Posts Tagged ‘airgun’
by B.B. Pelletier
Kevin is responsible for this special Part 4 report on the Gamo Rocket IGT .177 breakbarrel. He pointed out that I didn’t give the rifle enough of a chance to excel in the accuracy test, and several of you agreed. Even Edith chimed in when she read Kevin’s comment. In light of the leniency I have shown the recently tested Hatsan springers, this is certainly true. I won’t change my normal way of reviewing airguns, but in this instance I can see that it makes good sense to try other pellets in this rifle.
It takes a long time to shoot a 10-shot group, so I resolved to shoot just 5 shots per pellet and see where that left me. If the five were reasonably close, I would complete the group with the other 5 shots.
First up was Kevin’s favorite, and a pellet I’ve found to be accurate in a variety of air rifles — the JSB Exact RS dome, which weighs 7.33 grains. I was prepared to be surprised by the accuracy, but RS domes delivered 5 shots into 1.29 inches at 25 yards. So I stopped shooting them. I remembered that the lighter pellets did worse in this rifle in the last test, so next I tried the heavyweight Beeman Kodiak pellet.
The first Kodiak pellet went way to the right of the aim point, then the next one about an inch to the left of that. After that, the pellets went to the same place until shot 6, when the pellet went back to the right. Some time in the final 4 shots, 2 pellets went to the right and low. How do I interpret this?
Kodiaks gave me this group. Six of the 10 shots are nicely grouped, but 4 others open the group considerably. This 10-shot group measures 1.257 inches between centers. The smaller group of 6 measures 0.635 inches.
This group made me wonder if I was being consistent enough with the Rocket IGT. Did I “season” the bore with enough pellets before shooting the group? I actually didn’t season it at all, but the fact that the last Kodiaks are as wide of the large group as the first one makes me think seasoning isn’t important here.
Was I holding the gun as carefully as I should be? That was a real concern. I hadn’t put a scope level on the gun, but was I completely relaxing and then shifting the crosshairs back to the target like I should?
Bottom line, I wanted to see another group of Kodiaks. That would perhaps tell me what I needed to know.
Ten more Kodiaks went into this group that measures 1.906 inches between centers. Eight of those pellets went into 0.784 inches — a group size that I think represents the true accuracy potential of the Rocket IGT.
The second group is very revealing. I tried just as hard to shoot well as I had with all the groups before, and there were no called fliers, but you can see from this group that some pellets didn’t want to play along. That tells me I’m probably not doing something consistently, and it’s affecting the results.
I tried one final group of 10 Crosman Premier heavies, just to see what another heavy pellet might do. This time, the 10-shot group was better than both groups of Kodiaks; but at 0.984 inches, it wasn’t as good as I’d hoped. The openness of this group makes me think that this is perhaps not the pellet for the Rocket IGT. But I’m not sure of that, either.
I’m going to give the Rocket IGT a fifth test, and this time I’m going to do everything I can to make it shoot well. I’m going to mount a more powerful scope, sort the pellets by weight, mount and use a scope level, and spend the time I need to shoot the finest groups possible.
You may not realize it, but it takes a LOT of time to shoot the absolute best you can. It takes me about 5 minutes per shot when I’m really working the artillery hold. I want to do this for this rifle because, in this test, I see the potential trying to peek through. Normally, the shooting I already did would be enough to make a decision.
If you think what I’m about to do is overkill, consider this. I shoot hundreds of different air rifles every year and never have the chance to get familiar with any of them. An owner who has just one rifle can, over time, become so familiar with that rifle that he can shoot like I am about to, but do it in far less time. But if I do take the time to settle in for each shot and if I do remove all of the accuracy-destroying variables, we will finally see what this rifle can really do.
Don’t think that I’m going to do this for every airgun test from now on. I’m doing it this time because Kevin and the other readers were right. The Rocket IGT needed more of a chance to shine; and when it got that, it showed the glimmer of a rifle that wants to shoot.
by B.B. Pelletier
I shot the Gamo Rocket IGT .177 breakbarrel air rifle to see how potentially accurate it is. This is the day many readers have been waiting for. I was even nipped in the hocks by one reader to get it done faster.
The scope on the test rifle is the 4×32 fixed-power scope that comes in the package. The optics are clear, but at 4x, the image seems small. The crosshairs are also rather coarse. So, you really have to pay attention when aiming. I would say this scope is okay to start with if you don’t want to spend more money. And since the Rocket IGT has no other sights, you’ll need an optical sight of some kind.
