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Education / Training Crosman’s Mark I Target pistol: Part 2

Crosman’s Mark I Target pistol: Part 2

by Tom Gaylord
Writing as B.B. Pelletier

Crosman Mark I
Crosman Mark I target pistol.

Part 1

A history of airguns

This report covers:

  • Loading the CO2 cartridge
  • O-ring material
  • Velocity
  • RWS Hobby
  • Air Arms Falcons
  • Crosman Premiers
  • Discussion
  • Shot count
  • Trigger pull
  • Summary

Today we look at the power of my Crosman Mark I Target pistol. This will be interesting because I don’t remember ever doing it. I probably did, but without a report to read I can’t remember.

Loading the CO2 cartridge

Usually on a CO2 pistol that stores the 12-gram CO2 cartridge in the grip, one of the grip panels comes off to remove and install the cartridge — the left one, more often than not. Not so with this pistol. Instead there is a large knurled cap at the bottom of the grip that is removed, and the cartridge inside slides out. If there is still significant gas in the gun, the pressure will force the o-ring in the cap to seal the cap tight and it may not rotate. Don’t use pliers to force it! Shoot the gun until the gas is gone or almost gone.

Crosman Mark I CO2 cap
The cap with the lever for piercing is the most common on the Marks I and II.

Crosman Mark I CO2 cap out
Here is the cap out of the gun. The o-ring that looks brown now was cream-colored when it was installed. Years of contact with Pellgunoil have changed the color.

There is also a later second type of CO2 cap. Instead of the lever it has a large button that you press in to pierce the cartridge. Crosman recommended pressing it against something hard, like a table, and it was covered in rubber to both not slip and also not mar the table. As near as I can tell it came out in the mid-1980s and is the less common type of piercing system. I suppose collectors like to have guns with this cap to complete their collections, but if you shoot the lever is much better.

Crosman Mark I CO2 cap lever forward
Here the lever has been rotated forward to pierce the CO2 cartridge.

Crosman Mark I CO2 cap piercing pin
The piercing pin is inside the cap. The lever moves it down (up in this view) to pierce the cartridge.

Crosman Mark I CO2 cap button
This button piercing system replaced the earlier lever system in the 1980s. It is less common than the lever and also a little harder to use. Photo provided by reader Halfstep.

I must confess that I thought the button piercing cap was older than the lever type, but reader Halfstep informed me that it was actually later. I researched it in several old catalogs and Shooter’s Bibles and discovered he is right.

O-ring material

Now, learn something about the material of which o-rings are made. Sometimes the material is permeable, which means the gas can be absorbed into the material of the ring which then swells up and keeps pressure on the cap for hours after the gas inside the gun has been exhausted. This problem doesn’t occur with modern o-rings because they are made from material that is impermeable to CO2. You don’t run into this often today, but 40 years ago it was common. Nearly all those older guns have been resealed by now, so if there is still a problem it’s because some owner used a hardware store o-ring made from gas-permeable material.


I will test velocity on both high power and low power for the same pellets. I’m only going to shoot 5 rounds on each setting, because a gas gun shouldn’t vary that much. And I will wait at least 10 seconds between every shot.

RWS Hobby

First up were RWS Hobby pellets. I expected them to be the fastest and they were. On high power they averaged 463 f.p.s. The low was 456 and the high was 466 f.p.s., so a spread of 10 f.p.s. At the average velocity the pellet generated 5.67 foot pounds at the muzzle.

On low power the Hobbys averaged 326 f.p.s. The spread went from a low of 312 to 333 f.p.s. That’s a range of 21 f.p.s. At the average velocity with this power setting Hobbys generated 2.81 foot pounds at the muzzle.

Air Arms Falcons

Air Arms Falcon pellets averaged 453 f.p.s. on high power. The spread went from 452 to 456 f.p.s., so just 4 f.p.s. between the low and the high. At the average velocity this pellet generated 6.12 foot pounds at the muzzle.

On low power the Mark I shot Falcons at an average 313 f.p.s. The spread went from 306 to 316 f.p.s., so 10 f.p.s. difference. At the average velocity on this power setting this pellet generated 2.92 foot pounds at the muzzle.

Crosman Premiers

I’m shooting a Crosman classic air pistol, so of course I have to test it with Crosman Premier pellets. On high power they averaged 437 f.p.s. The low was 435 and the high was 441 f.p.s., so a spread of 6 f.p.s. At the average velocity the muzzle energy was 6.07 foot pounds.

