Logun’s Sweet 16 on CO2 – Part 3The other S-16s!

by B.B. Pelletier

Part 1
Part 2

Yesterday was a great day at the range, except for the wind. I tried to shoot groups at 50 yards with the S-16s, but the changing breezes blew my groups apart. The best I could do was 1.5″ for five Crosman Premiers.

Heavy trigger!
I have to say, the heavy trigger did affect how I shot. I found myself pulling the trigger with two fingers, which made the hold less steady. I do believe that a 3-lb. trigger-pull would improve the situation immensely.


A great day for range testing, but it was windy!

25 yards
So, I pulled the target in to 25 yards. With the strong breeze, that was the only way to complete this report. The 3-12x44mm Leapers scope scope was perfect for this application, and the ultra-high B-Square scope mount proved to be just high enough to bring the scope to my eye. Starting with Crosman Premier pellets that proved to be the best of the day, I shot several tight groups.

Shrouded in mystery
After my comment on the effect of the shroud, I tried it both on and off the gun. Wth the shroud on, the accuracy doesn’t degrade as much as I had thought it would at 25 yards – perhaps an extra quarter-inch larger is all with Crosman Premiers. At 50 yards, the shrouded groups were twice the size of the group shot without the shroud, so something is happening between 25 and 50 yards.


The best group at 25 yards was this group of five Premiers measuring, 0.252″.


The best group of JSB Exacts at 25 yards measures 0.456″.

JSB Exacts were also good, just not as good as Premiers. They also fell out of the magazine more readily until the mag was loaded into the rifle. I mentioned earlier that this was a problem with some pellets.

Not so good
A pellet I cannot recommend in this rifle is the Logun Penetrator. It simply refused to group better than one inch at 25 yards with the shroud off the barrel and nearly two inches with the shroud on.

Things to consider
This conversion to CO2 pushes the pellet several hundred feet per second slower than the rifle normally gets with air, so the pellets behave differently. When I test the rifle with air, I’ll probably use these pellets plus a few others. And another pellet might be more accurate under those conditions.

17 thoughts on “Logun’s Sweet 16 on CO2 – Part 3The other S-16s!

  1. B.B

    I’ mthe guy that bought the 392 that wouldn’t adjust. I traded it in for another gun. took it home and tried to adjust the elevation to bring it down an inch. and on the next shot it was 12 inchs high. The rear sight doesn’t have enough bend in it to keep it putting pressure on the adjustment screw. You can turn it all you want, there’s nothing that the screw can touch to get an adjustment on. It’s suspended in air! I shouldn’t have to take the hammer to a out of the box gun, should I?


  2. BB,

    Thanks for the recommendation to dave gunter but since i live in the philippines i cannot reach him. a philippine airgun website (geocities.com/heightaddict), advised that the valve spring be shortened to increase the power in an armscor .22 air rifle. is there any truth in this?

    Abel


  3. 392,

    Something is VERY fishy about this. I suspect that you have been buying damaged guns that some store is selling as new. I’ve never seen these kinds of problems with a 392.

    If I were you I’d take that rifle back to the store and get my money back.

    B.B.



  4. hi BB,

    I’ve been reading this blog for quite some time now (~3 months) and have enjoyed every article yet.
    my understanding of airguns has grown a lot.

    but now i was wondering, if you reinforce the hammer sping on a pump gun (a 392 or blue streak for example) and do more pumps, that would probably increase pellet velocity, i am not talking about PCP power, but increases of 15% to 20% in energy. would this be achievable without losing lots of durability?
    i think sheridan designed their guns with the best longetivity vs power vs accuracy ratios (like most quality airguns) but i was wondering how a small power increase would affect both the accuracy and durability of most multi pumps.

    i started this thinking because in a pcp, you look for the balance of air usage vs power.
    but in a multipump, it’s not a problem if you dump all the air at once since leftover air wil not be used anyway. so reinforcing the hammer spring makes sense to me, there must be a reason these guns are not widely modified with stronger spings to get more power ?

    please excuse me for my bad english, it’s not my natural tongue and i tend to mix up terms, thanks in advance for your patience

    krikke


  5. BB
    I can only guess that the drop in power from hpa to co2 is causing some of your problems but I have made groups at 50 yards with my gun using Premiers that could give you a run for the money on you 25 yard groups, also the shroud seems to have no effect on my gun as far as accuracy. Did i get lucky or did you get stiffed???

