Quackenbush .25 pistol: Part 2

by B.B. Pelletier

Part 1

Test data and photos by Earl “Mac” McDonald

Nobody played!
First of all, we got no answers on last Friday’s question at the bottom of the blog. The answer is: it’s a catapult gun, and it shoots steel BBs. It was offered by the same company that built the Johnson semiautomatic rifle that was used as an alternative by the Marines in World War II, but at the price of $15 in 1948, it never stood a chance.

Today, we’ll shoot the Quackenbush .25 pistol for velocity and accuracy. There was a surprising amount of interest in this pistol, though much of the talk took place on Pyramyd Air’s social network sites. But even here, many readers know about this airgun. Just as a reminder, this isn’t a fire-breathing PCP. It’s a CO2 gun that uses the same stock valve as a Crosman 2240.

This pistol bloops them out at less than 400 f.p.s. because it’s a .25 and shooting pellets far heavier than the valve was designed to handle. Mac says he loves watching them arc out through the scope and drop through the aim point at the last instant. When the sun is behind you, it can be quite a show.

Velocity
We’ll start with the velocity first. A couple of readers guessed that this pistol would shoot under 400 f.p.s. and they were right. The fastest average velocity Mac recorded came from Diana Magnum pellets — an obsolete brand that used to be the best .25 caliber pellet on the market. Until now, Mac has found that it shot best in this pistol. Although Diana Magnums came in both 20- and 21-grain weights (they varied over time), Mac says these weigh an average 19.90 grains, so these are the lighter ones.

Because this is a CO2 gun, Mac had to allow for cooling — so he waited 15 seconds between each shot. That allows the gun to warm up. He also replaced the CO2 cartridge after 24 shots, even though he says the gun gets up to 40 shots per cartridge. That gave every pellet the best chance to perform.

Mac recorded an average 378 f.p.s. with this pellet. The total spread was 7 f.p.s., which is pretty tight for such an inexpensive airgun . At the average velocity, this pellet generates an average 6.32 foot-pounds of energy at the muzzle. Because this is a gas gun, it’s probably going to get more energy from heavier pellets.

Next up was the Beeman H&N Match wadcutter pellet. Weighing 21.6 grains, they averaged 370 f.p.s., with just a three foot-second spread. The muzzle energy was 6.57 foot-pounds.

Mac upped the ante with one of the two new .25-caliber pellets. The Benjamin dome weighs 27.8 grains, so it’s a heavier pellet in this caliber. It averaged 323 f.p.s. with a 7 f.p.s. total spread. The muzzle energy was 6.44 foot-pounds, so less than you would predict; but because it’s a Benjamin pellet, there’s antimony in the alloy, and that may slow it down just a little.

I told Mac that this pellet and the next one are the two most accurate .25-caliber pellets on the market. I expected both of them to beat the Diana Magnum in his pistol.

The final pellet he tried was the new JSB Exact Kings that weigh 25.4 grains. This is the other very accurate pellet that Mac tested. It averaged 346 f.p.s. and generated an average 6.75 foot-pounds. The total velocity spread was 9 f.p.s.

Okay, now the velocity testing is out of the way, and what do we have? The pistol averages under 400 f.p.s. but over 6 foot-pounds of energy. So, it isn’t a weak air pistol. Slow, perhaps, but not weak. So, how does it shoot?

Accuracy testing
Mac shot the pistol at 25 yards. I asked him to shoot 10-shot groups instead of the five he used to shoot with this gun. That made a difference in the group sizes, of course. But another dynamic emerged during testing that I think you’ll find very interesting. I’ll explain it as we go.


Ten shots at 25 yards. Believe it or not, the first four shots are all strung apart from the main group, where the last six shots went. Group measures 2.16 inches between centers.

Do you see the dynamic? The group forms around the final shots. Mac did “season” the bore between targets with two shots from each new pellet; but, even so, the pellets walked into the group at the end of each 10-shot string. I suggested to Mac that this might be due to seasoning the barrel, but he thought it was because the gun cooling down as it was shot.

The heavy JSB Exact Kings were next up. Mac found them to also string vertically for the first three shots, then bunch together at the end, just like before.


Ten JSB Exact King domed pellets made this 1.09-inch group at 25 yards. The first three shots are vertical, then the final seven are bunched together below. There’s one straggler out to the right, but this is a much better group than the wadcutters produced.

Thus far we have seen an interesting dynamic of the pellets moving to a place, then grouping tightly. So how do the formerly most accurate Diana Magnums react? They’re next.


The Diana Magnum pellets didn’t act like the first two pellets. They all landed at the same height on target, without an vertical stringing. Group size was 1.09 inches between centers.

The Diana Magnums don’t seem to follow the same pattern as the first two pellets. I don’t know why that would be, but that’s what the target shows. As with all other pellets, Mac seasoned the bore with two shots before this group was fired. Let’s go to the final pellet and see what happens.


The Benjamin domes gave the smallest group of ten shots at 25 yards. Group measures 0.85 inches between centers. Again, we see a vertical orientation to the group; though, this time, Mac didn’t indicate that the final shots were all bunched together in the large hole.

The results
There you have it. That’s what this Quackenbush .25 can do.

In my opinion, Mac should pick just one pellet — the Benjamin dome — and shoot nothing else in this gun. I think the tighter groups at the end are due to seasoning the bore; because in my other testing, I’m starting to see very similar results. But even if that isn’t what’s happening here, the Benjamin dome is still the accuracy champ.