On low power Premiers averaged 296 f.p.s. with a spread from 290 to 301 f.p.s., which is 11 f.p.s. At this average velocity the pellet generated 2.78 foot pounds of energy at the muzzle.


The pistol is about where I expected it to be — low to mid-400s on high power with light- to medium-weight pellets. Now — what about the shot count?

Shot count

To this point I had fired the gun 30 times on one CO2 cartridge. Half of that was on high power and half was on low. That’s 15 shots on high power and 15 on low. That might compute to about 20-22 shots on high power. So I went back to Hobby pellets and started shooting again. This time it was all on high power and all Hobbys. I will begin this test with shot number 31.

50…………….462 the liquid CO2 is gone
66…………….347 stopped

This string shows the performance of CO2 quite well. As long as some liquid CO2 remains inside the cartridge to evaporate into gas, the velocity remains in about the same place. The moment the liquid has all evaporated, the velocity starts dropping and never recovers. That’s why we say CO2 is self-regulating. As long as it remains at a consistent ambient temperature, it acts like a pressure regulator.

So — how many shots do you get from a cartridge? That would depend on whether you are shooting on high power all the time, low power all the time or a combination of both power levels. Before conducting this test I would have guessed there were about 45 shots at consistent velocity on high power, which is about what we see here. Remember that 15 of the first 30 shots were on low power.

This pistol was resealed years ago by Rick Willnecker and it seems to be about where a new Mark I should be. Beyond that I can’t say anything because other Mark Is have either gotten tired and may need a rebuild or they may have been souped up by a tuner.

I would also like to point out that there are several more shots on this cartridge than I shot. Looking at the rate at which the velocity is dropping I would guess around 10 or so. I don’t like to shoot absolutely every possible shot from a gas gun because you run the risk of sticking a pellet in the bore. But the Marks I and II are single shots that are quite easy to clear.

Crosman Mark I breech
Looking down on the open breech we can see that it is easy to push out a stuck pellet with a rod inserted through the muzzle. Tuners will thin the pellet probe at the end of the bolt to make more room for gas to flow.

Trigger pull

I tested the gun the way it was set up, and when it is set on high power the trigger pull is 11 ounces for stage one and 4 lbs. 5 oz. at the break point of stage two. I thought stage two was breaking at two pounds, because this trigger is a crisp as a breaking glass rod.

On low power there is only a stage one and the trigger breaks at 1 lbs. 15 oz. the way the gun was set up. That’s good, but I don’t normally shoot on low power. I wanted to adjust the trigger to see if I could get the high power stage two let-off any lighter.

I screwed the Allen screw in (clockwise) and got a two-stage (high-power) let-off of 1 lb. 6 oz. It remained glass-crisp. The single stage (low power) pull went to 2 lbs. 3 oz. I can live with that all day!


Well, that is a good look at my Mark I that I believe is representative of most Crosman Marks. Next comes accuracy and I can’t wait!

author avatar
Tom Gaylord (B.B. Pelletier)
Tom Gaylord, also known as B.B. Pelletier, provides expert insights to airgunners all over the world on behalf of Pyramyd AIR. He has earned the title The Godfather of Airguns™ for his contributions to the industry, spending many years with AirForce Airguns and starting magazines dedicated to the sport such as Airgun Illustrated.

94 thoughts on “Crosman’s Mark I Target pistol: Part 2”

    • Siraniko,

      There was no room to reply to your comment about the regulator on my Onix Sport. Thanks for responding. I seem to remember that as well, now that you have mentioned it. I hope you are right, but I will be keeping it no matter what. It is just too accurate. Do you know if it’s harmful to adjust a regulated gun with air in the reservoir?

      Manigong Bagong Taon to you as well.( did I pick out the Happy New Year part?) I don’t know if i’m pronouncing that entirely correctly, but the way I’m saying it is fun!! I have forgotten. Where do you hail from, again?


      • Half,

        I don’t believe it’s harmful. Although it might be safer if degassed. Cumbersome though to repressurize then depressurize to do the checking.

        I’m in the Philippines BTW.


  1. Hajimoto posted a nice video review of the new Gauntlet .25 caliber a few days ago. He gets a little deeper into the inner workings of the rifle than most other reviewers. A couple of things I found particularly interesting. One was the cracked air stripper, and two, the fact that the .25 barrel OD is the exact same size as the .22 barrel OD.

    A Happy and Healthy New Year to everyone!

    • Geo
      That’s funny he mentioned that about the air stripper on the end and of the barrel. It looks just like the one the Marauder rifles use. Probably different dimensions with out me having a Marauder at hand right now.

