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BB’s new USFT rifle: Part 2

USFT
BB’s USFT rifle.

Part 1

This report covers:

  • First thing
  • Working pressure
  • Hand pump?
  • Labradar
  • Off to the races
  • First 10 shots
  • Shot 41 through 50
  • Shot 61 through 70
  • Shots 81 through 90
  • Where does it end?
  • There is more
  • What’s next?

Before we begin let me tell you that I am flying to Las Vegas this coming Sunday and I will be there until the following Friday evening, barring any problems. On Monday I hope to be out at Industry Day at the Range. I go to the show Tuesday through Thursday mornings and leave around 3 to write the next day’s report. It has to be published by 9 pm, Vegas time because that’s midnight on the east coast where the blog publishes. I don’t have a lot of time to answer questions, so I’ll count on you old-timers to cover for me.

Today we learn more about BB’s new/old USFT field target rifle. It didn’t come with a manual, but BB has some experience with this type of air rifle and that served him well with this new one.

First thing

Is the barrel really free-floated? Yes, it is. Those “barrel bands” that you see from the side don’t touch the barrel.

barrel band
Does this clear up the barrel band question?

Working pressure

This USFT is unregulated. It uses its valve to control velocity within the acceptable pressure limits. The problem is — BB didn’t know what those limits are. This is where a chronograph is invaluable. You really can’t proceed without one with this rifle. The “back-door-to-hickory-tree chronograph” just doesn’t work here. As you will see today, we are going to be extremely precise.

You may recall that the maximum working pressure is engraved on the receiver as 1800 psi. If not look at this.

USFT fill port and gauge
The maximum working pressure is engraved on the USFT receiver as 1800 psi.

That number doesn’t mean the rifle is to be filled to that pressure. It means not to fill above that number. But the reservoir gauge on the rifle has a green zone that lies between 1800 and 2200 psi. I think Mac1 bought the closest gauge he could find, or else there is another explanation that I don’t know. BB’s first USFT liked to be filled to 1650 psi, but not knowing anything about this one I filled it to 1800 psi on the gauge on my Air Venturi G6 hand pump, while the gauge on the rifle said 1800 psi. Yep, they agree. That’s rare, but I guess it happens. It’s kinda nice that it happened on this rifle, since we are soon going to split hairs — those of us who have them left to split.

hand pump gauge
At the end of pumping the hand pump gauge read 1800 psi…

USFT gauge
…while the USFT gauge said the same thing.

Hand pump?

BB, did you really fill this rifle with a hand pump? Yes, I did. Not that anyone who owns a USFT is ever likely to do the same but since the fill pressure is so low I thought it would be fun. Yeah — fun! Fun like splitting a cord of hardwood for the fireplace. That kind of fun. 

It took 300 pump strokes to fill the sewer-pipe reservoir from 1375 psi to 1800 psi. By allowing the pump to rest for five minutes as I pumped, it took 25 minutes to fill the rifle. It wasn’t hard but it was boring. When it came time to bleed the connection between the pump and the rifle very little air came out because, let’s face it — 1800 psi?

USFT gauge start
This is where the rifle’s gauge was when I started filling.

I then proceeded to shoot 144 shots before the rifle was certainly off the pressure curve. That’s a lot of shots! So many, in fact, that I took two days to shoot them. Today you will see the saga of how to determine the correct pressure curve for a precharged pneumatic (PCP).

Labradar

I learned in the process of shooting that the Labradar allows for a string of 100 shots before it opens a new file and starts over with shot 1. The first file isn’t lost, it just won’t accept any more data. I also learned that all this shooting over two day’s time (with the chronograph taken down and stored in between sessions) took the rechargeable battery down from 83 percent to 73 percent. It was the largest drop since I charged the battery once after receiving the Labradar.

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Off to the races

Since I know that USFTs like JSB pellets, I shot the JSB Exact Heavy that weighs 10.34 grains. Everything you see in today’s report was shot with that pellet.

Now just start shooting and recording the velocities. What else can you do? With my Air Arms Shamal I remember filling to 3,000, only to discover about 60 shots later that the rifle liked a 2600 psi fill. That’s a lot of shooting! The USFT took even more. Let’s see.

First 10 shots

Shot…….Vel.
1………….849
2………….841
3………….835
4………….845
5………….849
6………….845
7………….844
8………….837
9………….844
10………..848

Okay, you might look at this and think that the USFT will average about 845 f.p.s. But you would be wrong. Let’s skip ahead to shots 41 through 50 and see where that takes us.

