Posts Tagged ‘air pistol’
Pellet velocity versus accuracy test: Part 4
by B.B. Pelletier
Today we lower the velocity of the Whiscombe and test each of the four pellets, in preparation for the next accuracy test.
One reason I selected the Whiscombe for this series of tests is the fact that I can control the power output over a wide range of velocities by installing various transfer port limiters. For those who are new to airgunning, every spring-piston airgun like the Whiscombe generates a brief blast of compressed air by means of a piston racing forward in a compression tube. In the Whiscombe’s case it is actually two pistons racing towards each other. At the exact end of their travel a small air tunnel called an air transfer port conducts the compressed air from the compression chamber to the base of the pellet, where it blows it out the bore.
The amount of compressed air is extremely small, but the pressure is fantastically high for a brief moment — as much as over 1,000 psi. In fact, well over 1,000 psi. Now you probably also know that precharged airguns operate on compressed air that is at an even higher pressure, but the difference is, when a precharged valve opens, it does so relatively slow, releasing air at far below the pressure that’s in the reservoir. But a spring piston gun doesn’t have any valves, so when the air is compressed, it flows through the air transfer port to the back of the pellet like a small explosion. Everything the gun has to give is right there at the same time.
However, if anything gets in the way of this air as it flows, it slows down the flow and the resultant energy output of the gun. The amount of compressed air remains the same, but the rate at which it flows is slower, and the pellet is not moved with the same sudden push.
That’s a fancy explanation for the Whiscombe’s air transfer port limiters, which are nothing more than Allen screws that screw into the threaded transfer port. In the center of each are holes of various sizes though which the air must then pass.
The rifle has a threaded air transfer port. It’s shown here without any limiters installed.
These limiters have various sized holes that reduce the airflow through the transfer port when they are installed. For this test I will install the largest one on the left.
The transfer port limiter is installed with an Allen wrench.
Velocities
Now let’s see what changes have been made by the insertion of the transfer port limiter. I will shoot the same four pellets as before and in the same order.
Beeman Devastator
First I tested the Beeman Devastator pellet. This is the pellet that gave an average velocity of 1,205 f.p.s. in Part 1 without any transfer port limiter. With the limiter I show being installed above the Devastator’s average velocity dropped to 1,123 f.p.s. In the first test the spread was 28 f.p.s. In this test is was 16 f.p.s., running from 1,116 to 1,132 f.p.s. That isn’t a huge drop in speed, but the power that was 23.32 foot-pounds in the first test has dropped to 19.89 foot-pounds. We will see what this does to the accuracy.
Premier lite
Next came the Crosman Premier lite pellet. In the first test they were averaging 1.134 f.p.s. for an energy of 22.56 foot-pounds. The spread in that test was only 12 f.p.s. In this test the same pellet averaged 1,057 f.p.s. for an energy of 19.56 foot-pounds. The spread was an even tighter 6 f.p.s., running from 1,054 to 1,060 f.p.s. That is incredible performance at this power level.
Beeman Kodiak
Beeman Kodiaks came next and they averaged 992 f.p.s. in the first test. That generated an average 22.29 foot pounds of energy at the muzzle. The spread in test one was 22 foot-seconds. After the transfer port limiter was installed the average velocity dropped to 937 f.p.s. for an energy of 19.89 foot-pounds. The total velocity spread was 24 f.p.s. — ranging from 927 to 951 f.p.s.
Eun Jin
The heavy 16.1-grain Eun Jin was the final pellet I tested. In the first test they traveled 726 f.p.s. and generated 18.85 foot-pounds of energy. The spread was 13 f.p.s. With the transfer port limiter installed they averaged 687 f.p.s. for an energy of 16.88 foot-pounds. The spread with the limiter installed was 10 f.p.s. — from 682 to 692 f.p.s.
What’s next?
Next I shoot groups at 25 yards with each of these pellets so we can compare them to the groups fired with no transfer port limiter. That will give us our first look at how velocity affects accuracy.
After that I install another limiter that restricts the airflow even more, so the rifle shoots slower. And then we shoot it at that level for accuracy.
