Airgun History Project | Air gun blog

Diana 75/Beeman 400 recoilless target air rifle: Part 4

Posted on March 1, 2021 by B.B. Pelletier ↓ 28 Comments

by Tom Gaylord
Writing as B.B. Pelletier

The Diana 75.

Let’s make lemonade
Part 1
Part 2
Part 3

This report covers:

Three groups
Taped the targets
Hand-held
Follow-through
Glasses
First group — H&N Finale Match Light
Group two — RWS R10 Match Pistol
A secret
Head sizes and groups
Group three — Vogle Match pellets
Velocity?
Why?
Another accuracy test

Today we revisit the Diana 75/Beeman 400 for a very special reason. You readers thought the rifle didn’t perform up to expectations last time in the accuracy test, and neither did I. So I took every one of your recommendations and applied them today.

Three groups

I only have three 5-shot groups to show you from today’s test. I shot them with the two pellets that did the best in the last test, plus one pellet that I thought might be on the fence. I shot from 10 meters and I’ll tell you the rest as we go. Much of what I will say in this report is for me, for the next time I shoot this rifle.

Taped the targets

To keep the targets from tearing I put tape on their backs. I used aluminum foil tape like Hank recommended on some of the bulls and a white form of duct tape on the rest. The aluminum tape tore the target paper around the edges of each hole and was not as clean as the white duct tape, so next time the white tape is what I’ll use. Just cover the back of each bull and that’s it.

Hand-held

Someone, I don’t know who, recommended holding the rifle tight to the shoulder. He said the Giss contra-recoil system does not like to be rested directly on a bag. Maybe that was a comment to the Diana 10/Beeman 900 pistol that I tested awhile back. Either way, today I rested the forearm on the flat palm of my off hand that was resting on the sandbag. I did not grip the forearm with my fingers. I also pulled the butt firmly into my shoulder and my right hand gripped the pistol grip of the stock firmly.

Follow-through

Another person said my groups last time looked like I wasn’t following through. I had to agree with him. I made a concerted effort to follow through on every shot this time.

Glasses

Instead of the 1.25-diopter reading glasses that I would normally use, I wore my regular glasses today. My vision is 20-25, corrected to 20-20 by my glasses. The front sight diopter was clear and I was able to center the bull precisely.

Okay, that’s a lot of stuff done differently than last time. Last time the rifle was rested directly on the sandbag, the targets were not taped, I wore the reading glasses and I held the rifle in a classic artillery hold. I also agreed that I was probably not following through on every shot last time. So all the important stuff was changed today to conform to the comments made by you readers.

First group — H&N Finale Match Light

In the last test I thought that H&N Finale Match Light pellets did the best. When I measured the groups I discovered that a different pellet beat them, but I still had a very good feeling about this pellet. The best group with Finale Match Light last time was five in 0.186-inches between centers.

Today I put five Finale Match Light pellets into 0.14-inches between centers. That is a gold dollar group, because it’s smaller than 0.15-inches between centers. It’s also the best group of the day — or at least the best group that I will show you.

The Diana 75 put five H&N Finale Match Light pellets into a 0.14-inch group at 10 meters.

This group was high, so I adjusted the rear sight down 9 clicks. I can’t hear the clicks when I adjust, but the numbers on the scale tell me what I am doing.

Group two — RWS R10 Match Pistol

The next pellet I tried was the RWS R10 Match Pistol wadcutter. In the last test this pellet did the best, putting five into 0.162-inches at 10 meters. This time it didn’t group as tight, with five in 0.198-inches, but that’s still good enough for the silver trime (groups that are less than 0.20-inches between centers).

The Diana 75 put five RWS R10 Match Pistol pellets into a group that measures 0.198-inches between centers at 10 meters.

A secret

And now I’ll tell you a secret. I didn’t shoot just three groups this time. I shot four! The first group of R10 pellets that I haven’t shown measured a tight 0.121-inches between centers — BUT, there is also a lone shot that hit about a half-inch to the left of the group. I believe on the last target that I am about to show you I might have fired one of the five shots at the wrong bull and it was the flier I just mentioned with this first R10 group. I believe that, but I’m not sure.

