Benjamin Marauder PCP .177-caliber air rifle: Part 2
by Tom Gaylord, a.k.a. B.B. Pelletier
This is a look back at an air rifle that has become iconic throughout the world — the Benjamin Marauder. The last time I looked at this rifle, I did it in my conventional way. This time I’m doing it different because I know more about the rifle.
My goal this time is to tune the Marauder exactly as I want it to shoot. I think there will be a great benefit for those who want to learn about PCPs to watch this as it develops. Today, I’ll test the rifle for velocity in the conventional way, except I won’t do a shot count — not today.
In the next report, I’ll test the rifle for accuracy at 25 yards, only I’ll stack the deck by selecting the pellets that I believe will be the most accurate. The accuracy test will tell me which one(s) to select. After that, I’ll test that one pellet for velocity and for the total shot count I can get.
Then, I’ll decide what I want that pellet to do. If it’s a heavyweight, I’ll try for moderate velocity in the 850 f.p.s. range and then try to get the greatest number of shots from it. If it’s a medium or lightweight pellet, I’ll probably dial the velocity back to about 900 f.p.s. and try for the best shot count.
I’ll also be interested in the fill pressure. If I can get 25 good shots with 2,500 psi air, I won’t care that 3,000 psi air gives me 31 good shots with the same pellet. But if 3,000 psi gives me 38 good shots compared to 25 good shots with 2,500 psi, then, yes, I’m going to set the gun up to fill to 3,000 psi.
As I do all of this experimentation, I’m going to document it so those who have questions about the Marauder can see how it works. You tell people today that an air rifle has adjustable velocity, and they expect to see a rheostat on the side of the stock; but the Marauder isn’t like that. It’s a thinking man’s airgun. You set it and forget it. You don’t keep fiddling with the controls until it’s a jumbled mess. We’re going to spend the time to learn how to do it right.
But wait…there’s more! Not only does the Marauder allow you to adjust the velocity of the pellet, it also lets you adjust the maximum fill pressure of the air reservoir. When you hear that, you probably wonder why anyone would bother with a fill pressure other than the maximum — which in the case of the Marauder is 3,000 psi. Here’s why they do it. Some owners may use hand pumps that they find difficult to use above 2,500 psi. Other owners may use scuba tanks, but they live 40 miles from the dive shop and want to be able to use their rifle for a longer time than conventional wisdom permits. For these owners, adjusting the maximum fill pressure to 2,500 psi makes perfect sense. They understand that they’ll get fewer shots at maximum velocity when the fill pressure is lower — just as you understand that you can’t go as far on a gallon of gas as you can when the tank is full, but you can go just as fast.
When you’re adjusting the velocity and the maximum fill pressure, you have to find a balance point between the two. That’s what’s confused many people. The Marauder is the first air rifle in the world to allow both the fill pressure and the velocity to be adjusted. It’s like they’ve given you your very own NASCAR engine, and it’s up to you to tune it for the race track you’re going to drive on.
One pellet is all I want
I don’t care to discover 27 different pellets for this rifle. I only want the single best one. I don’t care how much it costs — only how accurate it is and how effective (power and shot count) I can make it. So, that’ll take some time to locate and some more time to set up the gun to use that single pellet most effectively.
That’s what I intend doing. The first step is to test the rifle for velocity now. I plan to test the following pellets:
I may not have included your favorite .177 pellet on my list, but allow me to explain my thinking. First, all of these pellets are domes. I know the domed pellet to be the most accurate pellet shape on the market. And each of the pellets I selected to test are known by me to be very accurate.
I selected the Beeman Kodiak, but I’ve found that the Beeman Kodiak Match, H&N Barauda and H&N Baracuda Match are all the same pellet, as far as performance goes. I use them interchangeably, so I only have to test one to know how all four perform.
There may be other pellets that are better in the Marauder; but starting from zero, these pellets are the ones I would choose. Let’s see how they do.