Shot 41 through 50

Shot…….Vel.
41………..871
42………..867
43………..866
44………..872
45………..865
46………..870
47………..869
48………..872
49………..869
50………..873

Okay, this must be it — right? The rifle wants to average about 870 f.p.s. with this pellet. Oh, and by the way, the fill pressure at the start of this string was 1600 psi. But let’s advance to shots 61 through 70.

Shot 61 through 70

Shot…….Vel.
61………..879
62………..874
63………..879
64………..873
65………..874
66………..876
67………..873
68………..887
69………..876
70………..877

Here’s where you learn. If the previous string (shots 41 through 50) averaged about 870 f.p.s., this one looks to be maybe 7-8 f.p.s. faster. Have we arrived? Nope!

Look at shot 68. Oh, but BB, surely that’s an anomaly? No, it’s probably not; and don’t call me Shirley. When the velocity is increasing like this and there is a large leap forward, the rifle probably has more to give. 

How do I know? Experience over many years, and also experience with another USFT. The starting air pressure for this string was just 50 psi less than the 41- to 50-shot string, so 1550 psi. I don’t think we have reached the power curve yet. Yes, I have seen all the numbers so I do know what I’m talking about, but I promise you, that is what I thought at this point during the test. Been there; done that; got the t-shirt and wore it out.

I did think the rifle was getting closer to its optimal starting fill pressure, but I thought the average velocity for that curve might be up around 900 f.p.s., or so. So onward I went.

Shots 81 through 90

Shot…….Vel.
81………..891
82………..887
83………..890
84………..884
85………..886
86………..886
87………..885
88………..884
89………..885
90………..884

NOW we are getting into what I believed was/is the power curve for this rifle. The starting air pressure for this string was on the fat side of 1500 psi.

USFT gauge begin curve
Is this the start of the USFT number 92 power curve?

Where does it end?

From shot number 91 to shot number 118 the lowest velocity was 881 f.p.s. The highest was 902 f.p.s. That’s a 21 f.p.s. spread over 37 shots. 

Shot 119 went out at 814 f.p.s. That was an anomaly because shot 120, the very next shot, went out at 894 f.p.s. From shot 120 to shot 123 the high was 898 and the low was shot 123 that went out at 891 f.p.s.

Shot 124 went out at 868 f.p.s. That’s an anomaly for sure because at 5 feet from the chronograph the shot was moving 870 f.p.s. Remember — the Labradar records velocities at 5 separate distances from the muzzle. That’s faster than at the start, which is impossible for a ballistic projectile. Something must have been off in the chronograph triggering circuit on that shot.

Shot 137 went out at 886 f.p.s. and shot 138 was 874 f.p.s. If we call shot 137 the final shot in the power curve, that’s a total of 56 shots with a velocity spread of 21 f.p.s.

After shot 137 the number started becoming inconsistent. Shots 138 to 144 started out from a high of 900 f.p.s. to a low of 872. The total velocity spread if we add that string to the one we are looking at becomes 30 f.p.s. over a total of 63 shots. Most competitors wouldn’t accept such a large spread, but a duffer like me might find it okay.

There is more

Yes, there is more. What I didn’t tell you is this string didn’t start at shot 81. That was simply shown for the sake of convenience. Shot 78 went out at 882 f.p.s., so we could add another three shots on the starting end, giving us a total of 59 shots if we stay at a 21 f.p.s. spread or 66 shots if we go for a 30 f.p.s. spread. And we aren’t done yet.

What we need to do now is fill the rifle to the fat side of 1500 psi and run another string. Oh, BB, does this testing ever end?

It does end. We are simply refining what we now know about this rifle. Would I ever fill to 1800 psi again? Not a chance. It’s  waste of air and time because I have to shoot the rifle 77 times before the velocity climbs up to the power curve.

What’s next?

Next is a fill to the fat side of 1500 psi and a plan to shoot around 60 more shots to pin down the power curve for this rifle. Are you confused? When I strip away all the early shots from 1800 psi things should clear up a lot.

After that comes accuracy. We gonna have us some fun!

57 thoughts on “BB’s new USFT rifle: Part 2”

  1. BB: using the Hill hand pump, how do you filter the moisture that’s compressed in the air. Is there some sort of inline filter? I wouldn’t want that beautiful rifle to rust. Orv.

    • Orv,

      With a hand pump, most of the time the water will condense inside the pump and gathers in a small chamber in the bottom of the pump. This is where the pressure release valve is. When you relieve the pressure, it blows out.

      As for that filter with all the moisture beads on the Hill pump, it does nothing as far as moisture is concerned. It does make a good particulate filter though. I guess if you were really, really anal about changing out the beads and keeping the ambient air away from them when not in use, it may help, but…

      • RidgeRunner,

        Call me Anal, but filling with the dry air delivered by a Dive Shop cascade fill system helps ensure fill to fill consistency of the shot air charge density.