I looked at the small R10 group through the spotting scope after completing it and I didn’t see a hole off to its left, but when I collected the target there it was. And, on the next group you are about to see, I can only see what appear to be four holes. Also, the wild shot on the R10 bull would have grouped with the rest of these other pellets, had it been shot at the correct bull.

I’m not showing you that smaller R10 group because I don’t know for sure what happened. But I saw the small group clearly through the scope and I believe I would have also seen the stray hole if it had been there. Hey, guys — this is what happens in the real-world!

Head sizes and groups

Jerry Cupples and I had talked for a long time the day before about Pelletgage and I had pellet head sizes on my mind. I just bought 6,500 Vogel target pellets that came in a bulk pack. They can be any head size and I suspected this Diana 75 likes the larger sizes. So I checked the head sizes of both the Finale Match Light pellets and the R10 Match Pistol pellets. I didn’t sort them by head size — I only wanted to know what their general head sizes were in the tin, since they were the two most accurate pellets in this rifle.

Finale Match Light pellets had head sizes that ranged from 4.525 to 4.53mm and R10 Match Pistol pellet heads ranged from 4.515 to 4.525mm. I’m using a special Pelletgage that Jerry produced that goes down to the thousandth of a millimeter.

Then I hand-sorted 11 Vogle pellets with head sizes greater than 4.53mm. I know that is a larger head size than the other two pellets, but at the time I thought bigger was better in this rifle.

Group three — Vogle Match pellets

This group, which may only be 4 shots (it was backed by aluminum tape), measures 0.547-inches between centers at 10 meters. Clearly, and in comparison with the other two (or possibly three) groups, the Vogle is not the right pellet for the Diana 75 — at least not Vogels with heads larger than 4.53mm!

Either four or five Vogle pellets made this 0.547-inch group at 10 meters. I think the Diana 75 does not like pellets with a head size larger than 4.53mm, and it may not like Vogel pellets altogether.

Velocity?

Now I will address something several readers mentioned after they read the velocity test in Part Two. They wondered whether the new piston seal that Dave Slade installed in the rifle a few years ago was still breaking in. You may remember that the former owner of the rifle sold it to me knowing that the velocity was slow. Those readers who commented wondered whether the rifle might speed up as that new seal was used.

Well, between Parts 3 and today I have shot the rifle another 60 times since the velocity test was done. If there is some break-in happening we should start seeing it by now, I think. So I shot another string of 10 RWS R10 Match Pistol pellets for velocity.

The average for this pellet in Part 2 was 534 f.p.s. The low was 526 and the high was 543 f.p.s., so the spread was 17 f.p.s.

Today I oiled the piston seal with two drops of silicone chamber oil, then fired 9 shots to settle down the powerplant. When oil stopped spraying out on every shot, I started the chronograph. The average today was 545 f.p.s and the spread went from a low of 539 to a high of 551 f.p.s. — a difference of 12 f.p.s. After 60 shots since the last velocity test the average velocity for this pellet is up by 11 f.p.s. and the spread is down by 5 f.p.s. It’s a small difference but it does appear that the new piston seal could be breaking in. I plan to watch the velocity of this rifle over time and see how it develops.

Why?

Why did I run this extra accuracy and velocity test? I did it because in the future I want to pit this rifle against my FWB 300S that is the most accurate 10-meter rifle I own. I learned a lot today, and I have explained all of it to you in this report.

This rifle came to me with a test target group that measures 0.065-inches between centers. As far as I’m concerned, we have not yet seen performance of that level from this rifle. That means one of two things, or both. Either I haven’t yet found the right pellet for the rifle, or I haven’t yet found the right head size. I think the ideal head size for this rifle is around 4.52mm. Based on the smallest group of R10 pellets that I didn’t show you, the group that might measure 0.121-inches between centers if I’m right about the flier, the R10 may be the best pellet and 4.52mm may be the correct head size.

