Diana’s Nemesis Part 2

Diana’s Nemesis Part 2

Webley chases the Chaser

By Dennis Adler

The Nemesis is Desert Eagle sized, which is big for a CO2 pistol (maybe not for a Webley) with an overall length of 10.25 inches, an overall height from the base of the grips to the top of the rear sight of 6.0 inches but a surprisingly light weight of 2.0 pounds.

Did Webley go to school on Diana’s Chaser or is the Nemesis just a coincidence? Given manufacturing lead time, probably neither, since the technology isn’t exclusive to Diana or Webley, and the presentation of both the Chaser and Nemesis is quite different. The Chaser is a clever design with its detachable shoulder stock and interchangeable barrels, breech blocks, and sleek target shooting (and small game hunting capability in .22 caliber) design. The Nemesis is more like a Desert Eagle; big, imposing, and designed for straight up plinking and target shooting with a decent capacity of 14 rounds in .177 caliber using the 7+7 tandem rotary magazine. This is a gun built for serious paper punching.

For a big pistol the Nemesis is just a hair over 1 inch in width, not counting the bolt lever or the addition of the tandem rotary pellet magazine. The red and green fiber optic sights are very easy to pick up and hold on target. The use of fiber optic sights is growing exponentially throughout the firearms world, not just with air pistols.

Sizing it up

Despite its magnum-sized appearance, the polymer frame and slide-like upper receiver, hold the weight down to a modest 2.0 pounds. The overall length from the threaded muzzle to the back of the receiver is just shy of 10.25 inches, with an overall height from the base of the grips to the top of the rear sight of 6.0 inches, and a width (not counting the tandem rotary magazine or bolt handle) of 1.0625 inches. This is pretty narrow for such a big gun. Adding the magazine and bolt handle, the rear width increases to 1.875 inches. It is a hand-filling pistol that you can get a firm grip around and hold on target. With a copious 8.25 inch sight radius and zero recoil effect when fired, this is a pistol that should punch bullseyes all day long.

The tandem rotary pellet magazine has the back of the pellets facing out on the off side, which looks a little odd, but the idea is to pull the mag out, rotate 180 and reinsert on the reload. With the bolt locked back it takes about 3 seconds to do.

In my hand, the grip, which is 2.25 inches at the palmswell and 1.875 inches at the top, allows my trigger finger to easily rest on the trigger and my thumb to overlap my middle finger. This is an almost ideal hold with the finger grooved frontstrap, slight beavertail of the grip frame, and deep thumb rest. With the reversible bolt handle it is all ambidextrous and overbuilt like a Webley should be.

Like the Chaser, the Webley looks like the CO2 should go into the pistol grip, but it is inserted horizontally into the CO2 chamber under the barrel. The base of the grip slips out and has the hex head tool to unscrew the seating cap in the lower receiver.

The 12 gram CO2 cartridge slides in, and the seating cap threads back on easily, unlike the problems some threaded CO2 caps have. You can barely hear the CO2 cartridge being pierced. I used a drop of RWS Chamber Lube on the tip of each CO2.

Velocity checks

The Nemesis is factory (Webley) rated at up to 420 fps. This does not specify the grain weight of the pellet or the ambient temperature when the chronograph test was done. But it would be safe to say it would have been an indoor test done at the factory at an ideal temperature. That is how I will be doing the velocity test, indoors at a temperature of 72 degrees. To get the maximum velocity for the first test I am using Sig Sauer Match Ballistic alloy wadcutter pellets with a weight of 5.25 gr. Velocity test two will be with H&N Sport Match Green 5.25 gr. alloy wadcutters, and test three with 7.0 gr. RWS Meisterkugeln Professional Line lead wadcutters.

What I discovered as I shot the velocity tests is that the pellets need to be seated with a stylus so the rims are about a 16th of an inch below the leading edge of the chambers. If you push them in too far they fall out the other side, so you learn quickly how deep to seat them. This improved velocity and consistency of velocity from shot to shot. The H&N Sport Match Green alloy pellets (loaded) produced the highest average velocity of 473 fps, better than 50 fps over the factory rating with lead pellets.

With a fresh CO2 the Nemesis kicked the first three shots downrange at an impressive 485 fps, 495, fps and 475 fps, and then velocity began to settle in to the mid 400’s to average 444 fps. This seemed like a pretty significant drop in velocity for only seven rounds with a fresh CO2. I decided to shoot it over with another seven Sig Sauer Match Ballistic alloy wadcutters. This time my average velocity settled in at 420 fps. A little low for alloy pellets. My first thought about this was whether or not how the pellet was seated in the rotary magazine could have an effect on velocity. I seated each at about the same depth just below the rim of the pellet chamber. Some pellet magazines need to have the pellet seated a little deeper. To test this I loaded another seven and used a stylus to seat them further into the chamber so there was a clear space between the rim of the pellet and the chamber. This slight change produced an average velocity of 435 fps but more importantly with velocity ranging from 448 fps to 431 fps, much more consistent than the first two velocity tests. So, no harm done by seating the pellets a little deeper into the chamber and better overall consistency from shot to shot. This is how I loaded pellets for the remainder of the test.