At the end of this test I still have one pellet out of four that’s supersonic. The Devastator, at 1.123 f.p.s. will always be supersonic where I live. The Crosman Premier, however, will be right on the cusp of the sound barrier and whether of not it breaks though will depend on the day.
Tomorrow
Normally I would run the accuracy part of this report immediately after the velocity report, but something wonderful happened at the range on Wednesday. So I am making a special report on Friday to show you something very amazing — at least in my eyes. And no, it isn’t the Ballard. Not yet.
Smith & Wesson M&P 45 air pistol: Part 3
by B.B. Pelletier
Smith & Wesson M&P air pistol is highly realistic. It shoots both pellets and BBs.
Today is the day we answer the long-awaited question of how accurate the Smith & Wesson M&P 45 air pistol really is. Is it capable of shooting out a one-inch bullseye at 23-24 yards, as one owner claimed, or does it conform to what we know about this level of air pistol?
Two different types of ammo
For starters, this pistol shoots both BBs and pellets. Usually when a gun does that, it has to give something away for the compromise, because BBs are much smaller than pellets. They are also made of steel and cannot take the rifling; so when you shoot a BB, you have to shoot it as a smoothbore. I tried them first.
BBs — not that hot
As expected, eight BBs did okay at 25 FEET. Nothing spectacular, but eight shots did land in a group that measures 1.747 inchs across the two widest centers. That’s minute-of-pop-can accuracy, but nothing more. I shot Daisy zinc-plated BBs for this.
I did discover during this session that the sights needed a lot of horizontal adjustment. The group of BBs at 25 feet was slightly low and three inches to the left. I loosened a locking screw on the rear sight and slid it to the right to correct this, and it took two corrections to get it right. When the shots were centered on the bull the rear sight was noticeably over to the right.
Now, on to pellets
I had suspected that it wouldn’t be BBs that were so accurate, but lead pellets. So I was all set for a surprise when I shot them. The distance to the target was 25 FEET from a supported standing rest. I shot single-action and I can report that my eyesight has returned to about where it was in the past.
I shot many different types of pellets, but two stood out enough to be worthy of mention. The first were H&N Finale Match Pistol pellets. They shot to the point of aim and grouped well, though there was always one or more that opened up the group.
I actually shot several groups of this pellet, because they were teasing me with groups that were almost perfect, but never quite. Finally I came to the conclusion that we are seeing the best the pistol can do with the two groups I’ve selected to show.
Eight H&N Finale Match Pistol pellets made this 25-foot group, which measures 0.936 inches.
Another eight H&N Finale Match Pistol pellets made this 0.955-inch group. It’s very close to the other group and also to the groups not shown.
The other pellet that really did well were JSB Exact RS domes. I tried them because they are lightweight and very accurate in lower-powered air rifles, so I thought that might carry over to pistols.
Apparently, it does, because one of the many groups I shot at 25 FEET was the best of the session. Eight pellets went into a group measuring 0.928 inches.
Although this group is the smallest of the test, don’t be mislead by the appearance. There is a ragged hole at the bottom of the bull to the left of the number six that enlarges this group to 0.928 inches. That’s good, but not that much better than H&N Finale Match Pistol pellets.
Here is another target shot with JSB RS pellets that will fool you. It looks great, but a stray shot that cuts the five-ring (to the right of the dime) enlarges what looks like a tight group to 1.342 inches.
What is the conclusion?
Is the S&W M&P pistol capable of one-inch groups at 23-24 yards? Of course not. It would be one of the most accurate pellet pistols on the market if it were. But at 25 FEET it is more accurate than I expected. Especially with JSB RS domes and H&N Finale Match Pistol pellets. This gun wants to group.
I didn’t shoot at 25 yards because there is no point. It will probably group eight shots in the 3-5 inch range if everything is done right and the best pellets are used. I don’t think this pistol gives us any surprises other than it is very capable for a blister-packed air pistol.
At the price, I doubt you’ll find a more accurate pistol capable of shooting both BBs and pellets — and that says something. With Christmas coming soon, maybe this is one for your gift list.
Pellet velocity versus accuracy test: Part 3
by B.B. Pelletier
Announcement: Jerry Strong is this week’s winner of Pyramyd Air’s Big Shot of the Week on their facebook page. He’ll receive a $50 Pyramyd Air gift card.
