel

Because the S4000E has a gas piston you can cock it and leave it cocked without worrying about the mainspring. Compressed air does not take a set! That makes cleaning the barrel much easier because there is no time crunch.

I cleaned the barrel with a brass brush filled with plenty of JB Compound, but I’ll tell you, the barrel wasn’t that dirty. Sure some stuff came out, but where a brass brush will usually take a lot of force for the first 10-12 passes each way, in this rifle the barrel was smooth in just two. I still ran the brush all the way through the bore both ways 20 times and followed that by cleaning and drying the bore thoroughly. Whatever the condition of the bore was before, it wouldn’t be a factor anymore.

Baffles and sights

RidgeRunner also thought I might try mounting a dot sight to see what that would do. I did that and it did nothing. And he thought the baffles could be a problem. I examined them when I cleaned the bore and they weren’t.

Stock screws

Reader Rk reminded me to check the stock screws. The two on the forearm were tight but the one behind the triggerguard was loose. When I tightened it, the entire barreled action was sucked down into the stock. That is real bad for accuracy! After that I checked that screw about every 20 shots.

Tight hold

Reader Silentsniper gave me his special tight hold for guns with gas springs. I tried it first and shot 5 H&N Baracuda Match pellets with 5.53mm heads into 2.047-inches at 25 yards. Maybe I didn’t hold it right, but I tried doing exactly what he said. That was too bad because he had me grasping the forearm at exactly the place the rifle’s designers wanted me to hold it. It felt great; it just didn’t work.

S4000E tight hold group
When I held the rifle with a tight grip as reader Silentsniper advised, five H&N Baracuda Match pellets went into 2.047-inches at 25 yards. In the picture the head of the pellet rolled into one of the pellet holes and I didn’t notice it until I ran the photo through Photoshop for this report. Sorry.

Pellets, pellets…

I tried about 12 different pellets — all without success. I also tried many variations of holds. I had the UTG Reflex Micro dot sight mounted for some of this and then I replaced it with the factory 4-power scope. Like in Part 4, I would get three pellets in a good group, then two fliers. That happened with either sight. It didn’t happen with every pellet I tried, but it happened often enough that I knew the rifle is accurate. I shot a total of 95 pellets on the second day of 25-yard testing before finding the secret.

The secret

At the end of a multi-hour session I suddenly remembered the most hold-sensitive spring-piston air rifle I ever tested. It was a Beeman Crow Magnum, which is another name for a Theoben Eliminator. When I wrote my newsletter I could not get that rifle to shoot! I changed barrels from .25 caliber to .20 caliber because many people advised me that was the way to go. I even had Ben Taylor — the Ben in Theoben — talk me through cleaning the barrel at the SHOT Show years ago! Nothing could make that pellet-shooting jackhammer work — until I found out what could. It is the most fundamental level of the artillery hold. I describe it in my videos but I seldom do it because it takes so much concentration.


Relax — that is the big secret! Get into your hold, put the crosshairs in the center of the bull, then close your eyes and relax. Relax completely! Open your eyes, and, if the crosshairs are still within a half-inch of where you want to shoot, line them back up and take the shot. If they aren’t, adjust your hold and body until they stay there. This procedure guarantees that when the rifle recoils it won’t go in some direction that your body is spring-loaded to send it. It will always recoil the exact same way every time.

If the crosshairs move when you relax, try shifting your elbows, your feet and even the position of your hand on the rest. Don’t stop until those crosshairs stay where you want them when you relax. I did this for shots 91 to 95 with JSB Exact RS pellets and look what happened! Five pellets landed in 0.957-inches at 25 yards. I know that isn’t as tight as we would like to see, but I had been shooting for several hours to get to this point!

S4000E best hold group 1
The last group of a long shooting session netted me this. Five shots are in 0.957-inches at 25 yards. There are 6 shots on this target, but the lower left hole is from a sight-in. It doesn’t belong to this group.

By this time in the day I was very tired. Rather than shoot another group, I adjusted the scope two clicks up and two clicks to the left and put the rifle away. The next morning I would be rested and ready to do my best.

The next day

And I did great! The first two shots went where they had gone before from scope stiction (the crosshairs don’t move when the adjustments are made, but after one or two shots they are jarred loose and suddenly shift to the new location). The first group I shot was 5 JSB Exact RS pellets in 0.547-inches at 25 yards. I relaxed for each shot and really concentrated on doing my best. It paid off. The S4000E rifle is accurate — just like I thought.