The test target that came with the Diana 75 is serial-numbered to the rifle. A group of five pellets are in 0.065-inches at 10 meters.

Another accuracy test

I see another accuracy test is in store for this rifle. I want it to do its very best when it faces my FWB 300S, because that rifle certainly will be doing the same.

Lookalike airguns: Part One

Posted on February 26, 2021 by B.B. Pelletier ↓ 51 Comments

by Tom Gaylord
Writing as B.B. Pelletier

History of airguns

This report covers:

What is a lookalike?
A typical lookalike
Colt held back
They got better
Military or civilian?
I could go on

Today we begin a series on lookalike airguns. I don’t know exactly how long this could be, but I suspect it could be large. I also know that this subject is a favorite for many of you.

What is a lookalike?

A lookalike airgun is one that resembles an iconic firearm. It gives the owner the chance to experience the feeling of ownership and operation while remaining in the safer, less litigious world of airguns.

A typical lookalike

In a moment I will discuss the difference between a military lookalike and a purely civilian one, but let’s begin with a look at a gun that exists in both camps — the iconic Colt Single Action Army revolver! The SAA, as it is called, was brought out by Colt as the next step in revolvers from their famous black powder cap and ball handguns. While it wasn’t the last in the line, the Colt 1860 Army is perhaps the best example of an evolved single-action cap and ball revolver. It certainly is the best example of a Colt revolver from that time.

Colt’s 1860 Army revolver was highly advanced for a cap and ball black powder handgun.

When Smith & Wesson patented the revolver cylinder that was through-bored (open all the way through the cylinder) in the 1850s, they allowed the use of cartridge ammunition for the first time. Their first firearm on that patent was the model 1 that was initially chambered for .22 rimfire. It came to market in 1857 — just in time for the American Civil War. The cartridge it was chambered for was just called a .22 rimfire, but as that cartridge line evolved in the latter 1800s, it became known as the .22 short.

Smith & Wesson’s model 1 came out in 1857 and lasted until 1882. It was chambered for what we now call the .22 short cartridge.

The model 1 was very popular as a backup gun by Northern troops in the Civil War. It didn’t have much power — perhaps 25 foot-pounds or so, but it was better than nothing.

Colt held back

The bored-through cylinder was patented by a former Colt employee, Rollin White. Why he didn’t try to sell the idea to Colt first we may never know, and maybe he did. Smith & Wesson pounced on it and paid White a royalty of 25 cents per gun, which was a huge sum for the day. But they also agreed he would defend the patent and doing that eventually ruined him, financially.

Colt couldn’t make cartridge revolvers as a result of the S&W patent, so they made variations on their 1860 model until the patent on the bored-through cylinder ran out in 1872. Then they brought out their ubiquitous 1873 SAA that is still in production by many manufacturers today.

Colt Single Action Army. This one was a gift to BB from the readers of this blog, following his 3.5-month hospital stay in 2010. It was not made by Colt, but it is a very accurate copy of that firearm and is chambered in .45 Colt. Reader Kevin was the focal point for this gift!

If you grew up in the 1950s and the early ’60s like BB, you watched westerns on television. Two of my cats were named Roy Rogers and Dale Evans, after two western stars of the time. Their real names were Leonard Franklin Slye and Frances Octavia Smith.

I idolized all things cowboy and so when Crosman brought out the .22-caliber SA-6 (single action six) pellet revolver in 1959, I bought one with my paper route money.

Crosman-SA-6.

I didn’t have a holster for that revolver and, since holsters cost money, I carried the SA-6 in my right front pants pocket — a practice that was common in my day and also one that I do not recommend. I loved that .22 caliber pellet pistol. One day while “hunting” in the woods around the Cuyahoga River in Stow, Ohio, a rabbit jumped out of the weeds and frightened me. When my “cool” returned several seconds later I calmly drew my pellet pistol and fanned off 6 quick shots into the weeds where the rabbit had gone 5 seconds before, earning the nickname, “Fanner 50” from my friend who was with me. For readers less than 60 years old, a Fanner 50 was a very popular cap gun of the day.