Jerry Strong, winner of the Big Shot of the Week, holds a Stoeger X50 and wears a Beeman P1 on his hip.
What a day we have before us! I relearned a valuable lesson in accuracy and got some very surprising results.
Increasing accuracy by an order of magnitude
Before I launch into today’s report, a comment I made a few days ago has raised some interest and I thought I would explain it now. I happened to mention that a new loading technique that I was trying on the Ballard .38-55 rifle had given me the promise of an accuracy increase of an order of magnitude. Instead of 10 shots going into one inch at 100 yards, it looks like this new technique will be capable of putting those same 10 shots into one-tenth of an inch at the same distance. Whether I ever accomplish such a feat is immaterial as long as the rifle demonstrates it can do it.
The technique is one I found in the book Yours Truly Harvey Donaldson. He reported on it in the 1930s, and it’s a technique that was used before the start of the 20th century. And this only applies to lead bullets — not jacketed bullets. The technique is to load the bullet directly into the bore of the gun so that it stops about one-sixteenth of an inch in front of the loaded (but bulletless) cartridge. You do this with an empty case into which a hard wood dowel is driven, then cut off one-sixteenth of an inch longer than the end of the case.
Then simply drop the lead bullet into the chamber with the muzzle pointed down and insert the doweled cartridge behind it. A tool with a lever can be made to seat the cartridge deep enough into the rifling that the rifle’s breech can be closed, camming the bullet the last bit of the way into the bore. Extract the doweled cartridge and insert a loaded cartridge behind the bullet.
The loaded cartridge is reused for every shot — thus eliminating one variable. The cartridge is de-primed, the primer pocket cleaned, re-primed, loaded with a light charge of powder (10 grains of Unique for my proof of concept test) and the balance of the case is filled with Cream of Wheat cereal. Shooters have been loading with Cream of Wheat this way since at least the year 1900, and it works. I put a cork wad on top of the Cream of Wheat, and the cartridge is ready to fire. The cream of Wheat keeps the hot gasses from the base of the lead bullet, so you can use very soft lead that fills the bore better.
It takes approximately 5 minutes to go through the entire loading process; but in that time, the barrel has an opportunity to cool down. Thus, giving stability to the rifle. Because it will go back into the same chamber from which it was extracted, it doesn’t have to be resized. I filed a notch on the rim of the cartridge and this notch is oriented to the 12 o’clock position, to allow the cartridge to enter the chamber the same way every time.
As I mentioned in my comment, the first two shots from my clean rifle went about three inches apart, with the next three going into two-tenths of an inch. That’s at 100 yards with open target sights and a bubble level. I will be reporting on this process in much greater detail, and I’ll have photos for you to see what’s going on in a future report; but I wanted to satisfy the curious who have been asking me about what I’m doing.
On to today
Well, the stuff you just read had a lot of bearing on today’s test. You may remember that this is a retest of the four pellets at ultra-high velocity — which is as fast as any spring gun can propel them. The objective of this test is to see if lowering velocity has any effect on the accuracy of these four pellets.
I’m doing a retest because I thought that the first time around I detected some evidence of group shifting as the bore got seasoned to each pellet. Two of the pellets seemed to act that way, while the other two didn’t.
But as long as I was doing the test again, I decided to use the scope level that’s mounted on the Whiscombe rifle I’m using. I have learned from shooting my Ballard rifle, which has a bubble level on the front sight, that leveling the rifle for each shot makes a huge difference in accuracy. However, that’s at 100 yards, and I’m shooting the pellet rifle at 25 yards. Could a level help much there? I wondered, so I tried it.
I shot the pellets in the same rotation as in the first test — lightest to heaviest. So first up was the Beeman Devastator.
Beeman Devastator
You may recall that I selected the Devastator because it’s the kind of hyper-fast pellet I figured guys who buy hyper-velocity air rifles might choose. I didn’t expect it to be accurate, but you’ll remember that it was.