      But I had 8 different Marauder rifles in all 3 calibers. And guess what. Out of those 8 guns two of them had that same piece cracked. And I called Crosman when that happened on the two different occasions. Each time they mailed me one no charge. And they was out of warranty even.

      What I wonder is will Umarex do the same.

      But man did you see that flat shot string his .25 Gauntlet got before he started messing with the different mods on the gun. Wasn’t as good once he made the modifications. Was not bad. But not as good as before the modding.

      Live and learn as they say. Some times it is best to leave well enough alone I suppose.

  2. Crosman started replacing the lever type cap with the button one after many guns were returned by owners that reported they were malfunctioning, but in actuality they were piercing the cartridge, and forgot to flip the lever back to retract the piercing pin to the shooting position.

    I love these guns and own more than I should.

    • On all of my mk1&2’s the low power position has a little creep in the trigger compared to the high power position which has a great trigger.

      You can adjust the power screw to a lower setting, and shoot on the high power cocking position for the better trigger..

      For me, the low cocking settings are used for close in plinking when power is not a factor, and shot count is, or when you are dispatching small pest at close range when you don’t need/want over penetration.

      The high power settings (where I sight mine in for) is for longer range shooting, and where full power is needed.

      High power consumes more gas, so shot count suffers.

  3. B.B.,

    I agree, there is no way the cartridge can escape on this pistol even if you got the cap off with a pair of pliers. It looked like this pistol though. I am pretty sure my cousin had to remove the left grip. We had some good times and quite a few adventures.


    • If the cartridge still is under pressure, you can either:
      A. Shoot it down.
      B. Grasp the cocking knobs and pull them rearward to open the valve and vent the remaining gas.

      You should NEVER have to use pliers on these guns..

        • Co2 pressure has to be low for this degassing method to work. Saves yourself from a bunch of dry firing to empty.
          A side note, it is good to cock the hammer prior to pressurizing a new co2 cart, no wasted gas
          I love my 1st Gen Mk1, never letting this one go
          Setup for indoor shooting now, BB you should remember this pistol from the PA Cup.

              • GF1,

                No rail on the original.

                I haven’t forgotten about the Onix pistol. Was still doing Chrismas family stuff on Sat. and I shot 64 different pellets and I knew you would want pictures of the groups. It takes a while to sort through, plus I have to follow the current blog. I want to know all I can about these guns. I’ll get it posted, though.


                • Halfstep
                  Looks like Erockrocket says a modded scope rail.

                  And also waiting for some shooting results from your Spanish pcp pistol. It was Spanish if I remember right wasn’t it.

                  And no hurry. Whenever you get to it.

                  • GF1,

                    I’m done with enough of the testing on my Onix Sport pistol to post some results. The gun is made by Snowpeak in China and goes by a lot of names. I bought mine from a retailer in Madrid,Spain and it was about $233 delivered. It’s .177 cal and its the full power version. There is a UK friendly version that is limited to under 6 FPE. Giles on Airgun Gear reviews that one in .22 cal, I think. At one point when I was playing with the adjustments I had the gun set up over 12 FPE. It is now at about 8.5 to 9 FPE.

                    The darn thing has adjustments for everything. The regulator is adjusted with an Allen wrench inside the trigger guard. The transfer port is adjustable from the top of the breech block. Pull off the grips and the hammer preload can be set. Trigger is 2 staged and adjustable for length of the first stage through a hole in the trigger guard and with the grip removed the sear engagement is supposed to be adjustable with an Allen wrench. I haven’t messed with that yet. My trigger has a very short 1st stage and breaks at 1.6 lbs according to my digital fish scale. 🙂 The book that came with my gun is all Spanish and doesn’t really even have much in the way of illustrations for you to work from either. I searched every way I knew how for an online English version with no luck and asked for help from the guys that read this blog, but I must be the only owner ’cause none came forward. I ended up finding a YT video review done by a Spaniard and recorded his audio track with my Google Translate app and it translated it well enough for me to find the adjustments and know what they were for. I will still appreciate any help I can get from you guys. In Europe and the Middle East there is a folding shoulder stock that looks easy to install and looks good on the gun.

                    Out of the box the gun acted like an unregulated PCP, slowly climbing then dropping abruptly after reaching its peak. I wasn’t even sure if it had a regulator in my version. That video I mentioned assured me that I did and how to adjust it. so I cranked it down a turn. It fired one shot then quit shooting. I freaked a little because I thought I recalled some controversy about adjusting a regulated gun with air in the reservoir, which is how I did it. The Spanish guy did his that way. Anyhow, I turned it back about a half turn and it started acting like it was regulated. I went up some more with it and adjusted the transfer port to make it smaller didn’t like that result so opened it back up. ( you have about 4 turns of the screw to work with and the first turn doesn’t do much) Then I adjusted the hammer preload. I have it the way I’m going to leave it, I think.

