Crosman 760 Pumpmaster Classic: Part 2

by Tom Gaylord
Writing as B.B. Pelletier

Crosman 760 Pumpmaster Classic
The new Crosman 760 Pumpmaster Classic.

Part 1

This report covers:

  • BB feeding
  • Loading pellets
  • Velocity
  • RWS Hobby
  • Velocity-per-number-of-pumps
  • Discussion
  • Sig Match Ballistic Alloy
  • Sig velocity-per-number-of-pumps
  • Crosman Premier Heavy
  • Premier velocity-per-number-of-pumps
  • Pump tube very warm!
  • Hobby pellets on 10 pumps second time
  • Hobbys on 10-pumps — again!
  • Crosman Black Widow BBs on 10 pumps
  • Trigger pull
  • Pump effort
  • Clacking pump handle
  • Summary

Okay — you are either for or against this airgun. There doesn’t seem to be much of a middle ground. I won’t take sides, but I am aware of all of your feelings.

BB feeding

First up is the “special” BB feeding method that I found quite by accident. I was reading the comments on the Pyramyd Air website and saw one or two complaints that the BBs don’t feed well in the new gun. With the older 760 I know they feed from the top inside of the receiver and you have to pull back the spring-loaded feed button on top of the receiver to get the BBs to fill that small magazine from the larger reservoir inside the receiver. My older 760 is a first model that holds 180 BBs. This new gun holds 1,000.

Once the BBs are inside the small inline magazine on top of the receiver they roll forward and drop one-by-one into the place where the bolt tip will catch them. When the bolt comes back they drop and attach to the magnet on the end of the bolt as if by magic. However, in my old gun they only feed correctly a fraction of the time. The new 760 Classic is different, in that the small BB magazine that feeds to the bolt is very visible. I showed it in Part 1. And I learned something that helps this new gun feed right every single time.

The BBs in the visible magazine on top, both old and new, roll forward when the muzzle is depressed. So when loading a BB (that’s cocking the bolt ALL the way back and easing it forward) you should see a BB on the tip of the bolt. The old gun has a brass bolt that has to depress a spring-loaded catch in order to rotate into its storage slot in the receiver after loading. The new gun’s bolt moves straight forward until the bolt handle pops up just a little as it closes at the very end of the stroke. With both guns hold the muzzle below level while doing this. That’s it!

Loading my old 760 is like playing with a magician’s trick box. I still haven’t learned the secret. Sometimes it works and other times I saw the lady in half! The new gun feeds BBs flawlessly.

Loading pellets

Pellets are a different story and no problem to load with either the new or the older gun, though the new gun has sloped sides to the breech trough while the older one has sides that are flat. The older gun has a screw hole in the center of the breech trough that is designed to turn half of your pellets around backwards as you insert them into the breech. The new gun has a smooth loading trough that works better, though it did flip around a significant percentage of pellets.

Velocity

Now let’s look at velocity. We have both pellets and BBs to test, so let’s get right to it. The Crosman box says the new gun gets up to 700 f.p.s. with pellets on 10 pumps, but Pyramyd Air lists it at a more conservative 600 f.p.s. with pellets. Why don’t we try that first?

Crosman 760 box
The box clearly says pellets go up to 700 f.p.s. on 10 pumps.

RWS Hobby

I’ll start with the RWS Hobby pellets pellet, since it is the velocity standard for lead pellets. On 10 pumps Hobbys averaged 578 f.p.s. However, something interesting happened as I shot the string. Let’s look.

Shot……Vel
1……….571
2……….573
3……….571
4……….569
5……….570
6……….574
7……….576
8……….584
9……….588
10………600

Up to shot number 5 things were very stable. But with shot 6 the velocity started increasing. I think we all know what’s happening. The pump cup or o-ring seal is warming up and sealing the compression tube better.

At the average velocity this pellet generates 5.19 foot-pounds of energy on 10 pumps. Since this is a pneumatic we expect heavier pellets to generate more energy and light ones to generate less.

I will come back to this with more interesting observances, but now I will do a different test — the velocity-per-number-of-pumps test.

Velocity-per-number-of-pumps

Pumps……Vel
3………….374
4………….414
5………….452
6………….495
7………….522
8………….551
9………….580
10…………599

Discussion

Okay, let’s talk. When I saw the velocity rising in the first string I figured the average velocity was really closer to the fastest velocity recorded than to the number I got. I will come back and test that in a bit.

