Posts Tagged ‘Hill handpump’
by Tom Gaylord, a.k.a. B.B. Pelletier
We’re back to the BSA Scorpion 1200 SE. When we last tested it, we looked at the velocity and discovered this is a 30 foot-pound air rifle. So, its primary purpose is hunting. I thought that meant I should test some heavy .22-caliber pellets, but I also included a middleweight.
This test was done at 50 yards. I never shot the Scorpion indoors at 25 yards because it’s so loud. I went straight from mounting a scope to shooting at 50 yards. As it turned out, that cost me several more shots than normal to get on paper.
I scoped the rifle with the UTG 6-24X56 AP scope with illuminated reticle.
I knew the scope would be right for the Scorpion because BSA PCPs are very accurate. I wanted a lot of power in the scope to compliment the long-range capability. This scope gave me what I was looking for.
The first pellet I tried was the 21-grain Beeman Kodiak. The first group wasn’t good because the wind kicked up just as I fired a couple of the shots. Sure enough, the 10 holes had a horizontal spread. They measure 1.006 inches between centers, which isn’t bad, but I felt this pellet deserved a second chance.
The second group of 10 Kodiaks measures 0.926 inches between centers. Although that isn’t that much smaller than the first group, this group is rounder; and I feel it’s representative of what Kodiaks will do in this rifle.
Eun Jin dome
I said during the velocity testing that the 28.4-grain Eun Jin dome would probably be good if you were seeking the maximum knockdown power at long range. They developed an additional foot-pound of muzzle energy. They’ve never been the most accurate pellets, but in some PCP rifles they do deliver credible accuracy.
Not in the Scorpion 1200 SE, though. The Eun Jin gave a large groups with a pronounced vertical spread. It measures 1.488 inches between centers and was the largest group of the test. I don’t recommend this pellet in the Scorpion 1200 SE.
JSB Exact Jumbo Heavy, 18.1 grains
Next, I tried the JSB Exact Jumbo Heavy domed pellet. This one is between the medium-weight JSB Jumbo and the heavier Beeman Kodiak, so it gives better velocity with some good power retention. If it shoots at least as well as the Kodiak, it would be worth choosing.
But it doesn’t just shoot better — it shoots WAY better than the Kodiak in the Scorpion 1200 SE. Ten pellets made a group that measures 0.792 inches between centers. The group is very round, as you can see, so we know this pellet is a keeper!
JSB Exact Jumbo 15.9 grains
The last pellet I tried was the 15.9-grain JSB Exact Jumbo. Sometimes this pellet is the best in a PCP rifle, so it had to be tried. This time, however, was not one of those times. Ten pellets made a 1.332-inch group that was not as tight as the Kodiaks or the 18.1-grain Exact Jumbo Heavys. And no wind caused the horizontal spread of these pellets.
The BSA Scorpion 1200 SE certainly has the power and accuracy needed to be a good hunting rifle. I like the way the stock balances in my hands when shooting, as it’s heavy at the muzzle. I don’t care for the fact that it needs 232 bar of fill pressure because that drains even a carbon fiber tank quicker than a 200 bar fill. It does, however, get a reasonable number of powerful shots per fill (25).
The 10-shot magazine is flawlessly reliable. There was never a misfeed in the entire test. And the magazine is below the top of the receiver, so it never interferes with the scope. The trigger is light enough, but I don’t care for the stage 2 creep that I found impossible to adjust out.
I would recommend this rifle to all who like its looks and features.
by Tom Gaylord, a.k.a. B.B. Pelletier
We’re back to the BSA Scorpion 1200 SE. My hand has finally healed, and I can now work the Hill hand pump, but I stopped part of the way through the first fill and made the necessary changes to the carbon fiber tank hose, to attach BSA’s proprietary fill probe. I gave up because I just got tired of pumping! Those who encouraged me to do this from the beginning have won me over, I guess.