                    The regulator still isn’t working just right. The first shot after a refill goes off at a very low velocity then goes way up. It holds that for many shots, dips down for awhile then rises again until it drops off steeply. I’ll put up a graph that shows it better than I can explain it. I shot 2 separate strings with RWS Hobby just to make sure it wasn’t a fluke.

                    • Halfstep,

                      I’m thinking that the regulator just needs to be used a lot more before it becomes steady. B.B. I think experienced something like this in one of his recent reports using a regulated PPP (can’t quite recall which one though).


                    • Half,

                      Adjusting the regulator pressure down at least with the FX Crown with pressure will damage the regulator, adjusting up is ok. I would degas the gun and move the reg to the lowest setting and then move it up from there. Also as you move the reg pressure up you may come to the end of the adjustment where the screw will be released and fired out of the gun at pressure, just some stuff to think about. Do be careful.

                      Also you know about google translate; https://translate.google.com/ if you can scan the manual to text you can translate 5000 characters at a time, that could be useful.


                  • That was from a 220 Bar fill. That is the max pressure,by the way. If you or anyone else can explain whats going on, I like to hear from you. The review that Giles did on YT pointed out that his gun was just barely UK legal because when it got near the regulator setting the velocity went way up for a few shots and broke the 6 fpe law. He adjusted his hammer spring so that it never exceeded 6 fpe, but he also had to settle for a lower overall velocity for the entire string. So the reg ain’t great,so far, at least.

                    The sights are not fiber optic (yay) but the rear sight is only adjustable for windage. You loosen a screw and slide the sight in a grove left or right then lock it back down. My gun is shooting inline with the aimpoint but very high. The front sight is inserted into the barrel shroud (no silencing from this shroud)much the way a key is set into a motor’s shaft. It’s even rounded on the back end like a key. It’s held in place with a machine screw and looks as if it could be shimmed higher or the bottom could be filed to lower it, but that isn’t as adjustable as I would like. It has a long dovetail grove for an optic sight.

                    It’s loud, especially at over 12 fpe from a 8″ barrel. From watching other reviews I know that silencer adapters a available for it.

                    That’s the bad stuff, and now for the good. It has a good grip that fits my hand well. It has a good trigger that I think I can make even better. The fit and finish is very good. It gets lots of shots

                    Now for the accuracy.

                    I tested it the way I always do when possible, like the factory does, I clamp it in a vise. I know that doesn’t measure the shootability of the gun, but it tells me what pellets are accurate from it and that’s what I’m after, in the beginning. Her is a pic of some of the groups I got right off the bat. I’m shooting all of these at 13 yards and 1 inch from muzzle to target.

                  • I got very excited about the gun at this point because I had already found half a dozen pellets, cheap pellets for the most part, that shot under a dime at 13 yards. These next photos are from when I was charting the power curve of the gun. They are long strings that range from 35 to 75 shots.

                  • That’s a common adult aspirin next to it. I don’t have a trime to my name so I use aspirins. Here’s the rest of the groups. Tell me what you think. I know I now don’t care whether the reg is perfect or not. I wasn’t expecting anything like this from a gun with “Sport” in its name!!

                  • I shot 10 shot groups with 64 different pellets from 13 yards away with the gun vised.

                    Only 9 shot over 1″ groups. There were 4 pellets out of that 9 that put 9 shots in under 1″.

                    38 pellets printed under 3/4″ and 6 others put 9 in under 3/4″, some of them well under.

                    25 were 1/2″ or less and 8 more put 9 shots in 1/2′ or less.

                    17 WERE UNDER 3/8″. 4 more put nine in 3/8″ or less.

                    And I FOUND 9 PELLETS THAT WERE 1/4″ OR LESS ! ! ! with 2 additional ones that did 9 out of 10 in 1/4″ or less.

                    I plan to test at greater distance and I think, based on what I’m seeing here, that I will be buying or making a shoulder stock for this gun and using it as a carbine.


                    • Half,

                      That is great accuracy and a phenomenal number of shots from a pistole. A very good purchase. I bet the velocity stabilizes with more shots.

                    • Halfstep
                      Looks like a very nice shooting pistol. From the looks of those targets I bet it will shoot good out at 25 yards even.