Starting the test
I decided to use the same four pellets that were used in the velocity test. The distance was 25 yards and all shooting was done indoors, so weather wasn’t a problem. The first pellet tested was the JSB Exact 10.3-grain dome that delivered velocity in the low 800s. The group started very well. Around shot five, it had opened to twice its size. By the end of the session, it was double that. The 10-shot group measured 1.074 inches between the centers of the two widest shots.
It’s always best to evaluate the trigger when shooting for accuracy because you notice every little nuance while trying to hold the reticle still on the target. I now discovered that stage two of the new Gamo trigger has a long perceptible movement. I won’t call it a creepy trigger, but you certainly do feel it move as the sear gradually disengages.
So, my evaluation of the trigger changes from great to just good. It’s certainly the best trigger Gamo has ever fielded; but at the same time, it’s no Rekord.
Back to the test
I felt that JSB pellets were teasing me, and they really wanted to shoot better, so I would come back to them, but next came RWS Hobby pellets. Three shots went into three inches and they were through. Hobbys are not the right pellet for the Rocket IGT.
Next up was our new friend, the H&N Baracuda Green. I expected them to shock me with their accuracy after all the recent success we have seen. But the first group wasn’t that good. It measures 1.141 inches between centers, and you will see that it is more vertical than horizontal.
Since I’d now shot two vertical groups, I decided to try a differtent hold. Instead of placing my off hand at the rear of the forearm where I could feel the triggerguard, I moved it forward under the cocking slot. Then, I shot another group of H&N Baracuda Greens. This group measures the same 1.141 inches as the first group, but it’s even more vertical than the first.
At this point, I stopped shooting and checked all the stock screws. All were loose, and the two in the forearm had to be tightened quite a lot. When I returned to the bench, the point of impact had changed — and H&N Baracudas no longer grouped very well. Four shots went into 1.50 inches, and I just stopped shooting.
It isn’t supposed to work like that. Tightening the stock screws is supposed to give you the best groups the rifle is capable of; but with the Rocket IGT, that did not happen — at least not with Baracuda Greens. However, something told me to try the JSB pellet again, so that’s what I did.
The next group of JSB Exacts was shot with my off hand against the triggerguard and the stock screws tight. This time, there was a lot less walking of the pellets, and I ended up with a fairly good group of 10. It measures 1.025 inches between centers and is much rounder than any of the earlier groups. This is the best group shot during this test and is probably a good representation of what this rifle is capable of.
Gamo PBA pellets
I couldn’t do this test without giving Gamo’s PBA Platinum pellet that came with the gun a try. So I shot two of them. They cracked like a .22 long rifle in the house and landed seven inches apart. That ended the test!
What do I think about the Gamo Rocket IGT? Well, it has many good things going for it. Light weight. Easy cocking and a good trigger are the main ones. The power is also reasonable.
On the minus side, the accuracy I saw was mediocre at best. But I only tried four pellets in the rifle. Who’s to say there isn’t a good pellet that would make this rifle shine? It only needs one.
by B.B. Pelletier
Let’s look at the power and velocity of the Gamo Rocket IGT .177 breakbarrel air rifle. You learned in Part 1 that the numbers printed on the box and gun were in disagreement with the Gamo USA website and Pyramyd Air’s site, but it turns out that 1,300 fps is the correct velocity according to an email Edith received from Gamo’s vice president of sales. Well, Edith spotted yet a third velocity claim — this time on the end flap of the box. A sticker listed the velocity as 1,000 f.p.s., with no further explanation. We’ll clear all of this up and find out just how fast this rifle really does shoot.
I remarked in Part 1 that the cocking effort of the rifle seemed low for a gas spring, which is what IGT (Inert Gas Technology) means. My guess was the rifle cocked at between 30 and 35 lbs. of effort, which is a good 10 pounds less than other gas springs that generate similar power. My bathroom scale confirmed that the test rifle cocks with just 33 lbs. of force, making it easier than most gas springs. The piston stroke is quite long, which is how they manage to generate all that power from such an easy-cocking powerplant. I applaud Gamo for using the physics of the gas spring in this creative way.
I also remarked that the new Gamo Smooth Action Trigger or SAT, as they call it, is a large leap forward from any Gamo trigger I have ever tested. It’s adjustable via a hard-to-access Phillips screw located behind the trigger blade; and when I attempted to adjust it, I discovered that it was set by the factory to the best position.
Screwing the adjustment screw clockwise reduces the stage-two pull length and counterclockwise does the reverse. The screw was in as far as it would go, but I did unscrew it a full turn and verified that it does increase the second-stage pull length.