The Devastator was also one pellet that showed no need for bore seasoning. In other words, it was ready to go from shot one. I was prepared today to shoot four pellets (three to season the bore and a fourth to check where the group should be) before moving to a fresh target, but the Devastator shot so well that I didn’t do that. Today’s group is the first 10 shots out of the gun.
Ten Devastators went into this tight 0.743-inch group at 25 yards. This is phenomenal accuracy for a pellet moving over 1,200 f.p.s.!
By leveling every shot, I got better accuracy. This has been proven many times before.
Incidentally, the shot that strayed from the main group was No. 4. But all the others were even tighter than the group size indicates. I hope you can understand why I did not feel the need to shift this pellet after the first three shots.
Devastators still crack like a .22 rimfire because of the sound barrier thing, so they’re not the pellet to use in the backyard. At least not at this velocity. But they’re accurate. In the first test, the group measures 0.903 inches, so this isn’t really that great a reduction, but I do believe that the small improvement was due to my using the scope level on the rifle for every shot.
Crosman Premier lites
Next to be tested was the Crosman Premier lite pellet. In the first test this pellet was the one that gave a huge difference between where the first couple shots landed and the main group went. So I did season the bore with three test pellets and a fourth check pellet, just to see if the group moved. And it did. It moved about a half-inch upward.
What a difference from the first time! The first group of 10 Crosman Premier lites at 25 yards measured 2.385 inches between centers. This one measures 0.778 inches. Seasoning the bore with four warm-up shots before shooting the group made the largest difference, but the scope level also helped.
Beeman Kodiaks
Many of you expected Beeman Kodiaks to be the best in this test the first time. They were good, but not quite the best. Well, this time they turned the tables and made the best group. I seasoned the bore as described with four shots before starting this group; and although it was small, I did see some movement from the first shot to the second. It’s difficult to say whether that was due to seasoning the bore or just general dispersion, so I’ll withhold comment.
Now, that’s a group! Using the scope level, I put 10 Beeman Kodiaks into this 0.633-inch group at 25 yards. That’s way better than the first group that measured 1.055 inches!
Eun Jin
The last pellet I tried was the 16.1-grain Eun Jin dome. In the first test, this was the most accurate pellet, but this time they slipped to last place. Ten went into a group measuring 0.798 inches. However, that’s very close to their first group of 0.755 inches, so they really didn’t change that much — if any. The others just passed them by.
The worst group of this test was turned in by the pellet that shot best last time. Ten Eun Jins went into 0.798 inches at 25 yards.
Bottom line
I now feel confident that I’m getting everything this rifle has to offer from these four pellets at this velocity. Seasoning the bore remains iffy. It seems to help Premiers, but pure lead pellets don’t seem to need it as much — if any. However, adding the scope level made a big difference in group sizes.
Now the bar has been set; and according to my expectations, it’s set high. Every time I run this test, I’ll have to shoot my very best if the results are to mean anything.
Smith & Wesson M&P 45 air pistol: Part 2
by B.B. Pelletier
Smith & Wesson M&P air pistol is highly realistic. It shoots both pellets and BBs.
Today, we’ll look at the velocity of the Smith & Wesson M&P 45 air pistol. Of course, this pistol shoots both BBs and pellets, so we’ll have to look at the velocity for both.
Two different clips
I told you in Part 1 that the pistol uses two different clips — one for BBs and the other for pellets. It’s important to use the correct clip for each type of ammunition to avoid feeding problems and possible jams. I’ll start with BBs
BBs are pushed into the black plastic clip from the side that doesn’t have the ratchet teeth. The BBs are held in by pressure, alone, so loading them correctly is important.
Unusual stability!
For what I think is a first, I noticed no difference in velocity between single-action and double-action firing. Double-action is when you just pull the trigger to fire the gun. The trigger cocks the striker and advances the clip to the next chamber, so the pull is heavier though, on this pistol, it isn’t that bad.
Single-action is when you cock the pistol separately before the shot. That can be done by pulling back on the rear half of the slide. You won’t find it in the manual, but it’s there and the trigger becomes much easier to pull. Do it when you want to shoot accurately, as opposed to fast.
Trigger-pull
The pistol fires at between 5 lbs., 4 oz. and 5 lbs., 9 oz. on single-action and more than 12 lbs. on double-action. That may sound like a lot; but if you’re a shooter who pulls a lot of triggers, it isn’t so bad.