This PCP rifle takes a fill to 232 bar, which is 3,365 psi. We’ve looked at fill pressures for pneumatics a lot over the past month, and today we’ll see what this BSA rifle manages to do with its fill. The advertised number of shots is 25 per fill.
Because of the power potential of this rifle, I switched my backstop to the tough one blog reader Jim Contos made for me. If you want to read about this fine homemade quiet pellet trap that’s strong enough to stop the most powerful smallbore air rifle, here’s the link.
Familiarization with the magazine
After 10 minutes of trying (and failing) to load the 10-round spring-loaded magazine, I was prepared to blast BSA for creating a magazine that’s impossible to load. What we had, instead, was a B.B. who refused to learn new ways. The magazine loads easily once you do it the right way! I took a photo of the correct hold, so you won’t have the problems I did. Hold it like this and realize that BSA has designed this mag so the last pellet loaded holds the spring-tensioned drum in place until you’re ready to load the next pellet, and everything will be fine.
The magazine accepted all 3 of the pellets used in this test without a problem. They’re among the heaviest and longest .22-caliber pellets on the market, so I think you’ll be satisfied no matter what you try to shoot.
Pellet 1 — JSB Exact Heavy and the shot count
The 18.1-grain JSB Exact Jumbo Heavy pellet averaged 883 f.p.s. in the rifle. The velocity ranged from 875 to 888 f.p.s. over 25 shots. And 25 shots proved to be the limit, exactly as advertised. After shot 25, the next 5 pellets went this fast.
Clearly, the rifle has just fallen off the power curve but in slow motion. So there are actually 30 safe shots on a fill, and that equates to 3 full magazines. I’m so glad BSA publishes accurate figures for these things, as many other airgun companies seem to have no clue what’s right!
At the average velocity, this pellet produced 31.34 foot-pounds of muzzle energy. And I bet this pellet is also accurate, though that has to wait until I get out to the range, because this rifle is too loud for shooting inside the house. I took a risk by chronographing it for today’s report, but that’s as far as I’m willing to go.
Pellet 2 — H&N Baracuda
The second pellet I tested was the 21.3-grain H&N Baracuda Match. These are longer pellets that sometimes have difficulty feeding through rotary magazines like the BSA’s, but there was no problem today! They averaged 815 f.p.s. and ranged from 811 to 819 f.p.s. At the average velocity, they produced 31.42 foot-pounds of energy at the muzzle.
The Baracuda is another pellet that should prove very accurate in this rifle. They should be the best pellet at 50 yards, but that remains to be seen.
Pellet 3 — Eun Jin
The third and final pellet I tested was the 28.4-grain Eun Jin dome. This is a very long pellet and may be the longest that will work safely in the BSA magazine. But they did fit perfectly and had no hangups once I learned how to load the magazine correctly.
Eun Jins averaged 718 f.p.s in the test rifle. They ranged from a low of 713 to a high of 726 f.p.s. At the average velocity, they produced 32.52 foot-pounds of energy at the muzzle. In other rifles, these pellets have never been the most accurate at 50 yards, but they have often been accurate enough to use as hunting pellets. However, as close as H&N Baracudas are in power, I would choose the most accurate of the 2 pellets after we test them at distance.
The velocity remained very tight throughout the entire fill with all 3 pellets that were tested. That means BSA has balanced their valve to work with exactly the amount of air they recommend using. And the fact that they got exactly the number of powerful shots they advertised was a welcome bit of news. Also, 25 shots is a good number for a rifle in this power class.
Adjusting the trigger
I mentioned in the first report that I would be adjusting the trigger in this report. To do that, the action is removed from the stock. The sear is a direct-contact type, so care must be exercised to not get the engagement surfaces too small, or the trigger will be in danger of jumping off from a bump.
The owner’s manual is a single sheet of paper printed on both sides, but the instructions for adjusting the trigger are good and thorough.
