Two aspects of the performance of the Nitro Piston were evaluated. First, it was necessary to determine pellet velocity, but here a problem was encountered. My wife and I travel in the western mountain states during the summer. This year, one of my special traveling companions was the Nitro Piston so the testing was conducted at high altitude, and the range where the Nitro Piston was tested is at an elevation of 5,500 ft. At this altitude, cocking any break action rifle draws less air into the compression chamber in front of the piston so when the gun is fired the velocity is lower. Previous testing has shown that at 5,500 ft the velocity is approximately 94% of what it is at an elevation of a few hundred feet. The .177 Nitro Piston gives velocities up to 1000 ft/sec and the .22 caliber gives up to 800 ft/sec. These velocities would be obtained at low elevation with pellets of light weight. However, these velocities will not be realized at high elevation with pellets of normal weight. With the chronograph in place, I fired a string of Crosman Premiers across it and got an average velocity of 631 ft/sec. When this value is corrected for the elevation factor, the velocity would be 675 ft/sec with a pellet weighing 14.3 grains. With pellets weighing about 11 grains, the velocity would be approximately 770 ft/sec which is close to the advertised value. Keep in mind that this was with a new gun and that performance generally improves after a break in period.

With Crosman Pointed pellets the average velocity was 625 ft/sec, with the Crosman wadcutter it was 623 ft/sec, and with Crosman domed it was 637 ft/sec. Keep in mind that at low elevation these velocities would be 40-50 ft/sec higher. As a result, the Nitro Piston would generate about 14.5 ft lbs of kinetic energy which means that it is a “magnum” airgun that is entirely suitable for hunting small game and pests.

Because accuracy is of paramount importance with an airgun, the Nitro Piston was tested with several types of pellets by firing three or four 5-shot groups at a distance of 25 yards. The average group sizes obtained are as follows: Crosman Premier, 0.91 inch; Crosman pointed, 0.77 inch; Crosman wadcutter, 0.89 inch; and Crosman domed, 0.80 inch. Keep in mind that these groups were fired outdoors at a range where there is always a prevailing breeze from a rifle that did not have an extensive break in period. Under better conditions, these groups would shrink to perhaps 0.5-0.7 inch. Therefore, it is clear that the Nitro Piston has plenty of accuracy to be an effective game and pest rifle.

Now with that said I also Bought a gamo big cat to make my setup up complete and I loved the light weight and speed of the Gamo. But it has one problem, The light weight is because it has light weight parts in it. The rear bushing was made out of a substance that resembled Plastic, but it might have been soft Aluminum. Any way the spring warped right off the bat, and the power ring blown through when the gun dieseled so that pretty much put my light weight Gamo out of business.
The daisy is about 15 years old, I bought it new and it has performed flawlessly since new, But the draw back is that is is a slow shooter, I’ll guess about 450 to 500 FPS using Corpsman Hollow points. The multi pump is the same age as the Daisy and it has been an on the mark 77 caliber since new, The only draw back is that you have to pump it up every shot.
So I use them all to keep them smooth and accurate.
They are my toys.
I can’t shoot my High powered rifles around the house because they are real loud and I don’t want to cause a disturbance, but my pellet guns do just fine on anything I want to run out of the Yard.
Any way ,, they are all good and Ive never accept the Gamo have had a problem with them. So i recon it’s just a preference when you go into the woods or sit on the porch and shoot flies off of the barn, which you can do quiet easily with a little practice and a good scope, which I have,,.
Have fun pick one, if it isn’t what you want it will still do the job that most will do. Hope this helps.. I have number 123 in the Marauder that benjamin came out with I got it from Airgun Depot, and it has shot virtually one hole groups at 20 yards, with a few pull offs that was my fault, the gun will shoot as good as the shooter..
Good day and Happy airgunning,,

Realistically, 1000 and 800 will most likely be the true fps.

-AJ

Gamo is known to advertise false velocity readings. It’s sad to see they’re still luring in people to believing their ridiculous claims.