I shot Daisy zinc-plated BBs, because extensive testing has shown them to be just a little larger than Crosman Copperhead BBs and, therefore, more accurate and a little faster.
Eight BBs (what fits in one clip) averaged 345 f.p.s. As I said, it didn’t matter whether they were fired single-action or double-action. The spread went from 340 to 351 f.p.s., and I was allowing about 10 seconds between each shot. At the average velocity, the gun is generating 1.35 foot-pounds of energy at the muzzle.
Now for pellets
When shooting pellets, we use the gray metal clip. Pellets are loaded from the side that has the ratchet. That’s just the reverse of the BBs. Load the pellets point or nose first and seat them so their skirts are flush with the clip so there won’t be any jams.
The first pellet I fired was the Crosman Competition pellets — a very appropriate pellet for a pistol like this. Eight pellets averaged 334 f.p.s., ranging from a low of 329 to a high of 348 f.p.s. The average muzzle energy was 1.96 foot pounds with this pellet.
Next, I tried RWS Hobbys, which are among the very lightest of pure lead pellets. They also averaged 334 f.p.s., but the range was much broader. It went from 316 to 344 f.p.s. I attribute that to the tight fit of the pellets. The gun was much harder to cock and shoot with Hobbys, as well, so they are not a good pellet for this pistol. At the average velocity, the muzzle energy was 1.73 foot-pounds.
Finally, I tried an H&N Finale Match Pistol pellet. They averaged 351 f.p.s. with a spread from 345 to 359 f.p.s. At the average velocity, they were producing 2.07 foot-pounds of energy, making them the clear leader for efficiency among the pellets tested. They also fit the chambers better, and I think that has a lot to do with how fast they went relative to the Hobbys.
How many shots per cartridge?
How many shots you get from a CO2 cartridge is always something buyers want to know. The M&P seems to be right in where all the other BB pistols are. I got 56 shots before the velocity dropped below 300 f.p.s. with Finale Match Pistol pellets. I shot a final clip of eight — making 64 shots in all. The lowest velocity I saw was 272 f.p.s. with Finale Match Pistol pellets. But you must remember that I was allowing the gun 10 seconds between shots to warm up. Shoot it fast, and you’ll drop below 300 f.p.s. sooner than I did.
Observations
So far, this pistol is doing well. But I’m still intrigued by that one owner who claims he can shoot one-inch groups at 23-24 yards. Part 3 should be very interesting!
Pellet velocity versus accuracy test: Part 2
by B.B. Pelletier
Today, I’m testing the accuracy of my Whiscombe running at full bore. This is the end of Phase One of this experiment. Next time, I’ll reduce the velocity of the rifle and retest all four pellets.
The shooting was done indoors at 25 yards. The Whiscombe is scoped with a Simmons 4-12x scope, and I did use the artillery hold, even though the rifle is recoilless, because John Whiscombe told me to.
Beeman Devastators
KRAAK! That’s what the Beeman Devastator pellet says when it goes downrange at 1,200 f.p.s. It sounded as loud as a .22 long rifle shot, though I’m sure it wasn’t.
I was all set to show you a blown group and then lecture you about the evils of diabolos breaking the sound barrier, only these pellets didn’t seem to cooperate. They all wanted to go to the same place, which upsets all sorts of apple carts.
How about that! Apparently, these Devastator pellets missed the memo that they aren’t supposed to be accurate at high velocity. The 10-shot group at 25 yards measures 0.903 inches. While it’s not a super group, it’s also not bad for a hunting pellet going 1,200 f.p.s.!
Crosman Premier lites
Next up are the Crosman Premier lite pellets. They had the good manners to behave as a diabolo pellet should, by grouping 10 shots in 2.385 inches. Though only a single pellet opened the group to that size, the other nine were still more scattered than the Beeman Devastators.
Crosman Premier lites show the blown pattern of velocity that’s too high. Ten pellets made this 2.358-inch group at 25 yards.
The Premiers also broke the sound barrier, but the sound wasn’t as loud as the Beeman Devastators. I’m thinking the Devastators were also detonating, which is something the JW75 hardly ever does.