S4000E best hold group 2
At 25 yards the S4000E put 5 JSB Exact RS pellets in 0.547-inches when I did my part.

Other pellets

I then tried to shoot two different pellets and missed the target paper completely with four shots. I started to adjust the scope for the second pellet when it dawned on me — what was I doing? I already knew a pellet that was accurate. Let’s see how accurate it is.

10 shots

This time I wanted to shoot 10 shots, to show that the 5-shot groups from the day before and this morning were not flukes. I adjusted the scope back to the previous setting, or as close as I could get and opened the JSB Exact RS tin again. I shot the same way as before — relaxing before each shot. After 5 shots I could see that it was still good, so I went downrange and photographed the group just in case I blew it with the final 5 shots. I didn’t measure this group, and when I enlarger the picture I saw that it is horribly out of focus. But it’s proof for what I’m going to show you next.

S4000E first 5 shots
The first 5 shots of a 10-shot group. Sorry for the blur.

This group was not as small as the previous 5-shot group. It was more like the group from the previous day, but somewhat larger. I was still relaxing for every shot.

On the next 5 shots, though, something remarkable happened. I could feel in my off hand when the shot was ready to go. The rifle felt dead-calm in my hand and I knew the pellet was going to the right place. As a result, the final 5 shots did not change the size of the group. Ten shots went into 1.134-inches. But look at the group. Seven of the 10 shots are in 0.725-inches.

S4000E second 5 shots
The final 5 shots did not enlarge the group. It measures 1.134-inches between centers.


Gentlemen — the final 5 shots in this group are tighter because I am starting to learn how to shoot this rifle. That’s what happens when you have an accurate air rifle that requires a knack to shoot well. Once you learn the knack, you get consistently better.

Is the JSB RS pellet the only pellet that does well in the S4000-E? I doubt it. But each pellet goes to such a different place on the target that the scope has to be adjusted for every one. I learned that in Part 3, which you’ll see if you go back and read it again.

I did all this with a 4-power scope and I would also like to say that the scope that comes with the S4000E is extremely bright and clear at 25 yards. You will be able to use it as long as you wish. I could even see the .22 caliber pellet holes inside the black bull at 25 yards through this scope.

Is this a world-beater?

Is the Stoeger S4000E a world-beater bargain. Absolutely! Or, it’s not. You be the judge. If you want to become a better shot, this is the best value on the market today. But if you don’t like trying hard to do your best, better go with a precharged gun. I’m telling you right now, $150 buys a heck of a lot of airgun!


I have now tested the Stoeger S4000E as thoroughly as I can and I find it to be a great value. It’s powerful, accurate, has a smooth firing cycle and is easy to cock. But it’s a rifle you have to devote yourself to. It’s a rifle you have to get used to and be willing to learn how it works. I did that for you in the five parts of this report because I believe this is a rifle worth spending the time to learn. I was as transparent as I could be and showed you all my mistakes as I learned the rifle. Hopfully they will help those of you who decide to take the plunge and get one.

My thanks to Benelli USA for providing this rifle for the test. I hope they got as much out of these reports as you did.

Stoeger S4000E Black Synthetic Suppressed rifle combo: Part 4

by Tom Gaylord
Writing as B.B. Pelletier

Stoeger S4000E MGS
Stoeger S4000E breakbarrel rifle.

Part 1
Part 2
Part 3

This report covers:

  • Mount the scope
  • Sight-in
  • RWS Superdomes
  • Rested on the bag
  • H&N Baracuda Match with 5.53mm heads
  • Oh, oh!
  • First group
  • Sharper sight — second group
  • Superdomes again
  • Explanation
  • Summary

Today will be a different sort of report. I tested the Stoeger S4000E for accuracy at 25 yards.

Mount the scope

The scope that came with the rifle came with the rings already attached. Even the scope stop stud had been lowered on the rear ring by exactly the right amount. It took about one minute to mount the scope because so much had already been done.


I began to sight-in at 12 feet. It took three shots and I was on close enough (meaning the pellet struck as far below the aim point as the center of the bore is apart from the center of the scope’s optical path) to back up to 10 meters. There, I was almost perfectly on (meaning one inch low and centered left and right), so after two confirmation shots I backed up to 25 yards.