Also, do you see how consistent this airgun is? I don’t think I need to shoot any more 10-pump strings. I will just shoot the number-of-pumps-per-shot tests on the rest of the pellets.

Sig Match Ballistic Alloy

If we are going for velocity we will get it with a lightweight pellet and the all-tin Sig Match Ballistic Alloy pellet is a perfect one to test.

Sig velocity-per-number-of-pumps

Pumps……Vel
3………….435
4………….481
5………….528
6………….559
7………….598
8………….630
9………….655
10…………676
Okay, I think we can take 655 as a conservative velocity average for this pellet on 10 pumps — see where I’m going with this? At that velocity this 5.25-grain tin pellet generates exactly 5 foot-pounds of energy at the muzzle. A lighter pellet has produced less muzzle energy — just as the theory suggests.

Crosman Premier Heavy

For a heavy pellet I chose the Crosman Premier Heavy. At 10.5-grains it fits the bill, plus it is a dome, and I wanted to test a dome in this airgun, too. Here we go.

Premier velocity-per-number-of-pumps

Pumps……Vel
3………….293
4………….323
5………….361
6………….389
7………….418
8………….439
9………….456
10…………469

If I take 456 as the average for 10 pumps (being conservative again), this heavyweight pellet generates 4.85 foot-pounds at the muzzle. Oh, oh. The theory failed! What happened? I don’t think it was the theory that failed as much as something else. Can you guess what it is? I’m about to reveal something that I think you will find interesting. So — why did heavier Premiers generate lower energy than Hobbys?

Pump tube very warm!

Before I show you what I think led to this result, let me shoot another string of Hobbys on 10 pumps per shot. And before I do that — remember what I said about the pump seals warming as I pumped? Well I felt the outside of the pump tube and at this point it was very warm. The seals are also definitely warm. Let’s shoot that string.

Hobby pellets on 10 pumps second time

Shot……Vel
1……….583
2……….584
3……….583
4……….586
5……….590
6……….585
7……….586
8……….577
9……….573
10………582

Now we have something to discuss! And THIS is a classic example of why a chronograph is so important! I told you earlier that I expected the average for Hobbys on 10 pumps to be close to the fastest velocity recorded. That would be around 600 f.p.s. Look what happened instead. On shot number 8 the velocity dropped below 580. What’s happening?

The answer to this question is the same one that I asked you just a little bit ago. Only at that time I asked why the heaviest pellet was not also the most powerful, as the theory predicts. I think the answer is oil — as in not enough of. I mean the pump seals are getting dry and that is shaving velocity off the top. So I will run another test.

Hobbys on 10-pumps — again!

This time I oiled the pump piston seal with Crosman Pellgunoil — (Crosman gun, so why not use their oil?). Then I shot 5 shots across the chronograph for record. Here they are.

Shot……Vel
1……….656
2……….645
3……….631
4……….616
5……….613

I didn’t bother calculating the average because the velocity was slipping so fast.

See what oil does? That is a dramatic result! But I knew the pump seals were warm, so I set the gun aside for two hours and then shot 5 more shots. This time the pump was cool and the oil had been spread around.

Shot……Vel
1……….602
2……….577
3……….579
4……….594
5……….581

This time I did calculate the average, which is 587 f.p.s. for these 5 shots. I think we can surmise that the average velocity with Hobby pellets on 10 pumps will be something above 580 f.p.s. but below 600 f.p.s. I could go on and do other interesting things, but how about a string of BBs? Since this is a Crosman airgun I will choose their BBs, but not the Copperheads that have always been on the slightly small side. I will use the new Crosman Black Widow BBs instead. The PA website says the gun gets up to 625 f.p.s. with BBs, while the box says 645 f.p.s. Remember I mentioned this in Part 1 and asked you why the pellets that are heavier went faster than the BBs? I think I now know the answer. Someone at Crosman overlooked this when proofing the artwork for the box, or something in the gun changed after that time and the box got out claiming 700 f.p.s. with pellets and 645 with BBs.

Crosman Black Widow BBs on 10 pumps

Black Widow BBs on 10 pumps
Shot……Vel
1……….603
2……….607
3……….612
4……….605
5……….607
6……….637
7……….616
8……….606
9……….607
10………600

The average for this string is 610 f.p.s. And, as you can see, BBs do go out of this gun as fast as 637 f.p.s. These Black Widows weigh 5.23 grains apiece, so the average muzzle energy calculates to 4.32 foot-pounds.