The screw on the left adjusts the trigger-pull weight of the second stage. The nut and screw in the center adjusts the sear contact area and then locks in place. That adjustment affects the length of the second-stage pull. The screw under the trigger blade on the right adjusts the first stage and should not be touched, according to the manual.
I adjusted the trigger as light as it would go and set the sear as close as it would go and still be safe. The trigger still has significant creep in stage two, but it’s light and breaks at 2 lbs., 4 oz. I can work with it set this way.
50 yards next
Because of the rifle’s power, I’m going to skip the 25-yard test and go straight to 50 yards. If I’m successful, we should see accuracy that will override shooting at 25 yards, anyway. If I discover that’s the wrong way to do the test, I’ll change at the range and shoot at 25 yards first.
by Tom Gaylord, a.k.a. B.B. Pelletier
It’s taken me awhile to get back to this pistol because I injured my hand, so I couldn’t fill the Hatsan AT P1 PCP air pistol from the hand pump for a couple of weeks, but last Friday I was at it again — probably for the last time. You may remember that I discovered that the AT P1 likes a fill pressure of 3,200 psi — which is sort of ironic in light of several recent reports I’ve done. This time, I used the Hill pump to fill the gun to that pressure to see if there are 10 good shots on a fill. That was the problem before — the circular clip holds 10 pellets, but the gun didn’t seem to want to shoot more than 7 of them on a single fill of air.
I decided that instead of wasting time with a lot of different pellets, I would concentrate on the one good pellet that I knew gave the best accuracy. That’s the Beeman Kodiak. First, I filled the gun to 3,200 psi, then loaded the clip and inserted it into the gun. Someone asked me how I held the gun to shoot it, given that it’s scoped with a Leapers UTG 3-9X40 AO rifle scope. The eyepiece has to be held within 2-3 inches of the eye in order to see the image. There’s a way to hold the gun that uses the scope as one of the handles, and that’s what I did. I photographed it for you, so you can see it as I describe the hold.
I hold the back of the scope at the eyepiece and let my hand separate the rear of the scope from my sighting eye by the required distance. My hand is pressed against my safety glasses to maintain the separation. The weight of the pistol rests directly on the bag, so all my other hand does is keep the pistol steady. With this hold, I can squeeze the trigger without moving the gun.
This hold is one I learned while shooting the LD Mark I pistol from Tim McMurray. That’s a Crosman Mark I Target pistol that Tim converts to add a longer bafrrel, a CO2 tank hanging down from the grip and a rifle scope mounted on top — just like this one. With the LD, I rested the external tank on my chest and held the scope like you see here. That gave me near-rifle accuracy.
The result is a steady hold — especially when you consider I’m shooting only 25 yards. I don’t recommend holding a recoiling firearm pistol this way, but you can get away with it on a PCP.
All targets were shot at 25 yards. The first target looked very good until the final shot. I could see that the pistol was grouping low and to the left, but all I was interested in was the size of the group. It could always be moved later with a simple scope adjustment. The group that formed looked very encouraging until the last shot, as I said. I could clearly see that one go high and into the center of the bull, ironically enough. But when I walked downrange to examine the target more closely, it wasn’t as good as it had seemed. A line of four shots appears to the right of the main group, and they’re strung vertically up to the center of the bull. The last one is the highest one. I never saw the other 3 shots in the string, so they could have been any of the preceding 9 shots. All I could see through the scope was the large group that formed at 7 o’clock on the edge of the bull.
I guess this first target took the wind from my sails. It was no better than any of the previous targets shot with this pistol. My idea that a higher fill pressure would keep 10 shots in a tighter group was bogus. But I still had time on the range, so I thought something else was in order. I adjusted the scope higher and to the right just a little, to correct for where the Beeman Kodiaks had grouped. Then, I loaded the gun with 10 JSB Exact Monster pellets. The Monster pellet weighs 25.4 grains, making it even heavier than the .22-caliber Beeman Kodiak. And it’s a JSB. I wondered if this might be the pellet that turns things around for the AT-P1 pistol.