                      And I believe that fps spike on the first shot is from the pressure still trying to balance. In other words the high pressure side keeps wanting to feed to the low pressure side. Maybe the longer the gun sets and not used the higher the first shot might spike too.

                      That would be easy enough to test. Just let the gun set for a few hours after a full fill and chrony it. And maybe it don’t have to be a full fill. But also if the high pressure side of the resivior has less air pressure then it might take longer for the low pressure side to build up more pressure.

                      I’m guessing the gun doesn’t have a pressure gauge on the low side does it. If it did you could watch the regulated pressure for each shot you take. That’s the way I have my Maximus set up that has the regulated bottle attached to the guns resivior now. If I watch the low pressure regulated gauge when I shoot you can see it spike down then come right back up.

                      But that’s what I think is happening.

              • GF1,

                I had to move up in the thread to leave this reply to ” Looks like a very nice shooting pistol….” because there was no room after your comment. I guess I messed up by posting that report so far down in the thread.

                Back to the gun. On the graph that I posted I’m confused by the way the velocity slowly goes down and then comes back up and then it does what you would expect when it goes off the reg, it falls off steeply. Others have said it may need to break in more and I hope that’s right. I’ve read here about plenum size, which I gather is the storage area after the reg, including the inside of the knock open valve, and how too small of a plenum can make the valve erratic. Do you know anything about that?


                • Halfstep
                  Yep the plenum volume definitely affects that.

                  I’m sure you seen the pictures of my Maximus that I now have the drop down adapter on to attach my regulated Air Venturi bottle on.

                  I purposely left the Maximus resivior long so it had plenty of the 1200 psi regulated pressure to feed the valve to the transfer port and barrel.

                  When I put the internal Huma regulator in my Maximus it acted just like what your exsperiancing with your pistol. And not putting the Huma regulator down. I liked it. But no way as much as I like my regulated bottle. Maybe that’s just the way the physics work with those internal regulators.

                  Maybe there even needs to be more volume on the high pressure side of the regulator to balance the low side better. Maybe that’s why bottle regulated guns are more stable from what I have seen.

                  • GF1,

                    I think for now I will just live with it. It sure ain’t hurting accuracy at 13 yards. I’ll try at 25 yds soon and if it doesn’t cause a lot of vertical stringing, I just won’t worry about it. I didn’t post the chart that shows the velocity for each of the 10 shots in each pellet’s test string, at 64 pellets it was 3 pages long, but for any 10 shots, the regulator keep the velocities very close. I was refilling after 50 shots, so that area is pretty stable.

                    I just can’t get over how unpicky it is on pellets. One of those aspirin sized groups was shot with those pointed Crosman pellets that come in a waxed milk carton. Incredible! I also failed to mention that all but one pellet variety entered the breech pretty loose. Not so loose that they would fall out, just real easy to load. Another thing I noticed when I was checking the barrel’s cleanliness with a bore light before I fired it, and it was clean, BTW, was the depth of the rifling. I have never seen such deep rifling in an air gun. I even check some other guns to make sure that I wasn’t mistaken. I don’t know if that’s why it’s accurate or not, but it’s not hurting the accuracy, that’s for certain.


                    • Half,

                      Interesting. Deep rifling and loose(ish) fitting pellets is quite the paradox. This also goes against the “smooth twist” method of FX. Is deeper better? 😉


                    • Halfstep
                      Yep on the accuracy so far. Very interested in what it will do out at 25 yards.

                      And to bad there isn’t a skeleton butt stock that will attach at the grips like the Crosman guns. I would probably be looking to get one if that option was available. Of course as long as it continues to be accurate out at farther distances.

                  • GF1,

                    They do make a folding skeleton stock just for this gun. I just haven’t found a source yet. I thought that a stock on such a short gun was silly, but I am rethinking that now.


                    • Halfstep
                      If you find that folding stock definitely let me know. That would make the pistol very interesting to me.

                      But I want to see your 25 yard groups when you get to it. And maybe even 50 yards.

            • Thanks, it shoots even better than in looks 😉
              This particular MK has been modded for a scope rail by Mac1, it is an LD.
              Its been further modified by a good friend of mine with a longer FX/LW barrel, brass accents, and custom furniture.
              Even better, it still retains its Crosman serial #001511
              Very early MK1

              • Erockrocket,

                I just discovered that one of mine has a 000328 serial number. Does that mean 328th one made? I posted some pics down below here. Weren’t you concerned about modding such an early gun? Did he mill a dovetail in the top?

                Do you know when yours was made? did you acquire it new?