Trigger pull

The single-stage trigger pull is 6 lbs. 1 oz. I do note that the trigger became noticeably smoother in just the 65+ shots of this test. I think it will break in to be very smooth.

Pump effort

This gun is made for children, so the effort needed to pump is important.

Pumps……Effort lbs.
1………….18
2………….25
3………….27
4………….27
5………….28
6………….28
7………….26
8………….27
9………….29
10…………27

You have to decide what these results mean. Some kids won’t be able to pump the gun and others will. I will tell you that by pumping slow the effort stays as low as possible. You might loose a few f.p.s., but it shouldn’t be that bad.

Clacking pump handle

When the plastic pump handle smacks against the plastic frame of the gun there is loud clack. It’s louder than a loud hand clap and if you are pumping many strokes it does get distracting.

Summary

So far I find a lot to like about this new Crosman 760 Classic. At $35 it could very well be a best buy — as long as your accuracy expectations are realistic. We shall see.

27 thoughts on “Crosman 760 Pumpmaster Classic: Part 2

  1. B.B.,

    How much of the Crosman PelgunOil have you poured into this unit? Sounds like you’re going to need a tablespoon more.

    Siraniko

    PS Section Hobbys on 10-pumps — again!
    Fourth paragraph Third sentence: Since this is a Crosman airgun I will choose their BBs, but not the Copperheads that have alwatys (always) been on the slightly small side.


  2. BB,

    Like you said, this can be an inexpensive plinker for a kid. I remember in my youth my friend and I would hunt bullfrogs with his bb gun. I can see where a young’un could find a day of fun with something like this.



  3. Hi BB, another interesting article. There is something I would like to mention that I hope others will agree. I am not the strong, young man I use to be, so even though I like my Benjamin 392 and Benjamin 397, these Benjamin rifles are a major effort to pump, while the Crosman pump pistols and rifles like the Pumpmaster 760 are a lot easier to pump, so that I can have a longer shooting secession than with the Benjamin that tires me out quicker. If only they would either make a Pumpmaster 760 with a tighter bore barrel for bb only use and a true adjustable rear sight for windage and elevation, and a rifled barrel for pellet use only they would have a winner. I know, this is a price point/cost driven airgun aimed for the first time youth market, but to add just a little more in quality would appeal to a lot of older people like myself who just want a plinker for indoor or back yard recreation without too much effort.


    • The first 760’s were a rifled barrel.

      I say put the rifled barrel in it and if a kid wants to shoot bb’s in it so be it. I do understand what is meant by having one with a tighter smooth bore to help shoot bb’s more accurately. But I think a nice rifled barrel would do the trick.

      And just wondering has anyone tryed any lead round balls in thier smooth bore 760’s. Something like these. Maybe they just might be pretty accurate at a reasonable distance.
      https://www.pyramydair.com/s/p/Gamo_177_Cal_8_2_Grains_Round_Lead_Balls_250ct/78


      • Waldorf1, Gunfun1,
        I had an old 760 with the metal receiver and the wooden forearm and butt stock. It was a cool little backyard plinker (I eventually gave it to my friend’s son). I had the one with the smoothbore barrel, but I always wanted one of the fancy imitation brass receiver 761s with the rifled barrel:
        https://support.crosman.com/hc/en-us/articles/203543290-761XL-Owner-s-Manual-EVP-1972-1981-
        Besides the shiny receiver, they had an over-sized bolt handle.
        I guess they’re collectors items now. =>


        • Dave
          I have a I guess 760. That’s what I call it anyway. It looks like a 760. It’s all wood with a black metal receiver. No Tootsie roll pump handle and it has a rifled barrel. I got it in 1968.

          The gun sat in a closet in my later years. My brother bought some ground and built a house probably 25 years or so ago. He had some problems with mice and such when he got some chickens and such back then. I let him use the the gun since I was just letting it set around. He said he still has it. And he’s the type that don’t get rid of anything. So he still should have it. I’ll have to see. But I shot the heck out of that gun when I was a kid. It was always with me when us kids were out running around. I need to find out about it.