Alas, it wasn’t. It turned things around, all right, but not for the better. The pellets were all over the place! In the end, 10 of them printed a group measuring 1.933 inches at 25 yards. It’s more of a full-choke shotgun pattern than a group shot from a rifled barrel!
Now, I was really downhearted. I switched back to the Kodiaks and give them one final try. The gun was, again, filled to 3,200 psi, and 10 more pellets went downrange. This time, the results were not as good as the first time. Ten pellets made a group that measured 1.211 inches between centers. It was higher on the target and also centered better, which proves my earlier statement that the group can always be moved by adjusting the scope, but things were not getting better.
Outcome and final evaluation
I put a lot of time and energy into testing the Hatsan AT-P1 pistol. The reward was not worth the effort, in my opinion. While I agree that Hatsan does know how to make a fine precharged air rifle, the AT-P1 pistol is not as refined as the rifles they make. It’s too large and too coarse for what it delivers. I wanted it to succeed because there aren’t that many nice PCP pistols to choose from, but the test results do not live up to the hope.
I think that if you’re interested in an airgun like thi,s you should look at the AT-P2 pistol, which comes with a shoulder stock. That way, you won’t have to learn how to hold the gun like I did here. As long as you know how few shots you’re going to get on a fill of air (7) — and you manage that, you’ll be fine.
by Tom Gaylord, a.k.a. B.B. Pelletier
This test is being done because in Part 3, the accuracy test, I felt the scope I was using wasn’t giving the Hatsan AT P1 PCP air pistol the best chance for success. It was a vintage Weaver K856, which means a fixed 8x magnification with a 56mm objective lens. Though it doesn’t say anywhere on the scope, I’m pretty sure the scope’s parallax is fixed at 100 yards. At the 25 yards I was shooting, the target was slightly blurry.
The best group I got in that test was five Crosman Premiers into 0.678 inches at 25 yards. That was shooting off a sandbag rest with a rifle scope.
I said at the end of that report that I would return with a different scope mounted and try again, and today is a report on how that went. The scope I selected this time was the UTG 3-9X40 AO True Hunter that hasn’t hit the market yet. It’s a full-sized rifle scope with a suggested retail price of $104.97, so I would expect to see it sell for something less than that. I’m not going to report on this scope in detail today, but you do need to know that it’s a fine scope for this test. The parallax adjustment worked perfectly, and I was able to get the target bulls into sharp focus. The way I had to hold the pistol to use the scope was a detractor, but it’s no reflection on the quality of the scope, itself. I plan to do a full report on just the scope, but I’ll mount it on one of my rifles of known accuracy.
As I reported, the Hatsan pistol has a proprietary quick-disconnect fill probe that isn’t compatible with other airguns outside the Hatsan line, so I attached it to the hose on my Hill pump. I need my carbon fiber tank for filling all my other PCPs that are universally compatible with the Foster-type quick-disconnect fittings, so the Hill was dedicated to this pistol. It took 26 pump strokes to fill the pistol after 10 shots were fired. That’s 2.6 pump strokes per shot. I said in the last report that the gun seems to give the best results with 7 shots per fill; but since the clip holds 10 pellets, I shot it 10 times per fill. All of today’s groups are 10-shot groups at 25 yards. I feel that’s only reasonable because nobody wants to stop shooting and fill their gun in the middle of a clip.
Shooting was off a sandbag rest, which is fine for a PCP. This pistol does recoil a little when it fires, but that’s well after the pellet has left the muzzle of the gun. The recoil is more of a rocket-like push than a typical firearm recoil, and it’s far from the violent jump of most spring guns.
I overfilled the pistol the first time. I couldn’t clearly see the gauge on the pump and wound up putting 3,500 psi into the gun, rather than 3,000. So, just this one time, I shot 20 rounds on a fill instead of just 10. Had my groups been great, I would have gone back to the chronograph and looked at the velocity again with a 3,500 psi fill.
