Terminal accuracy with a pellet firing pistol Part 1

Terminal accuracy with a pellet firing pistol Part 1

The limitations of a rifled barrel revolver

By Dennis Adler

As good as it gets with a 12 gr. CO2 powered handgun, the 4.5mm Umarex Colt Peacemaker with 7-1/2 inch barrel can actually hold its own against a .45 Colt out to 50 feet.

This is a test I have been waiting to do because pellet firing pistols (not competition target pistols) but CO2 BB magazine and cartridge-loading designs like the Colt Peacemaker, Dan Wesson Model 715, and Sig Sauer P226 and P320 semi-autos, are generally limited to ranges of 21 feet to 10 meters (33 feet). Beyond that velocity and accuracy begin to diminish. This is the accepted norm often referred to as “the nominal distance for blowback action semi-autos and pellet-firing revolvers.” As my latest comparison between the rifled barrel Colt Peacemaker and smoothbore Schofield single actions demonstrated, 10 meters is where smoothbore and rifled barreled pistols begin to go their separate ways. The rifled barrel pistol, however, maintained a tight group out to 10 meters, and this raises the question, “How far can a pellet fired from a rifled barrel revolver or semi-auto pistol travel before its effective accuracy declines?”

The Umarex Colt Peacemaker (shown in the deluxe Adams & Adams nickel plated, hand engraved edition) has proven to deliver unrivaled accuracy at traditional 12 gr. CO2 pistol shooting distances of 21 feet to 10 meters. But what is this 7-1/2 inch rifled barrel Single Action really capable of?

Taking the 7-1/2 inch Peacemaker out to 15 yards

To begin this study I am starting with the most accurate pellet cartridge-firing single action revolver on the market, the Umarex 7-1/2 inch Colt Peacemaker. I have already established higher than factory rated velocities by firing cast alloy wadcutters instead of lead, so once again Sig Sauer Match Ballistic alloy pellets will be used. The target is simply a large cardboard backstop on the pistol range with a single red dot as a POA, and the gun will be fired offhand using a two-handed hold.

For the range test the Umarex Colt Peacemaker was loaded with lightweight 5.25 gr. Sig Sauer cast alloy wadcutter pellets to achieve the highest velocity, which averaged 423 fps. (The Umarex Peacemaker is factory rated at 380 fps).

Stepping back to 15 yards is only 12 feet further than 10 meters, so it will be interesting to see how much the groups open up. A second test will then be shot from 25 yards using a rested position. There is no question that a pellet will travel much further than 25 yards but its velocity, trajectory and accuracy are rapidly diminishing as it travels downrange. And remember, we are only talking about rifled barrel pellet-firing revolvers and semi-auto pistols with average velocities between 350 fps to 400 fps. These comprise an entirely different category of airgun from higher-powered break action or pre-charged pneumatic 4.5mm pellet firing rifles and pistols (including some very expensive competition models) capable of superior accuracy and velocities better than double those of 12 gr. CO2 powered revolvers and blowback action semi-autos.

Putting western gear aside, except for the John Bianchi Frontier Gunleather holster, the 15 and 25 yard shooting testes were fired using a modern two-handed hold. The longer range test was done sitting at the shooting bench with elbows rested on the table.

Peacemaker Scores

There is theory and then there is practical experience. At a range of 15 yards (45 feet) the Peacemaker did not lose significant accuracy, groups only opened up slightly. Point of aim had to be raised approximately two inches, whereas at 10 meters the sights were almost on POA. I was pleased to find that my groups from two separate 6-round sets were almost identical with a spread of 2.0 inches. I had four out of six shots more closely grouped and two flyers, which opened up the total spread. Of the closer four-round groups the measurement at 15 yards (45 feet) averaged 1.0 and 1.24 inches. This compares favorably to the Peacemaker’s six-round groups at 10 meters (33 feet) which measured 1.1 inches. At this distance the Peacemaker is still a pretty accurate wheelgun with alloy pellets.

From 45 feet out my 6-round groups average 2.0 inches with four out of six shots averaging 1.0 to 1.24 inches apart. (The red dot was my reference point for sighting)

Next I just about doubled the distance, from 15 yards to 25 yards to see what happens to accuracy. With calm winds, a heavy overcast and a temperature of 61 degrees, this second this test was shot from a rested position (two-handed hold, elbows on the shooting bench but no sandbag). Starting with the same two-inch hold over (which I used as a baseline for correcting), I quickly found my shots hitting at the bottom of the target board. The necessary hold over went from around two inches at 15 yards to 18 inches at 25 yards and accuracy went out the door. The spread on target opened up to 5.2 inches for six shots. Thus 25 yards is beyond the Peacemaker’s best accuracy. Having said that, all six shots were on the target and that means that you can hit a silhouette-sized target at 25 yards with a 4.5mm alloy pellet fired from a rifled barrel air pistol, just not with any precision.