RWS Superdomes

I refined my sight-in and started shooting at 25 yards with the RWS Superdome pellet. I used the artillery hold I described in the last report (off hand touching the triggerguard) I would get three pellets that were close or even touching and two others that were far away. So I switched to holding the rifle like a deer hunter (grasping the forearm with the off hand and holding the rifle firm but not tight). Oddly, that seemed to work until it didn’t. I will come back to that in a bit.

Rested on the bag

Then I rested the rifle directly on the sandbag and was rewarded with three shots in 5 inches at 25 yards. Okay — that’s out! I even tried shooting with my off hand open under the cocking slot — in other words, far forward. But I still got wild shots.

So, after about 30 shots I switched pellets.

H&N Baracuda Match with 5.53mm heads

We all saw how accurate H&N Baracuda Match with 5.53mm heads were in Part 3. So I switched to them now. The groups were smaller, but they were still larger than they should be — especially after the Part 3 test results. And there were still wild shots.

Why it was almost like…

Oh, oh!

And that’s when it hit me — shots spraying wildly around like that. What would I tell you if you complained about that? I would tell you that your scope’s elevation adjustment was set too high and the erector tube was floating. Only I knew that this one wasn’t! I had the elevation dialed almost as low as it will go — and, yes, also far to the left. There was plenty of tension on the erector tube spring.

Only two other things could be wrong. The scope could either have moved in the mounts during shooting or it could have broken internally from the forward recoil of the rifle. I was paying so much attention to shooting groups that I hadn’t watched the orientation of the scope. So I looked through the scope and discovered that the elevation reticle was no longer straight up and down and centered on the spring tube. It had shifted 5 degrees to the right at the top and 5 degrees left at the bottom. Either the scope had twisted inside the rings or the erector tube has broken. Also, the scope adjustments now didn’t seem to move the impact of the pellet.

Stoeger S4000E shots
I fired 50+ shots trying to get the rifle to group. One target is missing from this picture. The rifle would put three pellets close together then spread out the other two. I used both pellets (Superdome and Baracuda Match) and all the holds that are described in the text.

I had been shooting for 90 minutes by this time and didn’t want to mount and sight in another scope, which would lake another half hour. So I removed the scope and shot the rifle with its open sights. I had been shooting with Baracudas at the time, so I continued with them.

First group

The first group was shot with a deer-hunter hold I mentioned earlier. For some reason that seemed to be the best for this rifle on this particular day. I was still wearing my normal glasses and the front sight was slightly blurred for this group.

The S4000E put 5 Baracudas into 1.74-inches at 25 yards. Now, I know that isn’t the best group, but look at it. Four of the five pellets are in 0.777-inches. That ain’t too bad! So I wondered what I could do if I could see the front sight better. As you know, seeing a crisp front sight is the key to real accuracy — not a clear target!

Stoeger S4000E open sight group 1
Shooting open sights and a deer-hunter hold tightened the group considerably. This one measures 1.74-inches between centers with the 4 on the right in 0.777-inches.

Sharper sight — second group

With my 1.25 diopter reading glasses the front sight sharpened crisply. The second group of Baracudas went into 1.378-inches, with 4 in 0.936-inches.

Stoeger S4000E open sight group 2
This group was shot with my reading glasses on. I could see the front sight more clearly. It’s five shots in 1.378-inches with 4 in 0.936-inches.

Superdomes again

Now it was time to try it with the Superdomes. Shot 1 was high and to the right, so I adjusted the rear sight down and to the left. Shot two was a 9 that’s close to the center of the bull. But the group? Oy!

Five Superdomes went into 2.417-inches at 25 yards. But those three that are together on the edge of the bull are in 0.481-inches. This is what the rifle had been doing all day and it’s indicative of a variation in the hold. Because it has a gas spring it is super-sensitive to the hold. However, once the right hold is found, rifles that show this kind of promise can become tack-drivers.

Stoeger S4000E open sight Superdomes
The upper right hole was made before the scope was adjusted for Superdomes. Five Superdomes went into 2.417-inches at 25 yards with three in just 0.481-inches.


The S4000E is telling me that it’s an accurate rifle and I just haven’t found the right hold yet. I think it’s some variation of a deer-hunter hold that I haven’t tried yet.

The rifle is also telling me that my eyes aren’t helping. Well, I have a solution for that! And it isn’t another scope. See if you can guess what I’m going to do next.