Is the Quackenbush conversion a good thing for a Crosman 2240? If you want a .25-caliber air pistol and you don’t want to get into high-pressure air, then I guess it is. You must accept the low velocity, while realizing that this pistol is still a good deal more powerful than a Beeman P1. And because it’s launching very heavy pellets, it retains more of that energy longer downrange, so things keep getting better the farther the target is from the muzzle — within reason.

This much is certain — people love tinkering with their Crosman airguns, and Dennis Quackenbush has provided the means to do that for over a decade and a half. This may not be the only game in town, but it’s certainly one of the very best.


The Quackenbush .25-caliber conversion is a neat way to customize your Crosman 2240.


Quackenbush .25 pistol: Part 1

by B.B. Pelletier

Test data and photos by Earl “Mac” McDonald

Back in the 1990s, Dennis Quackenbush made a nice part of his living by modifying single-shot pistols from Crosman. In those days, there weren’t as many places to buy aftermarket parts, and Crosman didn’t have a custom shop. In fact, when Dennis and I were seated with Crosman’s CEO at an NRA Airgun Breakfast at the 2001 NRA Annual Meetings and Exhibits in Kansas City, Missouri, we introduced ourselves and he asked both of us what we did. Dennis told him that he made his living modifying Crosman single-shot pistols. “You sell them (the SSP 250) for $39 and I modify them for $125. I can’t keep up with all the work!”

To say the man was stunned is an understatement. I don’t think he believed Dennis, because he restated what Dennis had said, “You mean people pay you $125 to modify a gun that sells for $39?” You could hear the disbelief in his voice.

That man didn’t remain at the reins much longer. And his replacement, Ken D’Arcy, instituted the Crosman Custom Shop a few years after he stepped in. But that did not diminish the number of aftermarket places that modify Crosman airguns and make parts for owners to install. If anything, the number of places increased, though I would not say that it was in response to the Crosman Custom Shop starting up. But it was and still is a direct result of the openness of the Crosman Corporation toward their customers, by providing parts and information that support their guns.

For several years, one of the most popular modifications Dennis made was a steel breech for the Crosman 2240 single-shot pistol. Not only is it stronger and more rigid, it also allows for the installation of a scope — something that most home tinkerers will want to do. And Dennis switched the bolt handle to the left side for right-handed shooters, because they want to continue to hold onto the pistol while they load it. People who don’t shoot these pistols don’t understand that desire, but it only take 15 minutes with one and you understand completely. That one change may have been his greatest contribution, because it showed everyone what a little thought can do to enhance the operation of an inexpensive airgun!

Many of the handguns Dennis built on Crosman frames are righteous thumpers, with power levels far beyond anything Crosman ever envisioned. Dennis has made several guns on this 2240 frame that achieved 100 foot-pounds of energy at the muzzle, and I’ve personally witnessed one that produced 300 foot-pounds. So, like the modern AR, there’s no limit to what you can do with one of these flexible air pistols.

But in this report, we’re going to look at something a little closer to the original gun. It’s a .25-caliber pistol that has the steel receiver from Dennis and a 10.5-inch barrel that he rifled. In terms of power, it’s been left pretty close to original; so it gets a decent number of shots. Because of the large caliber, they don’t go very fast.


The Quackenbush .25-caliber pistol is built on a 2240 frame. It has a steel receiver, and the bolt is on the left side for easier loading.

There are no open sights, as Dennis envisioned owners would want to scope the gun. The receiver has an 11mm dovetail cut into the top. Since the frame is from a 2240, it readily accepts an add-on carbine stock that so many shooters seem to prefer. Certainly, when you put a heavy rifle scope on the pistol, the stock is the best way to go!

Mac reports that the pull length with the carbine stock is 16.3 inches, but the angle of the grip makes it feel shorter. He says it fits him well, and he usually likes a rifle with a pull length of 13 inches. I looked at the pictures he sent and see that the scope hangs back behind the receiver on this gun. That may be why the long pull doesn’t feel so bad. Also, the gun is very light, at only 48 oz. in the scoped pistol configuration, so there’s not a lot of weight hanging out front. The shoulder stock adds another 13 oz.


The optional shoulder stock is something nearly all pistol owners have.

Dennis didn’t number all of the guns that he made, but partway through the production he began to put his own serial numbers on them. His last gun carried the number 850. Mac’s pistol is numbered 509.

Though Dennis no longer makes complete guns, according to his website he still does make the parts for them so owners can modify their own guns. The velocity of the .25-caliber pistol is approximately the same as the 2240 that it was modified from when shooting a 14.7-grain .22-caliber pellet.

The features of this modification are:
Steel barrel, receiver and bolt
The barrel is threaded into the receiver
The transfer port is in the breech instead of the barrel
The new steel bolt is larger than the pellet
The bolt contacts the pellet’s skirt — no probe is used

The pistol is 14 inches long without the shoulder stock, and 26 inches in the carbine configuration. The trigger-pull is a repeatable 43 oz., though some may find the trigger blade a bit too thin for comfort. The scope you see here is a cheap Simmons that Mac thinks was probably a rimfire scope at one time. It has a one-inch tube and fixed 4x magnification. The 32mm objective lens has a fixed parallax that Mac adjusted to 25 yards by turning the lens locking ring.

While many .25-caliber single-shots produce lots of muzzle energy, this isn’t one of them. Those guns are modified into PCPs, where this one is still a CO2 gun. It gives you a taste of a larger caliber without all the extra fuss and noise that a magnum blaster would have.