The Hill pump is great because it allows for such a fill. Other hand pumps peak at 3,000, but the Hill keeps right on going to 3,500. I bought it from Compasseco (which is now owned by Pyramyd Air) years ago when I was testing several BSA and BSA-made derivative PCPs because they’re all pressurized to 3,350 psi.
JSB Exact Jumbo Heavys
The first group fired was 10 JSB Exact 18.1-grain Jumbo Heavy domes. The scope was not sighted in, and the group landed about 4 inches below the aim point and 2 inches to the right. It measures 0.844 inches between centers. While that’s not much better than good, it beats all but 1 of the groups I made with the gun the last time at the range. Since this was 10 shots and not 5 or 7, I have to say that I did measurably better with the new scope.
Since the built-in pressure gauge said there was still about 180 bar left in the pistol after the first group, I loaded the clip with another 10 JSB Jumbo Heavys and shot again. Before shooting, I adjusted the scope through rough guesswork and managed to hit the lower right quarter of the bull at which I was aiming. I really like how well the new UTG scope adjusts, and I like how the knobs can be locked after every adjustment.
This is significant. It means there are more than the 7 shots per fill that I reported in Part 3. But I had to overfill the gun to get the other shots. More on that thought at the end of the report.
Please note that the largest of these 2 groups was 1.053 inches for 10 shots. In the previous test, the 10-shot group fired with the lighter JSB Exact 15.9-grain Jumbos was 2.093 inches. This one is a good four-tenths of an inch smaller. I think that is good evidence that the scope is the big difference this time; and if there’s a secondary difference, it’s that I am learning to shoot this pistol. However, I didn’t shoot this 18.1-grain JSB before, so my comparison isn’t perfect.
The trigger-pull was extremely long and mushy as the pistol came from the box, and it does not help the groups one bit. It’s hard to hold steady when pulling through a long, heavy trigger-pull. Also, I have to hold the end of the scope with my left hand to keep the spacing for my eye so I can see through it. If I were to try to freehand it, I would never be able to see through the scope because the image would keep blacking out with small movements of my eye and hand. So, the hold is both difficult and uncomfortable. A pistol scope would be better, though I doubt the groups would get any smaller with one.
The trigger is adjustable, however, and this is one of those rare instances in which the adjustments really work! I adjusted the long pull in my office after the range and got the trigger breaking fairly crisp and quite a bit lighter. This might have helped the groups by some amount.
I’ve tried adjusting this Quattro trigger in some Hatsan spring rifles before and didn’t see as much improvement; but, of course, in a PCP the trigger isn’t holding such a heavy spring.
Next, I filled the pistol to 3,000 psi and loaded 10 Beeman Kodiaks. This time I thought I had it right until the two final shots. Shots 9 and 10 went high and right from the main group. Eight shots went into 0.701 inches, but the last 2 shots opened the group to 1.118 inches.
This group sort of reminded me that 10 shots were too much for the AT P1 pistol on a 3,000 psi fill, even at 25 yards. Eight seemed to be the maximum with the new UTG scope. But there was one more pellet to try.
I took Skenco New Boy Seniors along, but they’re too long for the Hatsan’s clip. They protrude and don’t allow the clip to turn when the gun is cocked. The only other pellet I had to try was the Crosman Premier.
Once more, I got 8 shots in a smaller group that measured 0.791 inches, then shots 9 and 10 went wide and opened it to 1.266 inches. One went to the left and the other went right, as though I was throwing curve balls. I couldn’t see the pellets in flight; but when I saw the hole each one made, it came as a surprise.
Ten Crosman Premiers went into 1.266 inches at 25 yards from a rest. The first 8 shots went into 0.701 inches, and shots 9 and 10 went wide right and wide left. Once again, 8 shots were relatively close with 2 fliers.