                • Mac1 mills dovetails on the breech as part of his LD modifications.
                  Yes, I believe the 00xxxx numbered are the 1st gens, yours would be 328.
                  I bought my Mac1 LD used. I most likely would not have modded such an early pistol. I doo remember reading something about the early castings being a bit thicker in critical places than later gens, the earlier frames can therefore run at slightly higher PSI. I run mine at 850, and 1000 psi.
                  850 psi nets 11.2 fpe using 16gr AA, 1000 psi yeilds almost 15 fpe 🙂
                  The MKs are an excellent design, tuned up they really shine.
                  I chose to further mod this particular LD because I can’t leave nothing alone…..lol
                  A good mate in England had the brass bits crafted for me as a prezzy, the grips are by Vernon here in the USA.
                  The barrel was a spare from my bud in England, an old FX/LW barrel from a stash found at the old LW factory. It was a bit over 15″ prior to fitting to the LD, after was at 14.95″, just under the limit for pistol HFT class rules. I have a mastermachinist / good friend that did the fitment, stated it was his best work yet, the pistol is superbly accurate.

                  • Erockrocket,

                    It screams accurate. I haven’t really looked much into modded MKs so I don’t know whatLD means. I have heard of Mac 1, though I don’t really know what he offers. I guess I should look into it. What is HFT class, BTW?


                  • Erockrocket,

                    What do you mean when you say you run your gun at 850 – 1000 psi? My guns are still stock and they all run on CO2 at whatever pressure a cartridge is generating at the moment.

                    I guess I’m way out of touch 😉


                    • The MK pistols can also be used with HPA via an adapter made by Mac1
                      My pistol is setup for Hunter Field Target,
                      Do a google search for Mac1 LD

        • You have to put your thumbs behind the grip, and pull firmly on both knobs with your index fingers.
          It does work best if it is relatively low on gas.
          But does work if more full, but takes more effort.

      • 45Bravo,

        Sorry, I should not have started a reply from the previous report without the context. My Cousin had a pistol when we were kids mid 1960’s that I mistakenly thought was a Mark II. He somehow let a new CO2 cartridge excape in the bedroom when he was loading it. We were both very lucky to come out without a mark. The walls were not as lucky.

        The Pistol could not have been a Mark II as the cartridge cannot excape, even if the cap is somehow removed. It must have been a different pistol that looked the same.


  4. 49…………….474
    50…………….462 the liquid CO2 is gone

    Here’s a really dumb question for you:
    Did you say “the liquid CO2 is gone” because the velocity started to drop, and you know that’s an indication that you are working only on residual gas, or did you shake the gun to see if any liquid CO2 remained (can that even be done?)?
    *shrugs* As I said, a dumb question, but I just had to ask; thanks.
    Happy New Year to you,

      • “You can’t hear liquid under any circumstances.”

        Thanks, B.B., that’s a relief; my hearing’s not what it was; I was afraid you might have ninja-hearing skills that allowed you to hear that which I could not. =>

        “Yes, I said it was gone because of the large velocity drop.”

        Now that I took your advice and have a chronograph, I should actually start to research such things on my own. Thanks again.
        May the New Year be awesome for you,

        P.S. To any airgunner who does not yet have a chronograph you might want to do yourself a favor and get one of these:


        I love mine; it’s easy to use, and I’ve recorded velocities as low as 70 fps from multi-pump pneumatic pistols. I’ve got a classic slingshot pending from master wood worker, Hank (Vana2), and I think I’ll have to use the chrono on that, too…just for fun. =>

  5. BB
    So what was the power adjustment screw set to. Was it screwed in, out or someplace in between ?
    I am assuming you tested low and high power using the striker at the first and second stops.

    It’s a bit confusing having two different power adjustments. One a spring and the other a striker setting. How about if we call one way a full or half cocked striker and the other a variable power spring adjustment screw.
    Bob M

      • BB
        Why do you hate to mess with the spring tension adjustment.

        It should be no different than adjusting a Marauder spring tension.

        Just count your turns. Or is there something else that mak s you not want to mess with it?

          • BB,

            If your screw is set as it is in your Part 1 close up photo, then you have it all the way in ( highest power for both cocking positions). It will back out 3 1/2 turns and hit a positive stop and that, combined with the first cocking position, will be “low as she’ll go”.

            Your photo of the piercing mechanism looks as if there is a seal in there. If I’m correct on that, could that be another variation. In both of my Mark IIs the lip of the cartridge just butts against bare steel.