Crosman Premier heavy
Crosman Premier heavies averaged 943 f.p.s. with a spread that went from 941 to 945 f.p.s. That’s right — only 4 f.p.s. separated the fastest and slowest shots! At the average velocity, this pellet makes 20.74 foot-pounds of energy at the muzzle.
Crosman Premier lite
Crosman Premier lites averaged 1,015 f.p.s. The low was 1,012 f.p.s. The high was 1,018 f.p.s., so 7 f.p.s. was the total velocity spread. At the average velocity, this pellet produces 18.08 foot-pounds of energy at the muzzle.
JSB Exact Heavy
JSB Exact Heavy pellets averaged 936 f.p.s. The low was 932 f.p.s. and the high was 940 f.p.s. The total spread is 8 f.p.s. At the average velocity, this pellet produces 20.12 foot-pounds of muzzle energy.
JSB Exact RS
JSB Exact RS pellets averaged 1,032 f.p.s. The spread went from a low of 1025 f.p.s. to a high of 1039, so a total spread of 14 f.p.s. At the average velocity, this pellet makes 17.34 foot-pounds of energy at the muzzle.
Of all the pellets tested, RWS Superdomes were the most difficult to load into the magazine. I had to use a pusher to get almost every pellet into the mag. They averaged 1,014 f.p.s. and went from a low of 1,008 f.p.s. to a high of 1017 f.p.s. Total spread was 9 f.p.s. At the average velocity, this pellet produced 18.95 foot-pounds of energy at the muzzle.
Beeman Kodiaks averaged 957 f.p.s. in the Marauder. The high was 960 f.p.s and the low was 955 f.p.s., so the spread was 5 f.p.s. Kodiaks produced an average 21.66 foot-pounds of muzzle energy.
Where are we?
I just dumped that data on you so I could get to this discussion. What do these numbers tell us? They tell me my rifle is set up extra-hot. I have no need for all that speed; so after I find the right pellet, I plan to dial back the power to between 850 and 900 f.p.s. If the best pellet is light, I’ll let it go toward the 900 f.p.s. side of that range. If it’s a heavy one, I will try to get it down to around 850 f.p.s.
Why would I do that? To get additional shots per fill. The way the rifle is now set up, I’m wasting air. Not that too much air blows out with every shot, but I just don’t need these pellets to go so fast, to do what I want them to.
Did you notice?
I was impressed by how tight the shot strings were. Remember, the Marauder doesn’t have a regulator. It’s doing all this with just a well-balanced valve. We’ll want to keep that in mind when it comes time to make adjustments.
The magazine is superior!
There have been a lot of negative comments on the Marauder’s spring-loaded magazine. I can shed some light on that. I’ve watched some new owners who were befuddled by how this magazine works, and they ruined it by forcing it when it didn’t do what they expected it to. My magazines are several years old and with hundreds of shots run through each of them. I’ve never had a single problem. But force them even one time to do what they weren’t designed to do, and you’ll ruin them. This mag is a copy of a successful UK PCP magazine, and that one had the same learning curve problems.
My test Marauder is very quiet! Even operating at the high power level it’s at right now, it’s extremely quiet. I don’t know if it’ll get even quieter when I cut the power, but I do plan on observing and reporting.
More about the stock
The Marauder stock is not as clunky as people say. In fact, the pistol grip is thinner and narrower than most UK PCP stocks. The forearm is wide, but only enough to contain the large reservoir.
I’m ambivalent about adjusting the trigger because the one on my rifle is so sweet that I don’t want it to change. It’s exactly where I want it to be. Theoretically, I can always adjust it back, but I’ve seen too many instances where the theory didn’t pan out.
The 2-stage trigger breaks at less than 11 oz. The first stage is 9 of those ounces, so the release is very light and glass-rod crisp. Only the addition of an overtravel stop would make it better.
I knew what the Marauder was like before this test began. That’s why I’m testing it the way I am. I get to learn something new, and people who are interested in the Marauder get to see it in a way they probably haven’t seen anywhere else. I think the Marauder is a classic for all time, but you have to decide that for yourselves.