This rifle is telling me that it can shoot. I know today’s results don’t seem to support that, but I ask you to trust me. For the low retail price plus the accuracy we saw at 10 meters, I see a lot of potential. The S4000E is an incredible value and I want very much to see what it is capable of.

Air Arms S510XS Ultimate Sporter with Laminate Stock: Part 2

by Tom Gaylord
Writing as B.B. Pelletier

Air Arms S510XS
Air Arms S510XS Ultimate Sporter with Laminate Stock.

Part 1

This report covers:

  • Fill probe
  • First velocity test
  • High power
  • #3 power (one click down)
  • #2 power (two clicks down)
  • Low power (four clicks down — as low as the adjuster will go)
  • Discussion
  • Test 2 shot count
  • High power
  • Is there more?
  • High power
  • Magazine and feeding
  • Trigger pull
  • One last test
  • JSB Exact Jumbo Heavy
  • H&N Baracuda Match
  • Summary

Today we begin looking at the performance of the Air Arms S510XS Ultimate Sporter with Laminate Stock. This is the day we look at the power/velocity of this regulated PCP. The first order of business is to fill the 186cc reservoir to 250 bar. Reader Pelletpopper asked me to fill it with a hand pump to the maximum I was able, because Pyramyd lists a hand pump with this gun. I’m not going to do it. I’ll tell you right now I can fill it all the way, but after about 2500 psi it gets hard to pump. I see no purpose for filling by hand since I would never do it that way. If I wanted an inexpensive way to fill the rifle I would use the Nomad II compressor.

Fill probe

Air Arms pneumatics use a proprietary fill coupling. It works well but you have to have a dedicated hose or fit the adaptor with a male Foster fitting on the other end.

S510XS fill coupling
Air Arms fill coupling is proprietary.

S510XS fill adaptor
Air Arms fill adaptor is like no other.

First velocity test

How do you test a rifle that has adjustable power? My approach is to find out what it does on all power settings with a single pellet. That pellet will represent what it will do with other pellets at different velocities, because the relationship remains the same. Let’s see.

For this test I used the RWS Superdome because it’s medium weight and also pure lead. There is nothing to throw off the numbers. After the fill to 250 bar (tank gauge) the rifle’s built-in gauge read 240 bar. From here on I will only refer to the rifle’s gauge.

High power

240 bar start

210 bar remains.

The average for the first string on high power was 941 f.p.s. The spread went from 933 to 958 — a difference of 25 f.p.s. At the average velocity the Superdome pellet developed 28.52 foot pounds at the muzzle.

#3 power (one click down from the top)

210 bar start

175 bar remains

The average for this string is 929 f.p.s. It’s not that different than the first string at high power. The spread goes from 924 top 936 f.p.s. — a difference of 12 f.p.s. That’s considerably tighter than the high-power string and the power is very close. This is probably a better (more consistent) setting for the Superdome pellet when I want power. At the average velocity the Superdome developed 27.79 foot-pounds of energy.

#2 power (two clicks down)

175 bar start

160 bar remains

The average for this string is 836 f.p.s., which is a big difference from the last setting. This is a useable power setting. The spread ranged from 828 to 842 f.p.s — a difference of 14 f.p.s. So the rifle is consistent at this power setting. At the average velocity the Superdome pellet generates 22.51 foot pounds of energy.

Low power (four clicks down — as low as the adjuster will go)

160 bar start
4………did not register

150 bar remains

The average velocity for this setting is 297 f.p.s. In my opinion that’s not a useable velocity. The spread went from 279 to 306 f.p.s. — a difference of 27 f.p.s. At the average velocity the Superdome pellet generated 2.84 foot pounds of energy.


This rifle doesn’t behave like a regulated rifle. Instead it acts like it has a balanced valve. Three power settings are useable and two of them — the middle two — are the ones I would select for the Superdome. The top and bottom settings have too much velocity variation with this pellet. That matters because when we find the best pellet, we should zero the rifle at those two powersettings — or at least at one of them.

The discharge sound on all settings is very low for the power generated. On the lowest setting the rifle is extremely quiet. You could shoot this rifle in most small suburban backyards at any power level without attracting attention.

Test 2 shot count

I’ve fired 40 shots since the fill. The onboard gauge still reads 150 bar, which is in the green zone, meaning there are more shots available. For this test I dialed the power back to the highest setting.