            My best friend’s girlfriend and later, wife, bought one of my guns new for him in 1972 when he was a HS senior. It has the pre ’75 serial number system that doesn’t indicate the build date, but I know its pedigree and therefore, how old it is. The second Mark II was gotten by another friend in a firearms trade and he just didn’t want it. I believe he gave it to me out of guilt because I let him steal a Colt ACE .22 from me a month earlier for $250 so I could buy my RWS model 52. I don’t know anymore than that about its history and the fact that your cap looks like it has a rubber seal in it made me want to date the gun. Someone has repainted it in the past and the serial number wasn’t stamped very deep and was filled with paint, making it hard to read, so I rubbed it a little and the paint chipped off. Since I had done the damage already, I scratched over the numbered area with my finger nail, only to discovery the 6 digit Pre ’75 number that wouldn’t normally help me date the gun. In this case though, I think it might. The number is 000328. Could that really mean that this gun is the 328th one made back in the sixties? At any rate, it doesn’t have a seal for the lip of the cartridge, which should eliminate any fear of taking a set if a cartridge is left in the gun.

            I’m going to post some photos of some of the paperwork that was in the 1972 box. It may help someone date their gun if it came with these ads and special offers.

            I see people here debating what Pellgun oil is so I also include some detailed pics of the older packaging on a tube of it. It claims a silicone base.


  6. BB
    So what was the power adjustment screw set to. Was it screwed in, out or someplace in between ?
    I am assuming you tested low and high power using the striker at the first and second stops.

    It’s a bit confusing having two different power adjustments. One a spring and the other a striker setting. How about if we call one way a full or half cocked striker and the other a variable power spring adjustment screw.
    Bob M

  7. As a matter of interest, the piercing cap used on the S&W 79g and 78g will work on the Crosman Mark I & II. I’ve been asked that question before and have done it on my Mark I. Someone on a forum asked the question because he had gotten a Crosman without the piercing cap and had a S&W pistol but had not tried to swap the piercing caps.

    Love all three of my S&Ws, but like the Crosman Mark I more and, for me, the Mark i is the most accurate. Now, if I just had a Mark II.

  8. Hey, don’t forget you can completely exhaust the CO2 by pulling the cocking knobs all the way to the rear! Then the cartridge is easy to remove. I didn’t see any comments about this…

  9. I shoot my Mk II on low power almost all the time. I did the same thing when I had a Mk 1. I also shoot my LD on low power. The guns seems just as accurate on low as on high power. Low power is much quieter than hi power if that matters to you. You can actually see the pellets sometimes. I used to have a bunch of plastic dinosaurs that I bought at a dollar store tethered to a fence all over my back yard. On low power I had enough power to knock the dinosaurs off the fence post without damaging them. Once they were all off the post I would reset them and do it again and again. It seems like I could shoot for ever on a single cartridge. For me it was a great way to relax and kept a grin on my face.

    To me the main benefit of low power is that it is much quieter and also that I get more shots per C02 cartridge.

    David Enoch

  10. There is a lot to like in these Mks I and II pistols, not the least the attention to detail in things like the trigger and sights, both fundamental for good shooting. I like the balance too, although I will admit that it is a personal preference. Regrettably, these are features that few new airguns in the medium-low end of the spectrum have.

    I am looking forward for the next report.

    To all, the very best wishes for a Happy New Year!


  11. Happy New Year!

    How many times have you seen knurled parts with those telltale crosshatch plier jaw marks at Airgun shows or yard sales!!!!


    “…large knurled cap…. Don’t use pliers to force it! Shoot the gun until the gas is gone or almost gone.”
    INSTEAD of pliers or those evil Vice Grips use a rubber strap wrench, a leather strap or soft jaw pliers/padded bench vice on any knurled fastener/cap…. Most of the time knurled parts SCREAM finger tighten ONLY!!!
    A puff of gas is a momentary loss; buggered knurling is there for a lifetime!

    END of RANT!

    finger tight shootski

    May you all be healthy, have enough to buy the airguns you “need” and shoot smaller groups than ever before!

    • Shootski, (off topic, other than for coffee drinkers)

      I did research coffee mills. Quite interesting as a specific grind warrants and specific type of brewing method (in general). Of course,…. me being me,….. this has led me to question the roast of the bean that I buy. Should I not roast my own (green) bean for the ultimate cup? What is the best roaster? Where do I buy green beans? What type? You see what you have done gone and started?,……… 😉

      For (now),…. I shall continue to “mutilate” my store bought roasted beans in my “whirly” grinder, overheat the beans and grind them to near dust. Of which,.. shall then be brewed in my sub $20 drip maker. You are far more of a Java connoisseur than me. I did get a couple of lottery tickets,…. so maybe I will be able to step up my coffee game in the near future? Not holding my breath on that though.Till then,… I shall continue to happily drink my “swill”. 😉

      Thank you for at least making me more aware of the topic.