Based on all this data, I’m going to say there are only 8 good shots per fill in this pistol with a 3,000 psi fill. Given the results of both days on the range, I believe I can safely make that statement. But since I was able to fill the pistol to greater pressure and get additional good shots, I think it might respond well to a fill pressure of 3,200 psi and be able to shoot all 10 shots.
The Beeman Kodiaks and Crosman Premiers seem to be the best 2 pellets in this pistol. Next time, I might try a third pellet that hasn’t been tried…like the JSB Exact RS.
Not done yet
I’m not yet finished with the Hatsan AT P1 pistol. In the next test, which I think will be the final one, I’ll try filling to 3,200 psi to see if I can get 10 good shots on one fill. If that doesn’t work, I’ll go back to the 3,000 psi fill and only shoot 8 shots per group. Now that I have a good scope, 2 good pellets, a knowledge of the power curve and fill pressure limits, plus a newly adjusted trigger, I think I can make the gun perform at its best.
Why am I willing to do all this testing? Because there aren’t that many good PCP air pistols available, and I think this might be a good one once I learn all its secrets. I owe you readers that much because so many of you are considering this one.
by Tom Gaylord, a.k.a. B.B. Pelletier
Today, we’ll look at the performance of the Hatsan AT P1 PCP air pistol for accuracy at 25 yards. It took a long time between this test and the last one because this gun is too loud to discharge inside the house. I had to do it for the velocity test and my ears are still ringing. I waited for a day at the range to test the gun for accuracy.
I mounted a vintage Weaver K-856 scope on the gun for this test. It’s a fixed 8x scope with a 56mm objective lens. I thought it would be clear enough at 25 yards (parallax set for 100 yards), but it turned out to be fuzzy. I will change scopes for the next test.
Before I left the house, I filled the gun to 3,000 psi with the Hill pump. You may remember that this pistol has a proprietary Hatsan fill probe, and I wanted to install it on something I could leave it on for a while. My carbon fiber tank is too busy with other guns, so I dedicated the Hill for this job. Because the AT P1 has such a small reservoir, I felt it would be okay to fill the pistol this way. This is the problem with proprietary fill couplings — they have to be installed on something, making it impossible to use that fill device for your other pneumatic guns that have universal Foster fittings.
After filling the gun, I looked at the Hatsan tank gauge. It read about 50 bar, even though I had just put in 206 bar. I knew it was full, so I left it alone. The next morning, the gauge needle was up to 100 bar, but it never did read correctly. That caused a problem at the range when I shot the gun down too far. It was then that I learned that the gauge needle bears no relation to how much air is in the tank.
I started out shooting a group of 5 Crosman Premiers. The first shot landed a quarter-inch below the next 4. The total group size was 0.678 inches, but 4 of those shots went into 0.322 inches. As it turned out, that was the best group of the day.
The trigger-pull was both too long and too heavy for the best in precision. I can normally work around almost anything, but this time the trigger-pull was a real hinderance to good shooting.
I shot the next 5 Premiers at a fresh target after adjusting the scope down. This time, 5 shots went into 0.993 inches, which is considerably larger than the first group. It alerted me to the fact that there may not be 10 good shots on a charge of air.
The pressure gauge on the gun now reads about 180 bar, so I thought there were another 10 good shots in the gun. It wasn’t until later that I discovered the gauge doesn’t read the pressure correctly.
The next 10 shots were JSB Exact 15.9-grain Jumbos. They landed in a group measuring 2.093 inches between centers. That certainly isn’t a good group — especially for just 25 yards. This group has too many shots and was shot with too little air pressure in the tank, but even then the shots are so scattered that I doubt it’s the right pellet for this pistol. But because I don’t know that for sure, I’ll try this pellet again in the next test.
I filled the tank again and changed to Beeman Kodiaks. This time, 10 pellets went into a group measuring 1.464 inches. The last shot went far to the left of the main group. Because it landed in the white, I was able to see it hit the paper. That was the tip-off that 10 shots were too many — even at only 25 yards.