Mac tells me this pistol is quite accurate, and he loves the way it lobs them in. Next time, we’ll combine Parts 2 and 3 for a good look at the performance of this vintage Quackenbush airgun.


With the longer barrel and no open sights, this pistol looks slicker than the 2240 it was modified from.


Quackenbush .308: Part 4

by B.B. Pelletier

Part 1
Part 2
Part 3


Quackenbush .308 big bore is an attractive airgun.

The last time we looked at this Quackenbush .308 big bore was when I discovered that my rifle really likes Mr. Hollowpoint’s 68-grain hollowpoint bullet. I also tested a 150-grain Loverin-design bullet that was just a bit too heavy for the gun. It didn’t want to stabilize and was tearing elongated holes in the target at 50 yards.

If you’ll recall, I was running low on air that day, so I could fill the rifle to only 3,000 psi. That gave a stunning group that was smaller than one inch at 50 yards with the 68-grain hollowpoint, but I wondered whether it would do any better if I filled the rifle to higher pressure. I also wondered if going just a trifle faster would have stabilized the 150-grain bullet. There were a lot of unanswered questions after the last test.

Today, I’ll address those questions. I had a full air tank and a reasonably good day at the range. Certainly for testing something as stable as a .308, the light breeze was no challenge.

Shooting the 68-grain hollowpoints
I decided to fill the rifle to 3,500 psi, to see what kind of velocity that might give. The 68-grain bullet averaged 1051 f.p.s, on that much air and left about 3,100 psi in the tank for the second shot. That’s a muzzle energy of 167.15 foot-pounds.

Shot two averaged 1,010 f.p.s. with the same 68-grain bullet and generated 154.07 foot-pounds of energy. You might think that’s close enough to the first velocity that the bullets will print in the same place. They might if this was a firearm — but it’s an air rifle, and we have to take the flexing of the horizontal air reservoir into account. As the pressure inside the air reservoir changes, the reservoir — which is a long tube — flexes a tiny bit. Since it’s connected to the barrel, this flexing can cause movement in the muzzle.

The first shots printed about two inches higher on the target than the second shots. I knew they would from past experience shooting other big bores, so this came as no surprise to me. I actually shot one group of first shots (after a 3,500 psi fill) at one target and a separate group of second shots at a second target.

After seeing where the shots landed relative to the aim point, it’s possible to use the mil-dot reticle in my scope to shoot both shots into the same group by using two different aim points. This is a technique I learned several years ago with my .458 Outlaw; and with it, I can put five bullets into one inch at 50 yards. I didn’t try that on this day, however, because I was too busy learning the gun.

Neither group obtained this day was as good as the group I shot last time on just 3,000 psi of air. The first group that was shot on 3,500 psi measured 2.72 inches between centers for five shots, though four of those shots landed in a group measuring 1.219 inches.


Four of the five bullets were close at 50 yards on 3,500 psi. Two landed in the same hole.

The group that was fired on 3,100 psi measured 1.953 inches between centers. That’s twice the size of the best group that was shot several weeks ago on 3,000 psi, so I think this bullet is going too fast for best results. It looks to me like this 68-grain hollowpoint wants no more than 3,000 psi as a max charge. That would put the velocity at around 970-980 f.p.s.


Lower starting pressure gave a tighter group. This one was made with 3,100 psi.

Did the 150-grain bullets stabilize?
Again, the 150-grain bullets failed to completely stabilize — even when driven to 825 f.p.s (on 3,600 psi air) and generating 226.75 foot-pounds of energy at the muzzle.


Both bullet holes show evidence of tipping. The bullet is not stabilized.

Clearly, this Loverin bullet is too long to stabilize at the velocity this rifle generates. What’s needed is a 120- to 130-grain bullet that’s short, which means it must have either a round or a flat nose.

Some observations
I’m seeing a relationship between soft pure lead bullets and better accuracy. Any hardening alloy seems to open up the group.

Ditto for lubricated bullets. So far, the best, most accurate bullets are those that are completely dry. I see now that I need to cast some more 130-grain bullets in lead that is as pure as I can make it, and shoot them absolutely dry. I’ve seen the performance of pure lead bullets on game, and they hold together far better than hard alloy bullets do. Lead hardened with antimony breaks apart in large chunks, while soft lead mashes up like a wad of bubble gum when it hits game.

I’ve always questioned using a .308 for game as large as a deer. I know hunters who are better shots than I am do it all the time and have great success, but for me the .308 is more of a coyote and bobcat round. I’ll leave the deer and wild hogs to the .458 and keep this .308 for smaller game. It probably has a useful range of 125 yards in my hands. For an air rifle, that’s pretty far!


Quackenbush .308: Part 3

by B.B. Pelletier

Announcement: Tyrone Nerdin’ Daye 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. Congratulations!

Tyrone Nerdin’ Day says this about his winning photo: Me and my IZH-DROZD MP-661k Blackbird with Wild Mod Chip, Walther PS 22 red dot sight, quad rails and a UTG Tactical Op bipod. Black SWAT vest with the Walther CP99 Compact, police belt with Winchester Model 11.

Part 1
Part 2


Quackenbush .308 big bore is an attractive air rifle.

It’s been a long time since Part 2 because I was searching for a better bullet for this rifle. Oh, the groups shown in Part 2 aren’t that bad; but when you see what I have to show today, you’ll be glad I stuck with it.