Beeman Kodiaks
If you will recall, Beeman Kodiaks brought the rifle’s velocity down to just under 1,000 f.p.s. That’s still in the transonic region and too fast for optimum accuracy — at least according to the popular theory. Kodiaks turned in the second-largest group of this test, though it was much closer to the best group than to the worst. Ten pellets went into a group measuring 1.055 inches.
Beeman Kodiaks didn’t do too bad, considering the velocity they were travelling. Ten went into this group, which measures 1.055 inches between centers.
Eun Jin heavies
The last pellets I tested were the 16.1-grain Eun Jin pellets. Usually, I think of Eun Jins as an okay pellet that delivers maximum power; but in the JW75, which is a spring-piston rifle, they’re the weakest by a considerable margin. However, they’re also down out of the transonic region where all the bad things happen, so I guess I shouldn’t be surprised when they turned in the best group of the test. Ten pellets went into a group measuring 0.755 inches, or just about three-quarters of an inch. And 7 of those 10 pellets went into a smaller group that measures just 0.413 inches across.
Not bad! Ten Eun Jins made this group, which measures 0.755 inches between centers; and seven of those pellets went into the tight 0.413-inch group on the left.
An observation
While I was shooting, I noticed that with both the Premiers and the Eun Jins, the first few pellets landed away from the principal group. That lends a lot of support to the viewpoint that barrels have to be conditioned by shooting a few pellets through them before they can be expected to perform at their best.
A resolution
As a result of this observation, I’m going to run this exact test one more time with a slight change. Before I shoot a group for the record, each new pellet will be fired three times. That way I can be sure we’re seeing the absolute best this rifle can give us at this power level with these pellets.
Surprise!
I was very surprised by the performance of the Beeman Devastators. They didn’t act as I felt sure they would. And I will be very curious to see what they do in the next test. I don’t know what’s happening, because I’ve seen high velocity scatter pellets in the past; but perhaps the introduction of the Whiscombe has changed something. We shall see.
Pellet velocity versus accuracy test: Part 1
by B.B. Pelletier
Welcome to the test that blog reader Mel inspired last week when he made the following comment about whether pellet guns can be overbore:
I live in Germany, where all airguns are limited to 7.5 joules (5.6 fpe). This is very annoying for long-range shooters and also limits the choice of airguns, as many models are not offered in low-powered versions. But the big advantage is that the beginners here get an airgun they can actually shoot precisely, while so many Americans buy one of these $200, 1600 fps bangers just to become disappointed because it acts like a supersonic water hose.
Ask yourself how much power you really need and have a look at the Brits that hunt anything up to rabbits with 12 fpe. I personally would never sacrifice accuracy or comfort to exceed these 12fpe, unless I had a really good reason for it.
That got me thinking about something that’s been banging around in my head for a long time. Pellet accuracy versus velocity. Today, I’ll begin a long test to show if there is such a relationship.
I really wanted to write this as if I were a new airgunner who just bought his first airgun, but then I thought about all the confusion Orson Wells caused with his 1939 radio broadcast, despite continuous disclaimers that it was just a theatrical portrayal. It’s doubtful that my experiments with pellet velocities will cause a panic on the East Coast, but a new reader who finds this series a year from now might become very confused. For that reason, I’ll remain in character.
I’m testing the purchase of a .177 screamer breakbarrel spring rifle to see what kind of accuracy we might expect to get. But instead of any of the possible guns that could be selected, I’ve substituted my Whiscombe JW 75 in its place. So let’s clear the air about all the differences right now.
This JW 75 will serve as a testbed because the power can be changed while leaving all other factors the same.
All the differences
First, the Whiscombe has a premium barrel made by Anschütz. So that will be different.
Next, the rifle has the Harmonic Optimized Tuning System on the barrel. The HOTS allows me to move a weight to “tune” the barrel’s vibrations to the best place for each pellet I use.
Third, the Whiscombe is recoilless. Even though it generates almost 30 foot-pounds in .25 caliber (it has four interchangeable barrels, too), it does not vibrate much more than an FWB 300 match rifle.