The trigger released at 4 lbs., 4 oz. with good consistency. The first stage is very light (just one ounce) and stops positively at stage two. This is the kind of sporting trigger that will please many shooters, and I’m so glad to be testing it.
The last comment on the trigger is that Gamo has made the safety entirely manual. The blade is in an usual (for Gamo) place, but it doesn’t go on when the rifle is cocked. I see that as a positive step toward customer satisfaction. Gamo has somebody who knows how to design airgun triggers.
And now to the principal business of the day. I tested the Rocket IGT with four pellets — two made of lead and two that are lead-free. The first pellet tested was the JSB Exact 10.34-grain dome — a heavy pellet for a .177. With a gas spring, there’s no coiled steel mainspring to worry about, so the question of whether this heavy pellet is suited to a spring-piston powerplant is moot.
The JSB Exact pellet got an average velocity of 822 f.p.s., which was below the estimate of 900 f.p.s. I made in Part 1. The velocity spread went from a low of 816 to a high of 828, so a 12 foot-second spread over 10 shots. That’s very consistent. At the average velocity and using weight of 10.34 grains, this pellet generates 15.52 foot-pounds of muzzle energy.
Next up was the H&N Baracuda Green — the new lead-free pellet that’s surprising us with its accuracy. And that’s why I tested it here — because I intend to try it out in the accuracy test, as well. They averaged 1100 f.p.s. on the nose, and the range went from a low of 1092 to a high of 1105 f.p.s. So the spread was a tight 13 f.p.s. At the average velocity, this 6.48-grain pellet averaged 17.41 foot-pounds. That’s good power for this rifle; and if these are accurate at 25 yards, they’ll be a good hunting pellet for rabbits, squirrels and similar game.
Following the Greens, I tried Gamo’s PBA Platinum pellet, a 4.7-grain lead-free dome that they pack with the rifle. This is the pellet they say will go 1,300 f.p.s. (although Gamo’s website still says 1,250 fps). In the test rifle, this pellet averaged 1,229 f.p.s., but the string was large. It ranged from a low of 1,214 f.p.s. to a high of 1,242 f.p.s. The spread was 28 f.p.s. While that’s not terrible, it’s noticeably greater than all other pellets that were tested. At the average velocity, this pellet generates 15.77 foot-pounds at the muzzle.
The rifle comes pretty close to the 1,250 f.p.s. claim still listed on Gamo’s site (as we write this) — but not the 1,300 fps they claim on the box and rifle.
The last pellet tested was the venerable RWS Hobby. This 7-grain lead pellet is often the fastest of its type. In the Rocket, they averaged 1,004 f.p.s. with a spread from 996 to 1,013 f.p.s. The spread was 17 f.p.s., and this pellet generated 15.67 foot-pounds of energy at the muzzle. Once again, the Gamo rifle met its advertised velocity with lead pellets.
Observations thus far
Gamo met the advertised velocity for lead pellets but was below the advertised velocity for their Platinum PBA pellets. Their Inert Gas Technology gas spring is easy to cock and doesn’t vibrate much when fired. And their new Smooth Action Trigger is performing just as nice on this rifle as the mockup in the Gamo booth did at the 2012 Shot Show.
I think you can sense my approval of this air rifle so far. It’s completely modern and nothing like the guns I usually favor, but it cocks easily, it generates the power it’s supposed to, is lightweight and has a fine sporting trigger. If it turns out to be accurate as well, I think Gamo has a fine new rifle in their lineup.
by B.B. Pelletier
Back when I reviewed the 2012 SHOT Show, I showed you several new innovations that Gamo was bringing to the market this year. This rifle, the Gamo Rocket IGT .177 breakbarrel, contains the first of those I will test. I’m testing rifle serial No. 04-1C-138639-11, for those who wish to keep track.
One of the new technologies is in the title of this air rifle. The IGT stands for Inert Gas Technology, which is Gamo’s term for a gas spring. The gas spring replaces the conventional coiled steel wire mainspring with several improvements. It’s lighter in weight, doesn’t vibrate as much when fired, is resistant to cold, and can remain cocked for long periods without suffering any degradation. Compressed gas doesn’t fatigue like steel spring stock.
The second technology in this new rifle is the Smooth Action Trigger, or SAT, as Gamo calls it. It’s a two-stage trigger that’s so much better than Gamo triggers of the past that it deserves its own blog. The aluminum blade is well-shaped and vertical; so when it’s pulled, it comes straight back and doesn’t rotate upwards into the stock. The two stages are very clearly separated and stage two is quite crisp. I will say a lot more about it in Part 2 when I test rifle’s velocity.