High power

150 bar start

125 bar remains

The average for this string is 948 f.p.s. That’s 7 f.p.s. faster than the first string that was shot with the same pellet on the same setting. But look at how the shots all decline in velocity. The spread from this string is 56 f.p.s. That doesn’t look like a regulated rifle, does it? In fact I believe that at 125 bar the rifle has fallen off the regulator. That gives you an idea of how many shots to expect with this pellet from one fill — perhaps two magazines on high power and three on the setting that’s two clicks down from the top. At the average velocity for this string the Superdome pellet generated 28.94 foot pounds of energy.

What you should do is watch the onboard pressure gauge and refill when it gets to 125 bar. If you are shooting groups at distance (50 yards or more) refill at 150 bar.

Is there more?

Is the rifle really off the power curve? I fired 5 more shots to see what happened.

High power

125 bar start

Yes, the rifle has clearly fallen off the regulator. It’s time to refill the reservoir.

Magazine and feeding

The magazine functioned perfectly throughout these tests, but the sidelever did get stuck a couple times with each mag, having to be coaxed to go forward again. Once I learned that and came to expect it, I just powered through.

It is possible to double feed the rifle, so you have to watch what you’re doing. Also the magazine does not stop the bolt after the last shot, so watching the pellets feed is essential. Otherwise you’ll shoot blanks.

Trigger pull

The trigger is two stage and set up nicely by the factory. I will adjust it for you in the next report, just to tell you how it goes, but it’s working the way I like them right now.

Stage one takes 12 ounces and stage two averaged exactly 1 lb. 8 ounces. The pull is delightful and fully controllable. This is the kind of trigger I can work with!

One last test

My guess is that the JSB Exact Jumbo Heavy pellet will be the best in this rifle. I will test it now on high power to see what we get. For kicks I will also shoot a string with the H&N Baracuda Match pellet. This will give us insight into the true power potential of this test rifle.

JSB Exact Jumbo Heavy

High power
250 bar start (gauge on gun agrees with my tank gauge)

225 bar remains

This test was interesting, because there was no hesitation to feed the pellets. I think the Superdomes were the problem with that — not the rifle. the low is 870 and the high is 886 f.p.s., so a 16 f.p.s. difference. The average velocity is 879 f.p.s and at that speed the pellet generates 31.11 foot pounds of energy.

Now let’s see what the Baracudas do.

H&N Baracuda Match

High power
225 bar start

180 bar remains

The first thing to note is the lower use of air with these heavier pellets. Based on what I’m seeing here I think 30-35 full-power shots are possible.

The average velocity for this string is 829 f.p.s. At that speed the Baracuda generates 32.37 foot pounds. So Air Arms has hit the advertised power level. The spread went from a low of 824 to a high of 835 f.p.s. That’s an 11 f.p.s. difference. Also there was no feeding problem with Baracudas, either. It makes me think the S510 might do best with heavier pellets.


Now that I have a handle on the performance the next report will be about adjusting the rifle to suit me. For that I will need to mount the Meopta Optika6 3-18X56 RD SFP scope in the Sportsmatch 30mm high adjustable scope mounts that I’m testing in conjunction with this rifle. I hope to also report on both the scope and the mounts by that time. Stay tuned!

Stoeger S4000E Black Synthetic Suppressed rifle combo: Part 3

by Tom Gaylord
Writing as B.B. Pelletier

Stoeger S4000E MGS
Stoeger S4000E breakbarrel rifle.

Part 1
Part 2

This report covers:

  • Today’s goals
  • The test
  • Sight-in
  • JSB Exact RS
  • RWS Superdome
  • H&N Baracuda Match with 5.53mm heads
  • Shot cycle
  • Trigger
  • Hold
  • Trigger
  • Cocking
  • Summary

Today I start testing the accuracy of the Stoeger S4000E Black Synthetic Suppressed rifle. I will be testing with open sights today but remember this is a combo, and that’s what I really want to test. So today will be a shakedown to learn as much as we can about the rifle.

Today’s goals

There are a couple things I want to find out from today’s test. First I want to know which pellet(s) the rifle likes. That way I won’t waste any time when the rifle is scoped.

I also want to discover how best to hold the rifle. The S4000E has a gas spring and they usually make rifles hold-sensitive. Of all the rifles with gas springs I have tested, so far only the Sig ASP20 has not been hold-sensitive. So I began the test expecting this rifle to be sensitive and I was looking for the best way to use the artillery hold.