      For anyone else,…. grinding your own roasted beans at home will (double the cup quality) that you now drink.

      Happy New Year to all. Best wishes, health and fortune,…… Chris

  12. Years ago I knew an airgun repairman in Portland, OR. Nice guy, he got me many classic airguns at good prices, including a Crosman 600. The one airgun he never found for me was the Mark 1. He told me of shooting a possum on his roof between the eyes with his Mark 1, killing it with one shot.

  13. To all of those out there in Airgun Land who are hesitating on getting a chronograph, don’t! These are great tools to have, even if you only have one airgun.

    Thedavemyster in his blurb up above attached a link for a very nice chrony that is not very expensive. I myself recently acquired a basic model Caldwell that works with an “app” that you can load on your so called smart phone or notepad. It allows you to collect, store and share all kinds of info in files. What are you guys waiting for?

    • RR
      Phones and apps. What happened to your flip phone?

      You got a smart phone now? Are you just using your iPad?

      See what I mean about smart phones. If you had one you wouldn’t need you iPad and you probably even take your phone with you when you go places. Why would you have a phone anyway. And then just think. You could even look up info on your phone app and post it on the blog while your not home. Just think how you could help other air gunners out wherever you are. They wouldn’t have to wait all the way till you got home to reply.

      And you started it remember. I was just reading your comment. 😉

      • GF1,

        LOL! No, I do not have one of those so called smart phones. I still use a flip phone and the only reason I have it is so Mrs. RidgeRunner can get in touch with me when she wants.

        No, that is not an iPad. It is a Kindle and I do not take it places with me, except maybe to the doctor so I can have something to read while waiting.

        I am truly sorry, but all the other airgunners are going to have to wait until I am home to be enlightened by my words of wisdom. 😉

    • B.B.,

      My apologies. The site did not even seem to be in the same league as P.A. from what they offer. I figured this one would be more than ok, given other links that are posted. I shall tread more cautiously in the future.


  14. BB/Tom,
    I’m glad you returned to this pistol. I bought a late model Mark I because of the 2005 blog and owning a Ruger target Mark I (bull barrel and target grips). I wish I had the time to shoot this wonderful pistol more frequently.

  15. B.B./Anyone,

    Where is Matt61???? I miss his insightful comments. I mean really,… what didn’t he know or had not researched very in-depth? Plus the full period dress shooting excursions. Anyone?


  16. BB
    I agree with Ridge Runner on that power adjustment screw. If it’s almost flush its on high power so don’t bother turning it if you haven’t done so already for me. It looks worn out already. Others may want to know the power change at the low spring setting.

    For the sake of curiosity I looked into the CO2 caps, both Mk I & Mk II for any CO2 cylinder seals. There are none.

    Once the cylinder is pierced all the CO2 liquid is free to escape into the sealed compartment that contains the cartridge. The only ‘o’ ring seals are in and on the screw in cap. One for the piercing pin and one on the cap housing tube forward of the threads. No compression seals are involved, just static pressure ‘O’ rings.

    Noticed something else too, the Mark I cap is has a two piece housing and the Mark II is a solid unit. The Mk I is held together with a snap ring under the piercing lever. The button type on the Mk II has a pressed in spring pin.

    Also the Mk I is threaded inside to receive a threaded cylinder that helps retain things on that end.
    The Mk II has a spring steel star washer wedged in instead of the threaded cylinder.

    I wonder if allowing the CO2 liquid to disburse into the grip housing helps reduce the cold created when CO2 gas is passed through the small pierced hole in the CO2 cylinder every shot when it is installed right side up like most airguns.
    I can send a parts breakdown pic of the Mk I CO2 cap if you like but I’m sure you already have it.
    Bob M

  17. Benji-Don,

    I hope the velocity stabilizes but as long as it’s shooting like this, I can live with the fluctuation. Will be a bigger issue as a carbine, I guess. I really feel like it is a bargain of a gun so far. Just realized that I don’t have any pics of the actual gun to post. Maybe tomorrow. Maybe PA will start importing it as an Seneca “something or other”. I bet it would sell.


  18. Mike in Atl,

    Had to start a new thread. I will check out Google Translate. I tried the app on my phone but it translates word for word. Doesn’t make a lot of sense with improper syntax and noun and verb placement. For instance the barrel is called the canon. I will be careful with the regulator until I can get some more complete instruction. So far this gun has been a real pleasant surprise for the money.


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