Most of my experience has been with Quackenbush’s larger calibers. My Quackenbush .458 Long Action rifle is so accurate that I was pretty sure I could get better performance out of this .308.

The .308 is the big bore gun everyone talks about these days. Guys are taking deer and goats with them out to incredible distances. At the 2012 LASSO big bore shoot, they were hitting half-sized sheep silhouettes out to 300 yards and making it look easy. But the bullets I had didn’t seem to want to perform like what I saw from other guns. So, I kept searching and trying different bullets.

Blog reader Robert from Arcade even sent me a batch of 150-grain Loverin-style lead bullets he cast himself. They were big and heavy, and my rifle wasn’t doing that well with lighter lead bullets, so I didn’t have a lot of hope for these. But I took them along to the range yesterday, where I tried them along with a remarkable new bullet that I picked up at the Arkansas airgun show this year.

Mr. Hollowpoint saves the day!
At that show, I asked Robert Vogel, who’s Mr. Hollowpoint, for a good bullet for my rifle. He recommended a new hollowpoint he’s casting that has had some good reports. At 68 grains, it’s a featherweight compared to the 115 to 130-grain bullets I’ve been shooting, and I thought maybe the additional velocity I’d get might make the difference. So, I bought a bag to try.

I got out to the range on Wednesday, and the day was very close to perfect. At 88 deg. F, it was a bit warm, but the wind was very low and never did pick up.


The 150-grain Loverin bullet on the left and the 68-grain hollowpoint at the center and right were both tried. Notice the uneven base on the hollowpoint. It seemed to make no difference on the target. That large hollow point lives up to its name!

My carbon fiber tank would soon need a refill, so I was only able to fill the rifle to 3,000 psi, and I held the number of shots per group to 5 instead of 10. The first shot was low and about three inches to the right of the bull, so I cranked up the elevation and put in some left clicks and then shot a 10. It was nothing but luck that the one adjustment put the bullet in the right spot.

It doesn’t get much better than that, so I refilled the rifle and shot again. I was filling after each shot, so every shot had the benefit of a 3,000 psi fill behind it. With the Quackenbush Long Action Outlaw, and to a large extent with all other big bore air rifles I’ve tested, the first and second shots group in different areas — but they do group tight. The trick is to use some extra elevation for the second shot so it goes to the same place as the first. But since I didn’t know exactly how much elevation to use with this new bullet, I refilled after each shot instead.

It was a slow, methodical process of settling into the rest, sighting, squeezing off the shot, then returning to the tailgate of my truck to top off the reservoir for the next shot. My shooting buddy, who witnessed all this, was impressed by how much recoil this .308 has. Of course, it recoils with or without the bullet, because the air that’s exhausting is giving the rifle a rocket push.

By the time the fifth shot had been fired, I could see the results through the scope. The group was tight and well-centered, and the last three shots were in the x-ring, which is in the center of the 10. They can be covered by a dime. So, this 68-grain hollowpoint from Mr. Hollowpoint is the bullet my .308 likes!


Five shots went into this 0.975-inch group at 50 yards. The 68-grain bullets from Mr. Hollowpoint are a real winner in my Quackenbush .308. The center three bullet holes can just be covered by the dime.

The base of the bullet has an uneven ridge extending past the base. It’s the result of sizing the bullet, because Robert Vogel sizes each and every one to .308. Normally, I would worry about anything on the base that isn’t perfectly uniform; but after looking at the target, I can see that this has little affect on how this particular bullet flies.

This bullet loads very easily in my rifle. There seems to be no resistance when the bolt is closed. They’re cast from pure lead, which leaves them soft and prone to deformation. Performance on game is enhanced through the combination of the soft lead and the hollowpoint design. A soft lead bullet holds together better than one that’s hardened with antimony, so these bullets still penetrate deeply in game. Elmer Keith wrote extensively about the performance of soft lead bullets on game with handguns, and the velocity of these big bore rifles is pretty close to what he obtained.

I wouldn’t use such a light hollowpoint on a whitetail deer-sized animal, but it ought to turn a coyote or a bobcat inside-out! And the rifle is now zeroed at 50 yards — huzzah!

From light to heavy
Next up was the Loverin-style 150-grainer from Robert of Arcade. Since the rifle was only so-so with the lighter bullets I’d tried, I didn’t think it would stabilize this long lead slug, but it wasn’t much trouble to try. Robert also casts these from lead as pure as he can get; so, like Mr. Hollowpoint bullets, they’re just right for airguns.

A Loverin bullet has many grease grooves along a relatively long body. It was greatly in favor in the early 20th century. When jacketed bullets came along, they sent the best lead bullet designs into relative obscurity. Only those who cast their own bullets are aware of the differences in designs like the Loverin, and this style bullet is no longer popular with mold-makers today. If I want to get a Loverin mold, I either have to buy a custom mold or I have to watch the auction sites for a vintage mold to come up for sale. This one is Lyman mold 311466.

In contrast to the easy loading of the 68-grain hollowpoint, these bullets were hard to load. They were not sized and measure up to 0.311 inches in diameter. I normally shoot unsized lead bullets in my big bores whenever I can to ensure the best sealing of the bore — a little resistance at loading is normal.

The bullets landed lower on the target, as expected, and they were about a half-inch to the right; but after 5 shots, I was impressed by the group they made.

