by Tom Gaylord, a.k.a. B.B. Pelletier
The Tanfoglio Gold Custom Eric Grauffel pistol is a competition airsoft gun in a box!
Today is the day we adjust the BAXS in the Tanfoglio Gold Custom CO2 blowback airsoft kit gun to see how it affects the gun’s ablity to group. Remember, the BAXS is another form of hop-up, which is the generic name for a rubber bumper that puts a backspin on the airsoft BB as it exits the bore. That causes the BB to fly straighter and farther than it would if it were not spinning, or if it were allowed to spin randomly.
So, the first thing to do is to get to the BAXS adjustment wheel, which is located deep inside the gun’s slide. The gun must be partially disassembled, and therein lies a problem. The manual is poorly written and illustrated with confusing small photos that don’t depict what you actually must do.
To remove the slide of this pistol, the slide stop, or what the manual called the slide stopper, must first be removed. There are 2 different things that must be done precisely to get the slide stop out, and the manual doesn’t cover them. First, the slide has to be pushed back only about a quarter inch to release the slide stop. If you see the rear of the barrel dive down as you push the slide back, it’s moved too far. Second, there’s a very small clearance hole for the large end of the slide stop on the left side of the frame. Once again, pushing the slide too far back will cause the stop to pass this clearance hole, and the slide stop cannot be removed from the gun.
Of course, you don’t find out any of this until the slide is off the gun, which is too late. And the instructions are one sentence long. If you don’t know how to remove the slide, the instructions will not help you!
The slide must be removed to adjust the BAXS wheel.
Once the slide is off, the BAXS adjustment wheel is located on the underside of the slide and barrel assembly. It’s a small plastic wheel that’s turned by a small thin blade, such as a tiny screwdriver. A pin in the wheel limits its travel to less than half a turn, so the amount of adjustment is small. But if the gun was designed right and manufactured carefully, it should be enough to make a difference.
The BAXS wheel is turned to adjust the amount of backspin put on the BB. The adjustment is limited to less than half a rotation of the wheel.
I noted where the adjustment wheel was when the gun was disassembled. It was close to one end, so I moved it to the other extreme end. If there was going to be a difference, I wanted it to be immediate and visible. And it was — as I will now show you.
I decided to begin with the Air Venturi Pro CQBBs that weigh 0.25 grams because they were the most accurate in the previous test. When you adjust something as finicky as hop-up, stick to one BB whose performance you know. To do otherwise would just waste your time because you would never know if it was the particular BB or the gun’s adjustment that was right or wrong.
I shot a lot of targets in this test, but I’m not going to show you all of them. For the first couple, I was just getting the BBs back on target at 10 meters. The BAXS adjustment moved the point of impact several inches higher than it was the last time. But as I adjusted the dot sight and brought them back down onto the paper, I noticed something. They all tended to be strung out vertically, but were very tight horizontally. And each target, of 5 that I shot, had 4 BBs tight together and one that was apart from the group — a flier. Only there was no reason for the flier that I could see.
So, there were 4 BBs grouped together and the fifth BB would be more than one inch away from the main group. I adjusted the BAXS a couple times to correct this, but it persisted with this BB.
This 5-shot group measures 3.197 inches, but the lone shot at the bottom opens it up by more than one inch. Notice how narrow the group is.
Another 5-shot group of 0.20-gram Air Venturi CQBBs is also tall and even narrower. This time, 4 BBs went into 1.08 inches, and the fifth shot opened the group to 2.26 inches.
There were 3 more groups just like these, and then I decided to switch BBs. The next BB I tried was the 0.20-gram Marui Black that Pyramyd Air does not stock. Being lighter, these BBs went faster than the others. The first group was really tight.
Here are 5 shots in 0.847 inches at 10 meters. The Tanfoglio seems to like the 0.20-gram Marui Black BBs. This is what a good airsoft pistol can do at 10 meters.