    By the way if anybody is interested here is a link
    http://www.airgunforum.net/agf/index.php?showtopic=10609&hl=

    A Russian fello made a custom trigger and tank set up but as far as I could find no such mods are avalabel for purchase.

    Still i love the gun, it shoots great.
    Thanks for all the info bb


  6. New topic — shooting better with iron sights.

    I was shooting a pretty consistent 540/600 with my air pistol before a hiatus of a month or so (coronary artery bypass — doing fine but avoid if at all possible). Somehow, I had apparently forgotten what was working well for me in the pause (plus, my upper body strength was nil but that is another topic).

    The “magic” that I finally rediscovered is to first align only the sights on the gun. I do this by aiming at a blank area of the target below the bullseye. I then shift my concentration to only the front sight and align the front sight with the bullseye ignoring what happens with the rear sights.

    I found that the fron sight gets “shorter” as it approaches the bulleye and if I try to get all three elements aligned simultaneously that I chase the alignment especially since the apparent height of the front sight changes as one nears the black bullseye. (Thus, approaching from below works better in my opinion.)

    My scores immediately jumped about 20 points with my second session after remembering this technique being a 543/600.

    I have read about shooting Garands with peep sights and that one should ignore the alignment of the rear sight (I am buying a M1 Garand so this was of interest for both reasons.) I suspect that the small size of the aperture and the tendency of one to overcorrect if trying to align all three elements more than compensates for any minor misalignment in the same way as I noted above.

    Hope this helps someone else move up to a new level of shooting.

    Joe


  7. Joe,

    I have a Garand and I sight the way you describe. I’m no whiz but I can still keep them aound three inches at 100 yards. You will love the Garand!

    I don’t recall ever shooting a 543 with an air pistol. I think my all-time high is 539, so you’re the man!

    B.B.


  8. S-16 owner,

    I think it’s a combincation of the day and the lower velocity with CO2. I did expect tighter groups at long range, but the wind took care of that.

    If you still have the heavy trigger, what do you do to compensate for it?

    B.B.


  9. Is shot an izh 46 the other day a liked it. I don’t have $300, so how does the daisy 747 compare with shootability and accuracy. Is there any others available. I currently shoot a walther cp (only pistol i have) and am looking for a 10 meter gun. I can keep 6 or 7 out of 8 shots in the black at 10 meters.

    Thanks,
    hb



  10. Hello B.B.;

    Though I have read your article on the Walther CP-88,(gives 1&1/8″ accuracy, looks realistic, 380 fps; I absorbed all that), I still have a question for you regarding this pistol. I would like to ask you for your impression of its trigger quality (which I don’t remember you commenting on in your write up on the gun). How hard is the pull? (single and DA), how much creep?; does it lose velocity when fired DA as opposed to SA?; finally; how fast will it shoot in double action mode (I know that a C02 gun will freeze up if too much of this is attempted, but I intend to use it for at-home target practice and my main cartridge pistols are both revolvers, a Ruger and a High Standard, so this is important to me). You may say that I should go with the Umarex Smith and Wesson 586 to simulate revolver shooting, but these Walther clones are really revolvers anyway. Besides, this is the only way I’ll ever own a gun that actually looks like a CP-88!

    Curtis


  11. hb,

    The 747 is a fine-shooting handgun. It’s a little nose heavy, but so is the 46.

    A nice compromise for you might be the Gamo Compact. It’s harder to pump, but lighter than either the 46 or the 747, and it has a trigger almost as nice as the 46.

    B.B.


  12. Curtis,

    The trigger isn’t as nice as the 586, but nothing else Umarex makes is.

    It will shoot as fast as you can pull the trigger. Unless you are Bob Munden, you won’t be able to get ahead of it. The double action pull will be considerably lighter than your Ruger (I have two Ruger revolvers).

    Single-action pull does have some creep, as do all Umarex pistols except the 586. But it is light, at 4 pounds or so.

    B.B.


  13. krikke,

    I am sorry I took so long to answer you. I forgot to answer on the day you asked the question.

    The valves in multi-pumps are balanced for the hammer weight and spring strength. They can be improved by a small amount sometimes by increasing the spring strength, like you suggest, but there will always be an upper limit.

    To get real gains from a multi-pump, the valve has to be redesigned.

    B.B.




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