By this point, the carbon fiber tank was definitely running out of air. On the final two shots, it filled the rifle to only 2,950 psi. Since the resulting group seems elongated up and down, I will attribute some of that to the uneven fill. I think that if I shot this bullet at a higher-pressure fill, the performance might improve.

Notice, also, that the bullet holes seem elongated. There was some tipping going on, and this bullet is probably at the ragged edge of stability at this velocity — whatever that is. A higher-pressure fill will probably boost velocity enough to correct this at 50 yards.


Five shots went into this 2.008-inch group at 50 yards. The Loverin-design bullet did remarkably well, considering its 150-grain weight. The last two fills were only 2,950 psi. I wonder what a higher, more uniform fill might do?

This longer, heavier bullet would be ideal for deer. While the velocity is probably down at the 700 f.p.s. mark, these bullets still shoot all the way through deer unless they’re stopped by heavy bone. I would restrict my shots to very close range with this bullet, but I think it might do the trick out to 80 yards, or so.

What’s next?
Now that I have one good bullet for sure and the possibility of another, it’s time to test both with higher fill levels. I also want to chronograph these bullets so we can see what sort of performance they give.

I also want to cast some of my 130-grain spitzers in pure lead and shoot them unsized and unlubricated. That might be the secret to success in this rifle.

We’re not quite done with the Quackenbush .308. My thanks to both Mr. Hollowpoint and to Robert from Arcade for providing me with these two bullets to test.


Quackenbush .308: Part 2

by B.B. Pelletier

Part 1


Quackenbush .308 is handsome even in this lowest-grade version.

Today’s report will be quite different from the norm. This is Part 2, which is normally where I test velocity. I did that, and you’ll see it in today’s report — but you’ll also see some targets, because I tested accuracy, too.

When I test a smallbore pellet gun, I know at the start how the gun should perform, more or less. Yes, there are some surprises; and yes, I do make some mistakes — but a lot of what happens can be predicted pretty accurately. But not a big bore!

With a big bore airgun, I’m almost starting from scratch. Sometimes, I will have tested something similar and can use that experience as a starting point, and there’s some of that in today’s report; but this .308 rifle is unlike any other big bore air rifle I’ve ever tested. There are more .308 lead bullet designs and bullet molds available than there are .177 pellet types on the market. Out of all that, I have to select some designs that make sense.

This is where my firearms experience comes in handy, and this is the reason I often run reports on firearms in this blog: learning the intricacies of this Quackenbush rifle is exactly like figuring out how a new black powder rifle operates. And I don’t mean some ultra-modern, bolt-action black powder rifle that uses replica powders in pellet form, either. I mean a real black powder rifle made by hand and has to be figured out as you go.

So, how do you start testing a gun when you don’t know much about it? Well, you start with what you do know and go from there.

I know that other Quackenbush Long Action Outlaw guns operate at pressures above 3,000 psi, so I’ll start with a higher fill pressure. I know that this rifle will be in the 200-250 foot-pound range with bullets it can stabilize, so I’ll select them first. I know that by reading what others have written about their .308 rifles.

I also know that Quackenbush rifles have to break in. They do get faster with use. So, I’ll look for that.

Furthermore, since this is a big bore air rifle operating at a very high level of performance, it’s going to use a lot of air. I know how much air the Korean guns like the .50-caliber Dragon Claw use, and I know that this rifle is going to use even more. So, even an 88 cubic-foot carbon fiber air tank is going to get drained in a hurry.

I cast bullets for many of my firearms, and I also happen to own a bullet mold for a nice spitzer (pointed) lead bullet that was designed for the M1 Carbine. It casts at around 130 grains, which is an ideal weight for this rifle, because the expected velocity (derived from the known power that has been published by other .308 owners) will be 850-950 f.p.s. on the first shot. I calculate this velocity range by taking the expected power (say 225 foot-pounds) and running it through the Pyramyd Air velocity calculator (use the second formula on the page to do this).

The issue here is bullet stability. These bullets are stabilized primarily by the spin imparted by the rifling in the gun. The longer a bullet becomes, the faster it must spin in order to stabilize. Since you cannot change the twist rate of the barrel, you have to drive the bullet faster to stabilize it. Sometimes, though, you’ll get away with shooting targets that aren’t too far away with a longer bullet. The bullet will be semi-stable for the first 40-50 yards or so. It all depends on the bullet’s length.


The bullets I shot are like the one at the center of this photo. At the right is that same bullet with the lubricant wiped off. At the left is a 170-grain lead bullet that’s normally too heavy for this rifle. However, for close work, it might work okay. That bullet normally takes a copper gas check, but it can be shot without one.

That velocity will give a fairly flat trajectory and stability to the 130-grain bullet as far as the rifle can be accurately shot — which is about 200 yards. But consider this: this bullet is just one of over 200 different lead bullets that are appropriate for this rifle! If you really want to experiment and push the envelope, that number grows to over 500! Nothing guarantees that this will be the one right bullet. It’s just the first one I tested.

Scope troubles
Before I went to the range, I mounted a scope on the rifle. I encountered problems right away because of how far the Weaver bases are set apart on the rifle’s action. They are so far apart that I cannot mount the leapers long eye relief scope I had planned to use, because the ring separation exceeds the scope’s tube length. This is where it gets dicey because of the scopes that were available; and the Weaver rings I had that were not committed to other tests and guns. I ended up with a set of high rings and an Osprey 2.5-10×40 scope that I don’t care for. More on that, later.