Fourth, the rifle is both an underlever and a breakbarrel. The underlever requires three pulls to cock the rifle one time, with a combined force requirement of around 100 lbs. Two powerful mainsprings are pulled back so they oppose each other with a 75mm space between the two piston seals. The barrel also breaks open to load the pellet into the breech.
Fifth, the trigger is in the match-rifle class.
And, finally (I hope!), the rifle has an air transfer port limiter that lets me adjust the power as needed. It’s this final feature that caused me to choose this rifle as my testbed.
So, I’m shooting an air rifle with accuracy potential way beyond that of a $350 mega-blaster. But that won’t matter because of how the test will be conducted.
First, I’ll shoot the rifle at its full power potential. That starts today. Then, I’ll shoot the same pellets I test today for accuracy at 25 yards. I will not adjust the HOTS at any time. It’ll just be wherever it is when I installed the .177 barrel, and there it will remain. That will give us a performance baseline.
Next, I’ll install an air transfer port limiter and test the rifle with the same four pellets shooting through the exact same rifle at a lower power level. That second test will be conducted in the same way — velocity of the four pellets first, followed by their accuracy at 25 yards.
Then, I’ll install a different air transfer port limiter to further reduce the rifle’s power. Another set of tests will follow. By that time, we should know if a final round at the lowest possible velocity would be required or not.
What we’ll get out of this is a view of how velocity affects accuracy, with all other variables remaining the same. That will probably suggest other tests that will further advance our understanding of the accuracy equation.
Let’s start with what I’ll call Phase One — the first test of accuracy and power and test four pellets for power.
Beeman Devastators
I selected the Beeman Devastator pellet for several reasons. At 7.1 grains, it represents the kind of pellet a new shooter would select in the hopes that his rifle will shoot absolutely flat, and he won’t have to worry about ballistics because the pellet never drops. You see the same thing among handloaders who pack dynamite in their cartridges behind finishing-nail bullets in the hopes that they will be shooting a laser. The fact that they’ll really be shooting a chaff gun never dawns on them until they try what they have been envisioning for so long. So, for all those armchair sportsmen out there, I picked this one for you!
The other reason I picked the Devastator is because of the neat design. The pellet looks like it wants to blow up on target. We’ll see about that, won’t we?
In my “Forget the dilithium crystals, Mr. Scott, give her all she’s got” tune, the Whiscombe averages 1,216 f.p.s. with 7.1-grain Devastators. The spread went from a low of 1,205 f.p.s. to a high of 1,233 f.p.s., so the spread is 28 f.p.s. That’s actually pretty stable for a spring rifle shooting at this level. The average muzzle energy is 23.32 foot-pounds, which is pretty hot for a spring-piston rifle in .177 caliber. Okay, we’ll store that velocity away for later, when we test the accuracy of this pellet.
Crosman Premier lites
The second pellet I tested was the Crosman Premier lite. I included them because they’re a classic domed pellet, and I wanted them to be in this test. Why didn’t I test the 10.5-grain Premier heavies? Because they’re more often best in PCPs and not in spring rifles. This was just a judgement call and not necessarily the right thing to do. But that’s the way I went.
Premier 7.9-grain pellets averaged 1,134 f.p.s. in the test rifle. The range went from 1,128 to 1,140, for a 12 f.p.s. spread. This is where the good manners of the Whiscombe show through, because at that velocity a 12 foot-second spread isn’t usually seen in a spring rifle. The average muzzle energy was 22.56 foot-pounds.
Beeman Kodiaks
Beeman Kodiaks weighing 10.20 grains were an obvious choice, given the power expected in this rifle. They averaged 992 f.p.s. and ranged from 979 to 1,001 f.p.s., for a 22 foot-second spread. At the average velocity, they generated 22.29 foot-pounds of muzzle energy. According to my experience and beliefs, that’s still too fast for the best accuracy, but we’ll see.
Eun Jin
The fourth pellet I chose (Buy three — get one free) was the 16.1-grain Eun Jin. I figured that they would be heavy enough to lower the velocity into the accurate zone. And they were! They averaged 726 f.p.s. with a spread from 719 to 732 f.p.s. They averaged 18.85 foot-pounds of energy at the muzzle. We’ll see how well they do on paper in the next test, but I must say this — of all the Eun Jins I’ve ever shot, these fit the breech the best. They slid in like any other pellet.