        Anal accuracy nut territory ahead!
        Just think with a break barrel, single or multi pump airgun there is NO way to control the charge air density!

        shootski

        • shootski,

          How do they control the density? The surrounding air pressure and density changes constantly. It is true that they have better filtration systems which remove all particulates AND moisture. I have added extra filtration to my airgun compressor which removes even more particulates and moisture than it did before. I have a fine appreciation for anality, but sometimes it is a little overboard.

          Now, do not get me wrong. Please do not change your ways. What is right for you is right for you. When I went big bore, I bought a compressor, a large CF tank and extra filtration to eliminate any particulates and moisture that may enter through the compressor. I was mostly concerned with moisture as I live in a high humidity area. Some may call me anal also.

    • It’s worth noting that while the water condenses in the pump as RidgeRunner says, extended pumping without bleeding off the air will cause the water to accumulate to such a degree that it can work its way up the hose and into the tank (by my observations). For this reason, I always bleed the pump at least every other five-minute pumping session, and I keep the rifle elevated slightly above the pump’s chamber so that the moisture tends to run back to the pump.

      Daniel

        • B.B.,

          Sorry for that! ;^) Funny how moisture in the reservoir always ensures a higher blog reply count.
          For everyone’s information high relative humidity in the air charge results in lower density air in all airguns. When the reservoir/valve of a PCP or pump up gun contains liquid water it is at 100% Relative Humidity. During the shot cycle as pressure drops Adiabatic cooling causes even more water to condense out of the air charge and you might get a cloud out of your muzzle. The more water, up to the maximum of 4% by weight, results in a lower air density of the shot charge and a certain amount (smallish) loss of power.

          My originally reply to RidgeRunner was mostly tongue-in-cheek knowing he would rise to the occasion.

          For Danial and everyone else worried about water in the valve/reservoir because of all the corrosion horror stories perpetrated by the Forums it isn’t the problem they think it is! The real problem is mostly contamination with salts and body oils during assembly or fiddling (repairs) that are to blame. Sometimes manufacturers are to blame for using dissimilar metals that cause galvanic corrosion.
          A drop or two of a NON petroleum based oil (Chamber Oil) on rare occasion will help avoid any corrosion and even stop most of the contaminant and galvanic corrosion; it should certainly make you feel better :^)
          As B.B. and Dennis Quackenbush’s testing points out the water is expelled as liquid or vapor during the shot cycles.

          shootski

      • Daniel,

        All good practices. I have never had to worry about that much moisture, but I do like to have my air rifle higher than the pump base when I am hand pumping.

        I have to admit that now that I am becoming a senior citizen (read old geezer), I use my compressor and carbon fiber tank more often than my hand pump, but with some of the more recent gals that have found their way here to RRHFWA, I find I am more inclined to fill them with the Hill.

        What has been really nice is to get away from those high filling pressures. That is one reason I like this air rifle that BB is reviewing. It proves you do not need 4500 PSI to get decent power, range. accuracy and shot count. The Girardoni was a war weapon. It would hurl about 20 huge lead balls with an 800 PSI fill. Then you changed the butt reservoir and keep on fighting.

  2. B.B.
    Since you are going to do all the work anyway, why don’t you write the owner’s manual for this rifle?
    Both LD and Timmy Mac are still around to help.
    You often criticise written manuals and now is your chance to show how it should be done!
    Enjoy LV!

    -Yogi

      • B.B.,

        I’m still laughing as I write this!
        I can’t imagine the typical buyer of one of these needing or even wanting an Owner’s Manual ;^)
        Don’t even try would be my most respectful advice.

        shootski

        PS: I think Yogi has been around LD once too often…it is rubbing off.

    • Yogi,

      I am afraid that I have to agree with shootski on this one. Anyone who needs an owner’s manual for this air rifle has no business owning one. Besides, they are really pretty simple to operate and maintain. They are just of a higher quality than most airgunners are used to.

  3. BB,

    The velocity spread wonders me a bit. I think if you will start in the working point at 1500psi and go 50 shots the spread will not be so big. There is a pressure regulator in it, right?

  4. BB,

    This reminds me of when I shot for the power curve of my first Talon SS with the long Weihrauch .177 barrel (Mac’s). Shooting H&N Silver Streaks, I started at 3000 PSI with 400 FPS. I do not recall how many shots it took to reach the top of the power curve (quite a few), but once I got there, I was cooking along at over 1100 FPS at a little under 1900 PSI according to on my hand pump gauge. I used to fill to the fat side of 1900 PSI and get over 20 shots before it dropped off the top of the power curve. It would spit out the humongous Eun Jin 16 grain pellets at over 800 FPS.