So, I get to the range and the day is pretty good. The wind is fairly calm, with just a few breezes I can wait out. Besides, I’m shooting a .308 130-grain bullet at 50 yards. The wind doesn’t affect it nearly as much as it would a pellet!

First fill
The gun’s first fill is a guess. I know my .458 Outlaw likes a 3,500 psi fill, so I go with 3,600 psi for this one. I’m looking for a couple things. First, how fast does the first shot go? Second, how fast do shots two through whatever go? That’s right — I don’t even know how many powerful shots I’m going to get from this rifle. If it were a 9mm Korean gun, that number would be 5-7. But a Quackenbush .308 is more powerful and uses a lot more air. My .458 gets two good shots per fill, so there’s a very good chance this one will, too.

Before I left the house, I oiled the striker (hammer) with high-tech gun oil. I oiled it again at the range. I know that all big bore guns need to break in to shoot their best. Then, I filled the rifle to 3,600 psi and started shooting:

Shot……..Vel.
…1……….857
…2……….816
…3……….777
…4……….730


The first few shots were over the chronograph. Then, I commenced shooting for accuracy at 50 yards. You can see how high the scope sits above the receiver.

Okay, those are the first four shots. If I’m looking for good groups at 50 yards with this bullet, only the first two shots look good. If I’m demonstrating the rifle to a bunch of Boy Scouts, I can probably continue shooting for another couple shots. Do you see what I’m doing? I’m calculating things based on what kind of shooting I expect to do.

And shot one generates 212.06 foot-pounds of muzzle energy. Shot two makes 192.26 foot-pounds.

I also noted that when I went to fill the reservoir again, the gun still had about 1,900 psi inside. Four shots used up 1,700 psi, or about 425 psi per shot. The Korean big bores use around 200 psi per shot, so that gives you a good idea of how they compare to a Quackenbush Long Action.

Next, I sighted-in the rifle. Because the Quackenbush Long Action does not allow the bolt to be removed easily at the range, I used a target paper that’s two feet by four feet. The point of aim is close to the center of the paper. That gives me a good chance of striking somewhere on the paper at 50 yards. If this were a smallbore airgun, I would have started at 10 feet, as I explain in my article about sighting in a scope; but you can’t do that with a gun this powerful unless you own a lot of private land. I’m on a club-run rifle range, and I have to obey their regulations. I’m hoping to get on paper without boresighting. I do own a boresight device, but it has only bore spuds that go up to .22 caliber, so it wouldn’t work in a .308.

I’m in luck, because the first shot hits the paper…about two feet below my aim point. Well, that isn’t as lucky as you might think. Remember the Osprey scope I mentioned earlier? Well, it has 1/8 MOA (minute of angle) adjustments. At 50 yards, every click will move the strike of the round about one-sixteenth of an inch! For two feet, I’ll have to move the elevation knob up 16 x 12 x two, which is 384 clicks! There probably aren’t that many clicks in this scope, plus I don’t know how far up it already is. I have a droop problem!

I’ll replace this scope and mounts for the next test, which means I’ll have to sight-in and do this all over again. But today is not lost. I can still continue to test the gun. I adjust the scope up so the round lands about 14 inches below the aim point, and that’s how I will test the gun today. It’s simple enough to staple two targets to the backer in line with one another, so I can aim at the top one and hit the lower one. Now, we can see how this rifle shoots with this bullet.

The only problem is — all I have are bullets that have been sized and lubricated. I know that Quackenbush big bores seem to do best with dry lead bullets, or at least that’s been my experience up until now, but I’ll use the bullets I have on hand. I will have to cast some more bullets and not lubricate them for the next test.

Accuracy
Shot one went about 14 inches below the point of aim, as mentioned already. Shot two dropped another several inches, but I compensated for it by using the tip of the bottom fat vertical duplex reticle line as a different aim point. So, I’m able to get a fair grouping of bullets, though it’s nothing I am satisfied with, yet. I’m able to shoot six bullets into a group measuring 1.6 inches by shooting just two shots per fill and using the two aim points. After shot two, the gun’s remaining pressure is about 2,700 psi, so the first two shots use about 900 psi — which works out to 450 psi per shot. Do you see how this stuff works?


Two bullets in the hole on the left, and you can see the rest. Three of them were first shots after a fill, and three were second shots. This group measures 1.6 inches between centers.

I then moved over to another set of targets and tried something different. I tried refilling after the first shot — so every shot would be going the same speed and I could use the same aim point. This time, four of the five shots grouped into 0.982 inches, but the fifth shot opened it to 1.767 inches. It looked like it was going to be better, but once again, no cigar.


There are three bullets in the large hole on the left. Shot four (top) opened the group to just under one inch, but the fifth shot opened the group to almost 1.75 inches.

After shooting at two different targets, I lubricated the striker again and chronographed the gun. This time, I tried to fill the reservoir higher than 3,600 psi, but my carbon fiber tank had already dropped to 3,600 psi. I had to stick with that as the highest fill pressure.

Shot……..Vel.
…1……….867
…2……….819
…3……….772
…4……….733

As you can see by comparing this second string to the first one, my rifle seems to be performing at the same level, more or less. That does not tell me whether 3,600 psi is the highest operating pressure or not, but it’s a good indication that the rifle either needs a lot more shots through it or it’s already broken in. I’ll have to get my carbon fiber tank refilled before I can conduct another test at a higher fill pressure.

And just for continuity, the first shot generated 217.04 foot-pounds. Shot two generated 193.67 foot-pounds.