I’d wanted to shoot 10-shot groups, but the AT P1 doesn’t seem to have enough air for 10 good shots on a single charge. According to the chronograph testing I did on Part 2, it has air for about 7 shots, so I limited the next groups to that.
The learning curve this day was too steep for me to be satisfied with these results. I’d lost my edge toward the end of the session, and it wasn’t worth pushing on. I’ll return for a second try at 25 yards with different pellets. And I’ll give those JSB Jumbos a second chance. If I can’t do a lot better than this, I won’t bother trying to shoot the pistol at 50 yards.
The trigger-pull on the AT P1 pistol is too long and heavy for the best accuracy. Also, the scope needs to be changed to give the pistol its best chance to do well. Hopefully, I’ll be able to find another good pellet next time and these problems will disappear. As powerful as this air pistol is, it’ll make a good hunting airgun if it can hit what it shoots at.
by Tom Gaylord, a.k.a. B.B. Pelletier
Today, I was all set to report the velocity of the .22-caliber Hatsan AT P1 PCP air pistol, when I discovered that there’s more I need to know about this airgun. I’d like to thank those who’ve been waiting patiently for this second report. I stalled for a long time because Hatsan uses a proprietary quick-fill probe. That means I have to undo one of my more universal fill connectors to attach their probe. Thankfully, the threads on their probe are standard 1/8″ BSPP that connect to most air hoses coming from tanks and hand pumps these days (I can still remember when that wasn’t true!), but I was working on both the Condor SS and the twist-rate report and needed a fill device for both of those. In the end, I pressed my Hill pump into service, and it proved to be a great way to fill the AT P1 pistol.
The first problem I encountered was with the 10-shot rotary clip — but I want to stress that it wasn’t the pistol’s fault. It was mine. I tried loading 28.4-grain Eun Jin domes that looked like they fit the clip well, but proved to be too long and jammed the gun.
Because they were the first pellet I tried, I thought the gun might be broken until it dawned on me that the pellets were the problem. Once I changed to Crosman Premiers, the gun functioned perfectly and there were no more cocking or feeding problems.
Rotary clips are sensitive to the length of pellets. If they stick out on either side of the clip, that can cause the gun to jam, as this Hatsan did. So, when selecting pellets for a rotary clip, keep this in mind. I chose the Eun Jin pellet for the weight. I thought it would allow this powerful pistol to develop its maximum power, but I went too far.
Removable air reservoir
In Part 1, I completely neglected to mention this pistol has a removable air reservoir. I saw the degassing tool in the tool kit and knew that it could only be used on the other (hidden) end of the reservoir, but for some reason I didn’t think to mention it.
Of course, the reason for a removable tank is so you can carry extra charged tanks in the field. Each one will give you more shots. I don’t think this is such a great feature after you learn how many shots you can get on a fill, but the choice is yours. At least Hatsan gives you the option.
Shots per fill
This will be the remainder of the report because I discovered during velocity testing that the AT P1 pistol has a very specific power curve. It’s not an inverted bathtub curve — where the velocity rises to the optimum level and remains there for a number of shots before falling back down again. Instead, the velocity rises, peaks and drops instantly. The curve looks like a peaked mountain with no flat spot at the top.
The manual says to fill to 3,000 psi and that there are 35 useful shots per fill. Several readers expressed doubts that the 50cc reservoir held enough air to give 35 powerful shots, and I agreed with them. If this was a target pistol, then 35 shots would be very possible; but at the power Hatsan claims, which is a .22-caliber pellet traveling 780 f.p.s. at the muzzle, it seems impossible to get 35 good shots on so little air. And, indeed, it isn’t.
My first fill was higher than 3,000 psi, and the velocity was depressed for many shots. When it did rise, it did so in a straight up and straight down fashion. There was no group of shots going at similar velocities. This told me I needed to control the fill very carefully.