    Are you listening Gunfun1?

    • RR
      Yep I hear you. That Talon SS has a 12 inch .22 caliber barrel in it now. It still likes a 1800 psi fill pressure.

      I also have a .25 caliber Condor SS with the factory 18 inch barrel that shoots 35 grain pellets a few digits under 1000 fps. It is the happiest at 2000 psi down to 1000 psi and gets many shots and is very accurate out in the 100 yard plus range.

      Yep I like the low fill pressure pcp’s too. 🙂

  5. Way off topic but interesting. Just got the MP7 brake barrel pellet airgun and removed the big block fake silencer. It actually adds 5″ to the barrel length. Wanted to see how hard it would be to brake it open and cock it. Almost impossible with only the 4 inches of exposed barrel but I did it. Then I had to shoot it so I dropped in a pellet opened the back door and fired it off into the pitch-black night and to my surprise about a 3/4″ inch flame shot out of the barrel. Freaked me out for a second, “What the …? before I realized I should have cleaned the barrel out first. Never actually noticed that in the daylight.

    • The flame was from the copious amounts of oil inside the cylinder from manufacture. Both this and the Uzi suffer from the same problem and even after hundreds of shots they still diesel.

      • Hope the piston seals can take it. Need to check out the FPS while it’s still running hot. May have an MP7 firearm for a bit. You would never see it with the fake silencer on.
        Think I’ll look for a long 1/2 28 flash hider to replace it. 🙂

  6. >>> Would I ever fill to 1800 psi again? Not a chance. It’s waste of air and time because I have to shoot the rifle 77 times before the velocity climbs up to the power curve. <<<

    BB,

    It may be blasphemous to even think about add a regulator because >> 59 shots if we stay at a 21 f.p.s. spread or 66 shots if we go for a 30 f.p.s. spread <<< is not "bad".

    I just can't help but think that, regulated (if possible), it could have been over 150 shots with less than half the spread. Still, 66 shots from a 1500 psi fill is good.

    REQUEST PLEASE…
    If JSB is at the SHOT show and you are talking to them, could you ask if they would consider making the .22 caliber Monster Redesigns (25 grain pellets) in a HADES configuration. There are many PCPs that have the power but not the correct rifling twist to shoot the heavier slugs. A 25 grain, .22 caliber HADES would give the market an expanding (hunting) projectile at power levels close to that of many .25 caliber airguns.

    Wishing you a good trip to the SHOT show BB, be safe and have fun!
    Hank

  7. B.B.,

    “I think Mac1 bought the closest gauge he could find, or else there is another explanation that I don’t know.”

    The 3K engraved on the USFT’s reservoir’s Burst Disk in the First Thing photograph is telling in my opinion.
    With the OPTIONAL double regulator build you could probably fill to the 2k+/- psi (green arc on reservoir gage) and shoot an entire Match and still need to degass to fly home!

    But both of us are making assumptions since we don’t have the owners manual, LOL!
    I would call Tim and ask him if I owned one; he does have the correct answer.
    I’m certain of that!

    shootski

    PS: Your next shot string after you fill to the fat side of 1500 is going to tell us what this rifles regulators, if it had the Ninja and Huma regulators, should be set to.

  8. B.B. and Readership (especially in France and the UK) listen up!

    “In the UK and France, birdlife that wouldn’t normally be prone to bird flu, such as barn owls and kestrels, have recently been infected. “The theory,” Smith says, “is that lots of big poultry operations have rodents, and the rodents aren’t necessarily dying of bird flu (H5n1) but are carrying the virus on their fur, then those barn owls and kestrels are catching them.”
    This is also causing chicken egg prices to soar around the World and Broiler Chickens won’t be far behind!
    So airgunners of the World it is time to step up! Get out there to the poultry farms and volunteer to KILL oodles of rats and mice!

    shootski

    • Ok shootski, I’ll take your bait:

      I, who am in France, will not kill any rodents. After all, I will have invited them with animal feed and shelter.
      Should another rat or mouse place itself in one of the waiting traps, then I shall relocate it too, a few kilometres down the road. That’s my choice. 🙂

      I understand that it is somewhat of a taboo to admit to the pleasure of hunting, despite it being natural for predators, and that all sorts of excuses get dreamt up to sell the sport (sport = activity that pleases), but bird flu, really?! 🙂

      • Triple HI
        I would have to imagine you are a pretty busy relocater then if that’s how you do it.