Where to next?
If you’re as curious as I am, these results open up a lot of possibilities. For starters I want to test the gun at a higher fill pressure. I also want to shoot dry bullets, but I think I need to clean and dry the bore before I do. I can’t clean the lubricated bullets well enough to consider them dry, so I have to cast another batch.

I definitely have to mount a different scope in lower rings, and I have to be prepared to elevate the rear mount if the rifle turns out to be a drooper. All I know at this point is that I had the scope adjusted very high, which very well could have lead to the groups being as large as they were.

I have a feeling that this rifle will shoot groups smaller than one inch once I learn its secrets.


Quackenbush .308: Part 1

by B.B. Pelletier

Announcement: Rich Mulvey 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! Congratulations!

Rich says that this is Ben, who’s 11 years old. He’s getting ready to shoot the reset paddle on his Gamo trap. He’s using the Air Venturi Bronco.

Today I’ll begin a look at a big bore precharged air rifle that most of you will never see. The Quackenbush .308 is a classic from the central Missouri airgun maker.

This air rifle may not be mainstream; but just mention it to airgun hunters, and you might as well have pulled the starter rope on a hotrod snowmobile! The noise starts immediately as people break up into discussion groups, some to explore the potential accuracy or the best bullet and others to recount the dozens of game animals that have fallen to their rifles.

I’ve personally seen 150-lb. goats dropped at 140+ yards with single shots from this rifle, though I wouldn’t recommend it for that distance or for that size animal. But it did work, and I saw it do that twice in one day. But hunting is the purview of others. I’m going to do my usual review of the rifle and let you readers decide how best to use it.

.308 caliber
Dennis Quackenbush is both a shooter and a hunter. Besides making several hundred airguns each year, this man “gets it.” He knows that if an air rifle is a .45 caliber it either has to be a .451 that can use common pistol bullets or a .458 that uses common rifle bullets. He would never think of foisting a .454-caliber rifle on his customers, because Dennis knows that the .454 pistol caliber died before World War II. As a shooter, he understands the importance of making rifles in calibers for which there are a wide variety of lead bullets, because not everyone casts their own.

He chose the .308 caliber for the obvious reason that it’s the most popular-sized .30-caliber bullet here in the U.S. There are .310 and .311 lead bullets available for the SKS, AKM and the Mosin Nagant — but they’re not that popular. You have to search to find them. But .308 is money in the bank here in the U.S. You’ll find dozens of different styles and weights to try in your rifle.

I once asked him why he didn’t go with 9mm when he brought out this rifle and he responded, “Ballistics. You know there are very few 9mm lead pistol bullets available on the market; and of those, the heaviest is about 125 grains. That gives you a short, fat bullet with low sectional density and poor long-range performance. But in .308, a 130-grain rifle bullet is reasonably long and has a much higher sectional density than the short 9mm pistol bullet. And my rifle can drive a 130-grain .308 bullet up to respectable velocity, making that caliber well-suited for hunters.”


Quackenbush .308 rifle is handsome even in this lowest-grade version.

The rifle
My .308 is made on a Long Action Outlaw receiver. I tested a .308 Exile back in 2005, but the rifle I tested was made on the old action with a shorter striker spring and striker travel. The long action allows the striker spring to be longer and the striker to travel a longer distance. Both increase the airflow through the valve, which equates to power.

My article reviewing the Exile is up on the Quackenbush website, so I’m able to compare the performance of this current long action gun to what was done in the past. That old rifle shot a 128.6-grain bullet at 860 f.p.s. on the first shot — generating 211.25 foot-pounds of muzzle energy. It did take some shooting to get the rifle up to that velocity, as the moving parts do need to wear in a bit, but I’ll also lubricate them before the velocity test starts with the new rifle, which will put me on better footing than I was in the old test.

The rifle is blued steel housed in a figured walnut stock. I selected the lowest-grade gun Dennis makes, but you can see from the photo that it’s still something to be proud of. It weighs 8 lbs. exactly without a scope, and the rifle comes without sights, so a scope is required. It comes with Weaver bases installed, so you need Weaver rings to match.

I’ve used the Leapers Bug Buster scope and other compact scopes in the past on these rifles, but the long action of this particular rifle needs a scope with a longer tube. The plan is to install a long eye-relief scope and see how it works. After my success with the Evanix Conquest at 4x, I’m suddenly interested in lower-power scopes — especially for workman rifles like this.

The rifle is just shy of 44 inches long, and has a 26-inch barrel. The pull is 13-1/2 inches. The action is different from what you may be used to, though it’s not unusual. Dennis uses a separate cocking bolt to retract the striker against the heavy spring, leaving the loading bolt for just the single function of inserting a bullet. This design was popular back in the 1980s with several vintage British precharged rifles but is seen less often today. In powerful big bores, however, it offers the advantage of providing good purchase on the cocking handle, while leaving the loading bolt normal-sized.


The black handle cocks the striker. The knobbed bolt is just for loading.

Dennis makes all his own barrels and the rifling buttons that cut them. At one time when he was experimenting with twist rates, he was hand-cutting the rifling; but now that he has the data he needs, button-rifled barrels are easier and faster to make, as well as smoother after production.