What happened between 15 yards and 25 yards is the result of decreasing velocity and pellet trajectory, the laws of physics weighing in on a 5.25 gr. alloy wadcutter traveling at around 400 fps. From a sandbag rest I could probably tighten up the group by another inch, but 25 yards is simply where accuracy begins to decline with the rifled barrel 7-1/2 inch Peacemaker.

Yep, that’s me about 7 years ago doing a shooting test in Guns of the Old West with a .45 Colt caliber 7-1/2 inch and 3-inch pair of F.lli Pietta Single Actions. The test distance was 15 yards (45 feet) and average groups with Ten-X 165 gr. RNFP cowboy loads were 1.5 inches. Now I can shoot that same distance with a 7-1/2 inch Colt Peacemaker air pistol!

The real upshot of this test is that at 45 to 50 feet you can still shoot the pellet cartridge-loading Peacemaker with relative accuracy, and that’s a fair shooting distance for real .45 caliber Colts. Not bad for a 12 gr. CO2 powered Single Action revolver!

Part 2 will be Round 2 with a corresponding test using the new Sig Sauer P320.

A Word About Safety

Single Action airguns provide the look, feel and operation of their cartridge-firing counterparts and this is one reason why they have become so popular. Airguns in general all look like guns, these two Western models even more so, and it is important to remember that the vast majority of people can’t tell an airgun from a cartridge gun. Never brandish an airgun in public. Always, and I can never stress this enough, always treat an airgun as you would a cartridge gun. The same manual of operation and safety should always apply.

46 thoughts on “Terminal accuracy with a pellet firing pistol Part 1

  1. My experience with the 7 1/2 barrel Peacemaker is that it is the most accurate airgun I own. I have put 12 rounds through the same hole firing weaver stance at around 25 -30 feet. I have used 7 gr Meisterkugeln and Crosman 7.4 wadcutters. Will try the alloys next for accuracy. I have felt that the Peacemaker if it had the valve recalibrated for the US market could hit well over 500 fps , giving it 50-60 foot range and accuracy. Would be interesting to try the Webley for distance with the alloy pellets since it is the velocity champ with alloy pellets and its’ accuracy rivals the Colt, if only we could get a hold of a British rifled version. Then again a rifled barrel Schofield would be a contender.


    • I’m not sure if the Peacemaker can be recalibrated to produce 500 fps velocities, but I am looking into it with Umarex. Rifled barrel Webley models may yet arrive on our shores, so stay tuned on that. At 45 feet I am pretty happy with the accuracy of the Peacemaker 7-1/2 inch model. Given more time and practice I’m sure I can get tighter groups since the shots seem to be hitting pretty hard. I will try this test again later from a bench rest at 45 feet and see how the gun performs by eliminating the variables created by shooting offhand.


  2. Why stop there, how about a Buntline Special that twelve inch barrel would really push those SIG pellets. How about an accessory stock as well. The Wyatt Earp association would be a great marketing theme.



  3. Always overstating the obvious here. Some thing I find intriguing is the difference in grip designs various countries and regions used on their pistols. Comparing the Colt grip to the Mauser, with a Webley, or Nambu thrown in there were a lot of different ideas floating around back then.


    • And there were variations by the same makers on grip design, take for example the change Colt made when they introduced the 1877 and 1878 double action models with a bird’s head grip. Also consider the redesigned grip and backstrap of the Colt Bisley model of the Peacemaker. When S&W built the No. 3 American (and later versions) for the Russian military contract the grip design and triggerguard were both completely changed to suit the requirements of the Russian military. So this is a constant throughout history with changes in grip design and shape. We still see this today with continually changing grip contours and angles on semi-auto handguns.


  4. Adjusting valve flow and hammer impact can increase velocity. Hard hitting pellet revolvers would open up the door to western action air matches on reactive targets at 10-15 yards. A lot more affordable than even rimfire22 .Could be done almost anywhere.Now where is that lever action 177 Winchester 73?