        I seen and still see what happens at farms if you don’t control them. It gets bad fast.

        No disrespect but you actually relocate them instead of eliminating them?

        Oh and huh, what do you mean bird flu? Yes bird flu.

      • hihihi,

        “…but bird flu, really?!”
        Yes i’m serious! H5n1 appeared in China some decades back and by 2021 was killing millions of wild birds as well as causing farmers around the world to cull brooding birds by the millions on farms around the world. Just recently Japan began plans to kill (cull) 53,000,000 chickens! All it takes is one infected bird and it in turn infects about 100 others. H5n1 doesn’t just make the birds feel terrible for a week or two; it is virtually always FATAL for most bird species including many of the raptors. Rats and Mice are suspected of carrying the VIRUS on their fur and spreading from farm to farm as well as to raptors that catch them. So you shouldn’t “relocate”. rodents you may be inadvertently spreading diseases to othe farms.
        So this isn’t a sporting undertaking hihihi. This is VECTOR elimination for the good of animals and the public.
        The more animals that are infected the greater the chance of a mutation that allows a jump to other animal species (yes even horses) and even to humans.

        shootski

        • Shootski,

          I know of 2 farmers that use cats for the most part to take out the rats and mice, they do not know if cats can carry the virus or not but they also use airguns and 22.lr to take out the others and then dispose of the critters thru fire or just putting them in a deep hole in the ground. Yes it is important to just stop the spread however you can.

          Mike

          • Mike in Atl,

            We had a Tom that always brought his fresh kills to my wife. I told her I was getting jealous.
            That takes some number of dedicated mousers to keep the rodents at bay on a farm!
            The farmers I have helped with a bb gun have always been amazed at how quiet, how many, and NO damage done with an airgun. I have had a few ask how much cash or product i wanted since they never expected a guy with a bb gun to be effective at elimination. I always turn them down. My latest was at a garden supply store i shop at shooting city rats and mice in the seed aisles they are much less bothered by lights and people. I’m talking with a bakery owner i know about his supply building problem that may take using aloy pellets since he is concerned the Health Department would go nuts if they found a lead pellet. He can’t believe I won’t shoot if there is a chance of a miss. But I can’t blame him for being worried.

            shootski

    • Shootski
      With you.

      I bet one of those big .50 caliber projectiles might just knock off 2 rats in one shot .especially if they swarm over the top of each other like I have seen at different times.

      My Wingshot double barrel I got a little while back is a really good rat and mouse killer. My brother has my Wingshot 2 and he uses it all the time around the chicken coop.

      We done some night shooting a bit ago at his house, him with the Wingshot 2 and me with the Wingshot double barrel. He put out a old square battery powered lantern think it was. All we did was sit around and wait for the glowing eyes to appear and start swarming around. Then blam, blam and blam. About a hour later and the rats were now out eating the dead ones. Crazy stuff. Guess they are hungry. Probably too many and only so much food supply. My brother’s chickens.

      • Gunfun1,

        I would be very hesitant to shoot the DAQ .58 ShortRifle at a bunch of rats near a chicken coop! It might knock down the coop after going through 40 or 50;rats! Even the .58 Outlaw pistol might take out 15-20 and still knock down the coop at shorter ranges. Lol!
        I think the DAQ .410 Camp and Garden Shot Pistol loaded with #8 will keep the coop and chickens safe while dispatching the rats and mice quickly at 20 to 30 feet.
        You and your Brother’s Wingshots must be very effective on the vermin for sure. Most folks don’t realize how much damage and illness the rodents do on farms. I don’t know how they don’t see the rats in downtown Washington DC…maybe because there are so many they just think the rats are the Blacktop.

        Good shooting,
        shootski

        • Shootski
          The Wingshot 2 and Wingshot double are very effective with 6 or 8 shot at about 20 to 25 yards. If there are 3 or 4 together at that distance it’s definitely lights out for them.

          And you know how that night of shooting came about. My brother and his daughters was feeding the chicken and guess what happens one of the rats ran up his pant leg to his knee then turned around and ran right back down just as fast. He said that was the straw that broke the camel’s back. And luckily his dauggters didn’t see it. If thet did it might of ended them helping him after that. Well maybe. Both of his daughters are tom boys too like my daughters. But I don’t know if I would of liked that either.

          Anyway have fun with your guns. 🙂

  9. BB
    Please stop reporting on these guns that Gunfun1 wants but will probably never be able to get. 😉
    Can’t wait for the accuracy report though.

    Will be waiting for some Shot Show updates. Have fun if you can. 🙂

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