          • “But I shot the heck out of that gun when I was a kid…I need to find out about it.”
            Yep; I think you need to check up on that old gal; maybe post us a pic of her. =>


            • Dave
              I have meant to in the past but I forget to find out when me and my brother finally connect at his house. I’ll have to see if he can find it. Then the next thing is see if it still shoots. I found my old Benjamin pump pistol a while back and surprisingly it still pumped and shoots fine. And it hadn’t been shot for probably 2 decades. Anyway I will see if I can come up with the old 760 or whatever it is.


  4. Tom,

    I’ve been wanting to sign up and disagree with you for a while now… 😀

    I believe that the velocity increases you are seeing with multiple pumps are due almost entirely JUST to a warmer pump tube, not to less leakage from the piston. And with this gun, you got higher velocities after oiling because the oil made the pump chamber volume lower (a higher compression ratio) – just like adjusting a Daisy 717.

    You can prove this to yourself by heating up the pump chamber with a heat gun, and observing the results. Then let it cool over time, and do single-pump shots.

    Otherwise, I love your blog, and loved seeing you on TV (but am upset you aren’t featured more often!).



      • This will be my only disagreement. 😀

        I’ve finally got a proper pellet trap in the basement, and have been learning how best to shoot my 46m. It sat in the closet for many years.

        Thanks for your encouraging blogs!


      • BB

        I sort of agree with Izzy. That’s why I mentioned the issue of erratic velocity in single pump guns the other day. I think the testing that Izzy is proposing could be expanded to allowing the gun to cool between shots after the partial pumping technique. If the velocity goes down, it could be an indication of the air contracting as it cools, thus lowering pressure in the valve housing.

        You would, of course, have to start with a gun that you felt confident about retaining air in its valve, as leakage would skew the results. You could test the gun by pumping it slow and deliberate, fire it right away, then repeat the slow deliberate pumping and refrain from firing for a minute or two. If the velocities are close the gun is probably not leaking, over that interval, at least.

        Gosh, turning that over to you was much easier than when I thought about doing the experiment myself! :-)>

        Half



          • B.B.
            I’ll have to get on board with Izzy and Halfstep. I remember reading one of Robert Law’s pamphlets where he stated that springers were superior to single and multi pump guns (any contained air system) in achieving accuracy (all else being equal and at the time) because the pumped air was heated to a high degree and greater volume and then cooled down to a lesser volume over a short time. This is considering that varying velocities will give you a different POI.
            Larry from Algona


            • Larry,
              Adding a pressure gauge to a multi pump air gun would help the user pump to, and shoot at, a repeatable pressure, reducing the influence of the pump’s temperature on POI. Would that make it a PCP (like a Vectis)? – Don


              • Don,
                Ha Ha. I suppose so, but the price point would go sky high and these venerable guns would no longer be suitable for your entry level shooters.
                I only put this to say that way back in the late 70’s I was influenced to choose break barrels over the pumps – my aging mind went no further than that.
                LMo


  5. B.B.,

    Sometimes I am tempted to get the 760, but also the 2100B and the Daisy 880. I don’t know why, just to plink at blades of grass, I suppose.

    I was only now realizing that he Umarex Synergis doesn’t have the usual bear trap of the single shot rifles (yes, I would use the safe practices, regardless). Not that someone couldn’t get caught in it, but I think they would have to try.

    Lastly, the kinks have been worked out and I will purchase the .25 cal Marauder this Saturday. I overreached when I thought I would buy both that and the .177 from Jerry. I know I will shoot the .25 less than a .177, but I’ll just stick to the break barrel for that (for now). Even when I am not shooting, the .25 will look nice perched above the mantel.

    Wish you and your readers a Merry Christmas,
    ~ken




        • Ken
          Yep thanks. I seen on the recent blogs.

          Let us know what happens. You know favorite pellets and what distance your shooting at.

          I hope you like them. Oh and Merry Christmas to you too.


          • Gunfun1,

            I hope to do just that. I want to test things for myself. I already know the JSB Exact Heavy pellets are desirable. I will start at shorter distances. For grins, I will also test .177 pellets I have on hand; I want to see for myself. I already know that splatter targets are not the way to go for this; I need good paper targets. This will be different from my usual. Aside from spinner targets and knock down targets, I shoot targets stuck against a steel plate. I believe I need a better way.

            Anyway, thank you for your interest and feed back. This has been almost like getting something I wished for in the Sears catalog.

            ~ken


Leave a Reply