Lead bullets
I’ve made several references to using lead bullets — now let me explain why. In big bore air rifles, you want to eliminate as much friction as possible. Jacketed bullets have too much friction and will slow the velocity way down, plus they wear the soft steel of the barrel much faster. This holds true for vintage firearms, as well, which is why I would never shoot a jacketed bullet in a Trapdoor Springfield or in my old Ballard. People do shoot them in vintage guns, but they’re wearing out barrels much faster than they should.

These older guns have much softer steel in their barrels. While they’ll reasonably give 50,000-100,000 shots with lead bullets if properly cared for, shooting jacketed bullets will wear them out in as few as 5,000 rounds. I’m speaking about firearms now — the airgun barrels do not wear out at the same rate, and nobody knows how many shots they could conceivably get.

Fill pressure
Dennis builds airguns for thinking owners. You don’t just pull one of his rifles from a box and fill it to 3,000 psi. You experiment, which means you need to have access to a chronograph. I’ve found his Outlaw actions can tolerate 3,200 psi up to 3,500 psi very well and give optimum performance. Others have claimed fill pressures up to 3,850 psi in their guns. The point is that you experiment until you find the fill pressure that gives the greatest number of high-power shots with the bullet you’ve selected to use. I’m hoping to get four or possibly five good shots on one fill of this rifle.

Quackenbush rifles all fill from a standard Foster male fittings. He provides a stainless steel fitting to prevent the ball bearings of the female fitting from impressing themselves into the metal of the male fitting at high fill pressures.


The rifle is filled through a common Foster male fitting. It’s very standard around the world.

General
Dennis has very definite thoughts on what makes a good airgun. Though he also builds parts for aerospace companies and test fixtures for other manufacturers, he keeps his airgun technology firmly planted in the 1950s. By that I mean he’s going to use steel for the metal parts and walnut for the wood.

He buys his stock blanks in large lots, so there will always be enough for his production needs. And he shapes the stocks on a pantograph to save time and keep the shape consistent.


Quackenbush always has several hundred walnut stock blanks on hand.

We’re in this together
I have owned this rifle for about four years and have never fired it. My .458 Quackenbush always takes precedence, so this adventure will be just as new to me as it is to you. I’m inviting you to watch over my shoulder as I get to know this classic big bore.


Airgun darts

by B.B. Pelletier

Update on Tom/B.B.: When I visited him Monday afternoon, we discovered that he’d lost 50 lbs. of water in less than a week. All vital signs are stable and things look quite good!

Today’s blog was written by B.B., but we have an announcement first.

Pyramyd Air is having its 3rd Annual Airgun Garage Sale on June 5. As in previous years, there will be a mountain of guns and accessories with slashed prices and dented pellet tins at huge discounts. Come early, bring cash or credit cards, and shop til you drop!

Now, on to today’s blog.


An airgun dart is very accurate due to the high drag of its animal hair or fiber skirt. It’s forward-weighted and has fletching, just like the hand-thrown dart.

Here’s another subject I’ve hit before: Darts in airguns. Back in the 1600s, darts were the most accurate ammunition available for airguns. They were considered for target use only, were very low-powered and were shot from smoothbore guns of approximately .40 caliber. When airgunners see these old guns, they imagine things that just aren’t true, such as shooting them with lead balls, bullets or pellets. The truth is that darts were at one time a very popular airgun ammo.

The progression: from then to now
The early darts were very carefully made with metal bodies and animal hair fletching. Accuracy was controlled by removing hairs from the tail of the dart…one at a time. One hair was always a dark one, and that one never got removed. It was the way you oriented the dart in the barrel of the gun each time you loaded (e.g., always put the dark hair at the 12 o’clock position in the breech).

In the 19th century, they started producing darts with machines. This made them cheaper to buy but considerably less precise. They were still the ammunition of favor until the late 1870s.


The felted slug acted like a modern diabolo pellet.

Henry Marcus Quackenbush
When H.M. Quackenbush brought out his popular line of airguns, he also made darts for them, and that was considered their best ammunition. Later, he brought out several different types of ammo for the same guns. Cat slugs were solid lead cylinders with felt glued to the tail. The felt acted like a modern diabolo waist and flared skirt, creating high drag that kept the slug on track. Later still, some H.M.Q. guns were made to fire modern diabolo pellets and lead balls. Once, again, they were never very fast because of their roots in a dart gun design.

After WWI, the popularity of darts faded quickly. Webley kept them alive for their smoothbore pistols, most notably the Junior model, on which I reported recently. By the 1950s, the concept of the airgun dart was not very well understood in the USA. Benjamin made and sold them for their smoothbore guns that were also BB guns. But, most owners paid no attention and shot the metal body darts in their guns with rifled brass barrels!

You can still buy darts, but not many people do. A good dart gun is very low-powered and a very smooth shooter. Anything else defeats the purpose. They’re not, as some airgunners believe, super-penetration hunting ammunition.

Before I sign off today, I have another announcement.

Oehler 35P now available again
Most of us are more than happy with our Shooting Chronys, but a few of you have asked me for years about getting an Oehler 35P printing chronograph. I’m not here to sell an Oehler to you, but there’s no substitute if that’s what you really want.

The new package includes 3 skyscreens, a skyscreen bar, tripod, chronograph with built-in printer, and diffusers…all packaged in a hard rifle case. The Oehler is the only chronograph I know of that has a second proof channel that constantly compares to the output of the main chronograph channel. Both channels print out on the built-in printer. The price for this package is $575 with shipping (which is an introductory offer). At that price, this product isn’t for everyone. For 95% of my testing for Pyramyd Air, I use a Shooting Chrony.