These four will be the pellets I’ll use throughout this test. We’ll compare them for power and accuracy as I adjust the power of the rifle downward in steps from today’s baseline.
Just looking at the results of today’s test, one thing stands out. The classic spring-piston power relationship popped out exactly as expected. Spring-piston guns are usually the most efficient (the most powerful) when the lightest pellets are used, and that’s exactly the way these four pellets are distributed. That relationship will probably remain the same throughout the test, though the close ones may switch back and forth a little.
I’m going to run the second part of this Phase One test very soon so we can keep the data straight in our minds.
Smith & Wesson M&P 45 air pistol: Part 1
by B.B. Pelletier
1
Smith & Wesson M&P air pistol is highly realistic. It shoots both pellets and BBs.
Today, I’ll start looking at the Smith & Wesson M&P 45 air pistol from Umarex. This is a CO2 pistol with a rifled barrel that shoots both BBs and pellets, so I know there will be a lot of readers who’ll like it. This type of air pistol is becoming more popular all the time, and nowadays a maker can use synthetics in their guns because the firearms they copy also have them.
The gun’s price is low; and according to the one review posted on the website, it’s also accurate. No, make that highly accurate, because the reviewer said he shot out a one-inch bullseye at a range of 22 to 24 yards. I find that difficult to imagine, because I would have a hard time shooting that well with a .22 target pistol, but you know I’m going to put this pistol through its paces. If it really is that accurate, this will be a best buy!
Secrets revealed!
The pistol is all synthetic on the outside. The slide is split in the middle and the front half goes forward to load the pellet or BB clip when the slide release located on the left side of the frame is activated. But a little secret that the owner’s manual doesn’t tell you about is that the rear half of the slide also moves. Pull is backward when you want to fire the gun single-action. The rest of the time, you can just pull the trigger and shoot double-action.
Read the manual
The two clips are not interchangable. The pellet clip is gray metal and the BB clip is black plastic. They are properly called clips and not magazines, because they simply hold the rounds and don’t have springs to move the ammunition in the gun.
Each clip is loaded differently; and even if you don’t read the rest of the owner’s manual, at least take the time to read how to properly load each clip. It’ll save you down time with the gun.
Each clip is for a different type of ammunition. Read the owner’s manual!
Sights are nice
The sights are tactical with three dots — one on the front post and two in the rear — one on either side of the rear notch. They’re bright yellow, and I find them quick to acquire.
The front post is also square in the rear notch, so it can be used with some precision if the lighting is right. That would be with the gun in the dark and the target brightly lit. There isn’t much room on either side of the front post, so you’ll have to work to keep a sliver of light on both sides.
The rear sight adjusts sideways for windage. A locking screw holds it in place.
The CO2 cartridge goes into the grip, of course, but the way it does is novel. You pull down on the front of what would be the magazine floorplate and the “plate” swings down, but the grip strap also swings up and away from the gun. The grip accepts the new CO2 cartridge, and the floorplate hides the CO2 tension screw.
The way the CO2 cartridge installs is a bit different!
The safety is a bar on the right side of the frame that gets pushed forward and up for fire and forward and down for safe. Pushing forward unlocks the bar so it’s free to move. On other pistols I’ve tested, this bar was hard to move; but on this one, it works as it should. On the firearm M&P, the safety is a thumb lever on both sides of the frame for ambidextrous operation.
This is a large pistol but not a heavy one. It weighs less than a pound and a half (24 ozs.), while the firearm it copies weighs almost six ounces more when empty.
A Picatinny rail is cast into the underside of the frame, so you can mount tactical flashlights and lasers. No doubt a great many owners will want to mount at least one of those on this pistol because of the tactical connection. Just make sure your holster can hold the accessorized pistol, as the extra light will add a lot of bulk in the front.
This looks like a good pistol. The trigger is light in the double-action mode and also in single-action. Of course, it’ll take an accuracy test to tell the whole tale. We’ll get to that after we look at velocity for both kinds of ammunition.