The test

I shot off the bench, using an artillery hold and resting my off hand on the sandbag. In case you aren’t aware, only a few air rifles can be rested directly on the sandbag and still be accurate, and it’s best to start your test thinking the rifle is sensitive to hold.

I shot 5-shot groups because I wanted to test as many pellets as possible. I used the open sights and, while I did adjust them as I went, I wasn’t looking to hit the center of the bullseye. I just wanted the group to be somewhere on the paper target.


Sighting-in the rifle turned into a longer test where I also searched for the right pellet and the best way to hold the rifle. I tried JSB Hades, Air Arms Falcons, and Air Arms Field pellets to no avail. The groups were too large to consider, but they did teach me something. This rifle shoots each pellet to a different location on the target. It’s so different that until I found the right pellets it didn’t make sense to adjust the open sights. But I did discover that holding my off hand back by the triggerguard is the correct way to hold the rifle. That set me up for the next discovery, which was finding the pellets that worked!

JSB Exact RS

The first pellet that made some sense (with the right artillery hold) was the JSB Exact RS dome, Five of them went into 1.09-inches at 10 meters, with three of them in just 0.339-inches.

Stoeger S4000E JSB RS group
Five JSB Exact RS pellets went into 1.09-inches at 10 meters, with three of them in just 0.339-inches. Not bad, but I bet it can do better.

While this group is okay, it isn’t great. But the three pellets that are close tells me that I’m holding the rifle correctly and perhaps the best pellet is soon to come. If you remember from Part 2 I discovered two pellets that seemed like they might work in this rifle. The obsolete Beeman Kodiak looked good, but when I tried it in the sight-in today I was using the wrong hold. Rather than go back and try it again, because I can’t get more when these run out, I switched to the other pellet that looked good in Part 2.

RWS Superdome

The RWS Superdome is the first good pellet I found for the S4000E. Five pellets went into 0.555-inches at 10 meters. When I saw this I knew the rifle was accurate, because remember that I’m shooting with open sights that are fiberoptic!

Stoeger S4000E RWS Superdome group
Now we’re talkin’! The S4000E put five RWS Superdomes into 0.555-inches at 10 meters. This is accuracy I can work with.

H&N Baracuda Match with 5.53mm heads

Remember those Beeman Kodiaks that I thought might be good? Well, the final pellets I tested were five H&N Baracuda Match with 5.53mm heads. These are the exact same pellets as the obsolete Kodiaks. They are just sold under a different name, and H&N gives us a choice of head sizes where Beeman didn’t. I picked up the tin of 5.53mm heads at random, and look what they did! Five pellets went into 0.438-inches at 10 meters, and that is with open sights. This rifle really can shoot!

Stoeger S4000E Baracuda Match group
Now, that’s a group! Five H&N Baracuda Match (5.53mm heads) went into 0.438-inches at 10 meters.

Shot cycle

Remember I said in Part 2 that this rifle is smooth? Well, it really is! I have now had my face on the stock for 55 shots and can tell you the rifle doesn’t slap — not even a little. It does lunge forward a little, but even that is under control.


I promised to report more about the trigger after shooting the rifle for accuracy, because that’s where I get the most exposure to it. The second stage on the S4000E has a long travel and it’s easier for me to think of the rifle as having a single stage trigger, because that’s how the second stage acts. I got used to it right away and once I did and once I found the right way to hold the stock, look at my results!


I have said a lot about the hold in this report. That’s more of a note to myself for the next accuracy test, which will be with the scope mounted. Yes, the rifle needs to be held with the artillery hold (stock rested on the open palm of the off hand with a soft grip all around to allow the rifle to recoil as much as it wants to), but it isn’t fussy at all. I got the hang of the hold pretty quick and you can see the results in the final two groups.


I cocked the rifle 55 times and can now report that it’s not that hard. The one thing that’s different is because the barrel comes down so far the rifle becomes a little hard to cock in the final few inches of barrel travel. That’s a geometry thing, and I found it easiest to use my other hand to boost the effort. I cocked it one-handed maybe 10-15 times and the rest of the time I used the second hand at the end of the stroke. I could have gone on to shoot another 55 shots with ease, doing it that way.


Gentlemen, we have a winner here! I can tell that even before mounting the scope. In fact it was beginning to look that way back in the velocity test. And, the beauty of it is, at $160 — this rifle is affordable! It has the power and accuracy we need and the smoothness to complete the package. Stoeger has done everything right — as several readers who own other Stoeger rifles mentioned in their comments to the first two reports.