The two technologies that the Rocket IGT does not have are the Bull Whisper barrel — a polymer-jacketed barrel with internal baffles — and the Shock Wave Absorber (SWA) recoil pad that helps dampen recoil. Since the Rocket IGT is not a super magnum rifle, I guess it doesn’t need either of these. But Gamo advertises this rifle at 1,300 f.p.s. while shooting .177 non-lead PBA pellets, so it’s no slouch. That velocity is printed on the outside of the box as well as on the spring tube of the gun. On the Pyramyd Air website, the velocity is listed as 1,250 with PBA ammo…and that’s also what Gamo advertises on their website. Either way, that’s a lot of power. I would think we could see some of the heavier accurate lead pellets go out the muzzle in the 900 f.p.s. range, which would be ideal. [Note from Edith -- I'm checking with Gamo on this discrepancy, but I suspect it's 1300 fps.]
This is a lightweight, slim air rifle. It weighs just 6.1 lbs. due to the use of synthetics in the barreled action and a synthetic stock. It harkens to the days of the Shadow 1000 and, more recently, the Whisper. Unlike the Whisper, this rifle has no baffles at the muzzle. Even so, the discharge sound isn’t that loud. It’s a solid three on the PA sound scale, but it’s not objectionable.
I haven’t been able to keep my paws off the gun since taking it from the box, and I can tell you that the initial shooting impression is a good one. First of all, even though it has a gas spring, I’m estimating that the cocking effort doesn’t exceed 35 lbs., and I wouldn’t be surprised to see it closer to 30. A gas spring exerts full pressure from the moment it’s first compressed, so you notice the cocking effort a lot more than with a coiled steel spring — but this Gamo is very nice in this respect.
The piston stroke is extra-long, which is where the power comes from. When you break the barrel to cock the gun, it folds down to within just four inches of the triggerguard. That means the cocking link is going far to the rear, pushing the piston into lockup with the sear; and that, in turn, means a long piston stroke.
The trigger is two-stage and very crisp. Old-timers will not recognize it as a Gamo trigger. It’s also adjustable, and I plan to evaluate it in Part 2.
The gun fires without a lot of recoil or vibration. It seems to have a lot of power, but we’ll find out for sure in Part 2. One thing I definitely love is the non-automatic safety. It’s there for you to apply — or not — as you choose, but you’re not forced to take it off before every shot. Bravo for Gamo!
More impressions of the rifle
The stock is slim and fits me quite well. It’s entirely ambidextrous, with a raised cheekpiece on both sides of the Monte-Carlo profiled butt. The pistol grip has a slight swell on both sides. Nothing about the rifle favors a right-handed shooter over a southpaw, which is a big plus in its favor.
The synthetic material the stock is made from is cool and slightly rough to the touch. The butt sounds solid, which I know will be appreciated by most shooters. The pistol grip and forearm are both slightly roughened where the hands want to grip.
The barrel is a thin steel tube surrounded by a fluted synthetic jacket. That’s become a Gamo trademark in recent years. Though I don’t care for the aesthetic, it does keep the weight off.
Surprise at the muzzle!
I casually glanced at the muzzle to examine the crown and was surprised to see no rifling inside the barrel at that point! Using a magnifying hood and a tactical flashlight I can see that the rifling ends considerably before the end of the barrel, like almost an inch deep. So, there really isn’t a crown to this barrel, just what could be called a counterbore at the muzzle. Unlike a true counterbore, the rifling just ends without a step in the barrel. The pellet is free to fly on its own at this point. What it will or won’t do for accuracy remains to be seen, but I’m intrigued!
There are no open sights, nor are there provisions for them. This rifle is meant to be scoped and comes with a Gamo 4×32 scope in rings that are ready to mount. The base clamps to 11mm dovetail grooves cut into the spring tube, and a single vertical scope stop hole is provided. The rings mount with a Torx wrench that’s provided, and both the base screws and cap screws use the same wrench, which is a big plus. The caps have two screws apiece. I had the scope on, leveled and adjusted for my eye relief in less than 10 minutes.
Gamo has been advancing their air rifle technology greatly over the past decade. This year they’ve hit the afterburners! This new rifle looks right, feels right and has a great trigger. Let’s hope it’s also accurate. If so, the Rocket IGT could be a home run for Gamo.