  5. Here is another suggestion . The Umarex Peacemaker already uses an 1860 Army grip frame . Use that as the basis for an 1851 Navy percussion revolver loading 177 pellets from the front like a percussion revolver with a rammer, then use a rebated cylinder and make a 1860 Army in 22 cal . The old Crosman SA 45 revolver did this in the past .




      • Umarex should be offering more Peacemaker aftermarket grips . Shiny black like buffalo horn, mother of pearl , stag, checkered fleur de lis in ivory and wood, for starters



        • Do you have the Umarex Colt commander pistol? The round headed pin that goes into the right hand side of the slide release continues to pop out on my gun.


          • What do you mean by pop out? The round end protruding through the right side of the frame just below the slide is the opposite end of the slide release lever on the left. Its shaft passes through the barrel lug and out the corresponding opening on the right side of the frame. The slide release and the round headed pin you refer to is all one piece. Removing the slide stop/slide release lever from the left side of the frame is part of the gun’s disassembly. The round end is supposed to protrude slightly from the right side of the frame, but it is not part of the slide, assuming we are talking about the same thing.



  6. Ok while we’re dreaming how about light weight .410ish barrel liners for a Dbl barrel 12 gauge. A 12 gauge shot shell size hpa reservoir with a hammer activated dump valve. A chamber on the end holding shot that mates to the barrel liner with a forcing cone that screws on so the reservoir could be filled with a screw on foster fitting.



  7. Yes that’s it, when it pops out after shooting a few rounds it looks like a push pin. So it appears to be purely aesthetic, I just didn’t want to make it semi-permanent in case it needed to come apart for disassembly. So I’m going to use blue loc-tite to secure it. If that doesn’t work then super glue to the rescue. Thank you Dennis.


    • Don’t make it permanent, it has to come out to disassemble the 1911, which you may need to do sometime in the future. How long have you had this gun? Might need to take a trip to Umarex for a repair. It should not be coming loose on its own. The slide release locks into a notch on the frame when the gun is assembled and has to be removed in order of the steps in disassembly the same way. It doesn’t just pop out on its own unless the slide release lever is damaged and not locking into the frame.


  8. The old Crosman Peacemaker and SA 45 both loaded 22 pellets from the front with finger pressure, you could do this with a rammer that doesn’t put too much pressure. I used the old domed pellets or wadcutters with no deforming. I still have two functional pistols , will send a picture


    • Yes, a .22 caliber domed pellet would be more rugged. Not sure what kind of velocity you would get with a 12 gr. CO2 pushing a .22 pellet down a rifled barrel. The idea is sounding more and more interesting though.



        • That wouldn’t be too bad, but there are other issues with front loading a pellet into the cylinder chambers, and there would have to be a visual compromise, because unlike a recessed barrel so the gun has a proper muzzle size, you can’t recess the cylinder chamber so the opening would have to be the size of the pellet since there is no cartridge to carry the pellet inside. Then again, you have that same concession with .22 LR conversions of .36 and .44 caliber black powder pistols using drop-in cylinders and barrel liners like the Kirst Konverter. So, theoretically it could work with a 4.5mm or .22 caliber cylinder chamber to put the pellet right up to the forcing cone. Personally I’d rather see an 1851 Navy or 1860 Army cartridge conversion that uses the existing Colt rear-loading pellet shells. The bigger idea, of course, is to scale that up to a .22 caliber pellet without sacrificing too much velocity. Lots here for manufacturer’s to think about. Great input everyone!


  9. Maybe a valve equivalent to those used in the 2240 modifications. And if the front loading must be avoided there is a solution. Extra large nipples that can accept a pellet. I think I could live with this compromise.


    • I have actually discussed that idea before with manufacturers and it is one possible option if they were to make an 1851 Navy or 1860 Army in a cap-and-ball configuration. In fact, I like that approach better. That would not require much alteration to, or possibly no alteration, of the current Peacemaker design lower frame and internal operation, only barrel, cylinder and of course, loss of the topstrap, but operationally nothing mechanical, more of tooling new exterior parts to work with an existing system. It is mostly consumer demad that would drive this idea forward.


    • Why avoid front loading? That would keep it true to design and loading ,and it was done before . The only difference would be co2 from the grip frame rather than sent back from under the barrel


      • I agree100% but mr Adler’s opinion is well respected so more options come to mind.
        One practical reason for the “nipple solution” might be higher velocities if we take into account the results of front loading vs back loading cartridges.


Leave a Reply