Next up will be the test of the scoped right at 25 yards. I can’t wait!

Beeman C1: Part 2

by Tom Gaylord
Writing as B.B. Pelletier

Beeman C1
My new Beeman C1 is a .177.

Part 1

A history of airguns

This report covers:

  • Baseline
  • H&N Baracuda Match 4.50mm
  • RWS Superdome
  • RWS Hobby
  • Discussion 1
  • Trigger pull
  • Cocking effort
  • Discussion 2
  • Summary

The Beeman C1 I am testing is the airgun I acquired at the Texas Airgun Show this year. In Part one I noted for you all the shortcomings I could find with the rifle, which were many. These are the things I will address as this report advances. So, we will look at velocity today, but not accuracy until I straighten the bent barrel and tune the powerplant.


Today’s test will just establish where things are at this time. Now before we start testing, I want to say a few things. Reader David Enoch said he thought detuning this rifle to shoot a little slower might be a good idea. He was looking for a rifle that cocks easily. I hadn’t thought of that, but it doesn’t seem wrong.

The C1 doesn’t have an adjustable trigger. It’s a light trigger and we will find out how light this one is today. But a small rifle that’s accurate and easy to cock is a very nice thing. It’s the reason I like the Diana 27 so much. The C1 is larger than the Diana 27, but still small enough to be considered handy, so I’m going to give this idea some thought. Until we open her up and see what’s inside I really don’t know where we are yet.

Okay, let’s see what she’s doing today. This is a .177 caliber rifle that Beeman touted as an 830 f.p.s. airgun. We’ll see.

H&N Baracuda Match 4.50mm

I started with the heavy H&N Baracuda Match pellet with a 4.50mm head. This pellet weighs 10.65-grains and in the C1 it averaged 647 f.p.s. That produces a muzzle energy of 9.9 foot-pounds. The 10-shot string ranged from a low of 637 to a high of 655 f.p.s., so the spread was 18 f.p.s.

We know that in spring-piston airguns the lighter pellets are usually more efficient, so they should be slightly more powerful as the weight decreases. The C1 is a vintage spring gun that should prove the rule. Let’s see.

RWS Superdome

The 8.3-grain RWS Superdome was next to be tested. Ten Superdomes averaged 732 f.p.s. for an average muzzle energy of 9.88 foot-pounds. So the power “rule” doesn’t play out with this pellet.

The velocity ranged from a low of 722 to a high of 740 f.p.s. That’s a spread of 18 f.p.s. — again. Interesting.

RWS Hobby

Without a doubt the RWS Hobby was the pellet Beeman used to test the C1, back in the day. It was the lightest lead pellet generally available here in the U.S. at that time and was always used for velocity tests.

In the C1, Hobbys averaged 806 f.p.s. for 10 shots. That’s a muzzle energy of 10.10 foot-pounds, so the power rule holds true with this pellet. The spread ranged from a low of 793 to a high of 817 f.p.s. That’s a difference of 24 f.p.s.

Discussion 1

I am surprised this C1 is as powerful as it is. I would have bet against it, given how light the cocking effort seems to be.

There is a small bit of vibration with each shot, but by the standards of the day when the rifle was made it’s not much. We don’t have to put up with it today, and I don’t intend to, but I’m saying the powerplant may be in better shape than I imagined at first.

Trigger pull

The single stage trigger breaks at 3 lbs. 3 oz. It’s fairly crisp and has very little perceptible creep. I will look at the condition of the mating trigger parts and at least lubricate them when I’m inside the gun.

Cocking effort

The C1 has a strong chisel detent that requires a slap at the muzzle to open easily. You can break it with just your hands, but the slap makes it go faster. Once broken open the barrel is very loose and flops around. I do want to tighten the barrel pivot if I can.

The rifle cocks with 26 lbs. of effort. It should be about 35 lbs.  The cocking stroke is smooth all the way through. David Enoch, I think this rifle is what you want right now if I can fix those other things. If the mainspring is still straight I will leave it in the rifle. But if it’s canted I will replace it, because a canted spring causes buzz.

Discussion 2

I will be interested to see the piston seal, because the one in this rifle is made of Teflon. It doesn’t have a parachute lip; it’s just a solid white hockey puck.


This is as far as I can take the C1 before I straighten the barrel. So the next installment may take some time, because a lot of things might have to happen before I can write it.