I also noticed that the pistol fell off the power curve with about 1,800 psi remaining in the reservoir. But I didn’t stop shooting there. I stopped with about 1,500 psi remaining in the reservoir. From this test, I was able to determine that the pistol used about 62.5 psi per shot. I did that with a chronograph and with an accurate pressure gauge on the hand pump. The pressure gauge that’s built into the test pistol’s reservoir reads several hundred psi too low to be of much use.
I know how much air is in the reservoir when I start shooting because that’s what the pump’s gauge reads when I stop filling. I know how much air is in the reservoir when I stop shooting because that’s the spot on the gauge where the reservoir inlet valve is overcome by pressure during the next fill — you can see this when the gauge needle clicks at the opening of the inlet valve.
It took 1.5 pump strokes per shot, so refilling the reservoir went very quick. That’s why I believe the Hill pump is the best way to go, and the possibility of spare reservoirs isn’t worth the effort.
The shot count test
The next test I conducted began with a fill to exactly 3,000 psi on the hand pump’s pressure gauge. I used Crosman Premier pellets, exclusively for this test. I’ll give you the velocity readings and then interpret them afterward.
I’m not going to give you an average for this string because I don’t know which shots you want to consider as the good shots. Clearly, the pistol was slower at 3,000 psi on the hand pump gauge. And, remember, this is with the more accurate hand-pump gauge. The pistol’s built-in gauge was still showing about 2,700 psi at this point. Either way, there’s too much air pressure in the gun because the valve isn’t opening as long as it should, as evidenced by lower velocities.
Let’s say I like 761 f.p.s. for the first shot. If you agree, then the first 5 shots in this string were wasted. At 62.5 psi per shot, the gun was overfilled by 312.5 psi when it was filled to 3,000 psi. Since these gauges don’t read that accurately, let’s round that back to 300 psi overfill and say I need to stop filling the reservoir when the pressure gauge reads 2,700 psi.
If you select a different velocity as the start point of the shot string, then the beginning fill pressure will need to be adjusted accordingly. This is why I am not giving you an average velocity today. I can give average velocities, but before I do you need to know what is behind my numbers, because this pistol operates within narrow limits.
If I take the second reading of 761 f.p.s. as the ending shot in the string, there are a total of 7 good shots in the string. I think that’s probably too restrictive, and I need to expand my velocity variation allowance. If I allow a velocity variation of 74 f.p.s. between the fastest and slowest shots in the string, I can get 16 good shots on a fill and can start the fill at exactly 3,000 psi.
Do you see how I’m doing that? I’m using the chronograph numbers and accepting all shots until the pistol no longer drives Crosman Premiers out the muzzle at a velocity of greater than 700 f.p.s. My choices are arbitrary; but until I make them, I can say nothing about the shot count of this pistol
Well, maybe that’s not entirely true. Whatever I select as the acceptable velocity variation, I can say with certainty that this air pistol can never get 35 useful shots on a single fill. Where I draw the line is my choice, of course. If I want to shoot groups at 50 yards, the variation has to be tighter than if I want to hunt with the pistol out to 30 yards. Do you see how the anticipated use of the gun drives the useful number of shots you’re going to get?
When you change the clip, the gun must be cocked to pull the loading probe back out of the clip. Then, the clip’s axle must also be withdrawn to the front of the gun and held out of the way. That’s a separate brass bolt on the right side of the gun. The clips come out and go back in easily enough when these things are done.
Here you see the bolt probe that pushes the pellet into the barrel (brass pin in the clip recess) and the brass clip axle (the head is a brass knob) that’s been withdrawn to the front of the gun to remove the clip.
This gun is LOUD! I had to wear electronic ear protectors when testing it in my office. And although my office door was closed, my wife, Edith, remarked on the loud discharge when I was finished.
In the next report, I’ll test the pistol with several good pellets and give you some of the velocity data you’re used to seeing. But when I do, you’ll know what’s behind my numbers.