Left-handed shooters, this is your bolt action pellet pistol! After locking the bolt to the rear, you will find a hole going through the back of the bolt. Insert a small metal tool, like an Allen wrench, through the hole and loosen the bolt turning it counterclockwise. Then unscrew it from the front half of the bolt and remove it. The bolt handle will be loose inside the channel…

…rotate it so the flange is lined up to the channel and pull it out. Turn the gun around and reinsert the bolt handle on the right side channel, turn it so the flange is vertical and put the bolt back into the channel and through the flange. Screw the bolt back in until it is finger tight and lightly tighten it using the same tool.

In about a minute you have a left-handed gun. That’s got to be worth something! The gun is shown with the single shot pellet tray inserted. Here you can also see the dovetailed channel rear sight which is held by a locking screw on either side.

At 21 shots into the CO2, and Webley states an average of 40 shots per CO2 (agreeably a low number of total shots), I ran test four with H&N Sport and velocity for the Match Green alloy wadcutters started off with a first shot at 500 fps! Now, this was shot number 22 on the CO2 after letting the pistol sit for about 10 minutes while I was writing notes. The remaining six shots were fired at 30 second intervals, beginning at 485 fps for shot number 23. My average velocity for all seven shots ended up being 473 fps; with shot number 28 clocking 494 fps. Obviously, the H&N Sport Match Green was performing better in the Nemesis than the Sig Sauer and this was half way through the CO2’s performance expectancy according to Webley. Now, what about heavier, 7.0 gr. lead wadcutters? Starting with shot number 29 on the original CO2 cartridge, the Meisterkugeln averaged 422 fps, right on spec with the Webley factory numbers. Given that result I went back and ran seven Sig Sauer alloy wadcutters through the gun to see where performance had fallen. In the interim, I had also done some outdoor photos and run the gun another seven times, so I was starting on shot number 37 with expected drop off by round 40 (again according to Webley). The velocity started off at 469 fps, and by shot number 40 was beginning to drop into the low 400s and by the seventh round had settled into the high 300s with the last round clearing the chronograph at 361 fps for an average velocity of 404 fps for seven shots, and that is with lightweight alloy pellets. Webley is right; you are going to get about 40 shots with the Nemesis before performance begins to drop off.

In daylight, the fiber optic sights are about a bright as if they were battery powered. Picking up the target and holding the sight picture is a snap and with zero recoil this gun is made for bullseye target shooting.

After around 40 shots with the rotary magazine I can attest to it being easy to load (actually a little less awkward than the Chaser rotary mags) and the bolt action on the Nemesis is so smooth it is almost effortless to rack in the next round in the rotary magazine.

In part 3, we will see how well this comes together at 10 meters using all three brands of test pellets.

6 thoughts on “Diana’s Nemesis Part 2

  1. Mine comes in today, FedX… This gun has it all, CO2, .177 Pellet, Rifled Steel Barrel, Bolt Action, Reversable Bolt, Single Shot, Magazines, Picatinny for Laser, Dovetail for Reflex, Fiber Optics Front &Rear, Grip Handle storage, Adjustable Trigger, Threaded Barrel Front with Cap, Thanks for the Heads Up Dennis, I also have the Diana Chaser & the Crosman 2300T so Comparisons will be in Order and Forthcoming…


  2. TheChaser was a pleasant surprise and a best buy. This one may be a better choice for lefties if accuracy is as good. With the tube under the barrel air system , maybe it is time for a retro Crosman 600.


  3. OK … Stuck a Utg Laser on the Webley yesterday & sighting in using the Single shot, tried the Magazine and it turned out to be a colossal PIA, tricky to load, tricky to install to the breech & line up with the bolt, will not be using it at all…everything else on the gun is outstanding, the 2 stage trigger is a marvel, 1/8″ take up then about 8oz pull, not crisp but mushy…will get an exact measurement this morning…don’t know accuracy yet will find out this AM, gun has good feel very comfortable in hand more later…


  4. Update…Removed the Utg Laser in favor of the Trijicon Reflex Red Dot (Actually a USA made Clone) so same as my Diana and Crosman…huge improvement for Sighting, I now have all 3 Bolt Action Single Shots shooting within a few thousanths of each other Center to Center 5 Shot Groups at 7 Meter’s Sitting and Bench Rested to a Caldwell Rabbit Eared Bag, shooting Crosman Destroyer Pellets…Remeasured the Trigger and it is 1/8″ to 3/16″ 1sst stage Take up then to a Soft 8oz 2nd stage Break, very, very good Target Trigger…still shooting Single Shot not bothering with the poorly fitting Magazine, a serious QC problem for Webley IMO…..I consider the Nemesis an Entry Level 10 Meter Air Pistol and only $120.00…….c’mon……I highly recommend this as a BA,SS Target Pistol….thanks again Dennis for the Heads Up and Comparison to the Diana Chaser, good job and you can stay another week…..


  5. OK Another Update… I remeasured my Nemesis Trigger Pull and this is what I get and this is a Factory Setting as far as I know….2 Stage Trigger measured to the end of 1st Stage is 8 Oz then 2nd Stage Pull is another 8 Oz to the Break…this is a total of 16 Oz total pull…I am used to gently pulling thru to the end of or stop of the 1st stage then holding to my POA then the final 8 oz to the break…This is easily the Best Air Pistol Trigger action of my collection also for additional creditation of my experience I am an ARA 50yd and 100yd BR Precision 22LR shooter and have a Jewel Trigger set at 2 Oz in my Rem. 40X and have shot other BR Rifles with Trigger Pulls thru 2lbs…..This is all FWIW info….


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