They got better

So the SA-6 was an early attempt at a lookalike SAA. The CO2 cartridge hid beneath the barrel, covered by a black plastic sheath that camouflaged it very well. But things would get better.

In the late 1990s I was at the home of Wulf Pflaumer’s sister in Maryland. Wulf is one of the two founders of Umarex. We were discussing the lever action rifle he was about to bring out and I told him that a realistic SAA would also be a hit. He told me they wanted to make one but the revolver’s grip frame was too short to allow a 12-gram CO2 cartridge to fit inside. I told him to try the Colt 1860 Army grip frame. It is 1/2-inch longer and the outlaw, Dakota, at Frontier Village amusement park where I worked in college had put one on his SAA because the SAA grip was too short for him. The 1860 grip frame fit a 12-gram cartridge perfectly and almost no one notices the difference. The rest is history.

A couple years later Umarex brought out the Colt SAA in both pellet and BB gun versions and they have now produced almost every variation of that firearm except for some reason the 4-3/4-inch barrel version that many shooters have asked for. Bat Masterson carried a 4-3/4-inch SAA, as did many gunfighters, because it cleared the holster quicker and was therefore faster to draw.

The first Umarex SAA was very realistic, as have been all that followed.

Military or civilian?

I said I would return to this topic. The Colt SAA we have been discussing is both. It was first purchased by the military, but civilian sales soon surged past what the military bought. The SAA is so ergonomic that, until the German P08 Luger pistol came around, it was the long pole in the tent. And it’s still one of the most desired, and most recognized handguns of all time.

There are things about military firearms that make them attractive to shooters. Strength, design and robustness are all main factors, but history trumps everything. No one who has ever held and fired an M1 Garand would think of it as an attractive weapon, but Japan, who was an enemy of the US during WW II, thought enough of it to create 250 close copies for study. Called the Type 4 rifle (and sometimes the type 5), it was homage to the American rifle that so dominated our military campaigns in the latter half of the war.

That addresses why we have military lookalike airguns, though I probably have more than one more report to do on just them, but what about civilian firearm lookalikes? Are there any of them? There certainly are. I won’t get into them deeply this late in today’s report, but for starters, don’t forget the Crosman 38C and 38T revolvers.

And this I will also say, though I call them civilian firearms, the military buys oneseys and twoseys of just about anything. Just because Sergeant So-And-So carried one on the flight line at Da Nang doesn’t make it a military firearm. I’m talking about firearms the military officially adopted — not something Private Ryan carried in his combat boot.

Crosman’s 38-T from the 1970s was a replica of S&W’s purely civilian (and law enforcement) revolvers.

I could go on

And I plan to. The world of airgun lookalike/replica guns is both a hot topic at any time and red-hot today. Even though this report is in the history section, we are still living in the heyday of lookalike airguns.

Mondial Oklahoma spring-piston pistol: Part 2

Posted on February 19, 2021 by B.B. Pelletier ↓ 77 Comments

by Tom Gaylord
Writing as B.B. Pelletier

The Mondial Oklahoma pistol.

Part 1

History of airguns

This report covers:

Further tie-ins to the Roger CO2 pistol
Choose one
Performance
RWS Hobby
Air Arms Falcons
RWS R10 Match Pistol
Loose breech
Discharge sound
Accuracy?
Summary

Today I test the velocity of the Mondial Oklahoma air pistol we have started looking at. I was hoping so much that another owner would comment that he had a pistol with a rifled barrel because this one is smoothbore for sure. But no one has come forward yet. And no, the rifling hasn’t worn out of this one. This is a breakbarrel spring-piston air pistol that was made to sell at a low price, but as I noted in Part One, a lot of thought went into its design.

Further tie-ins to the Roger CO2 pistol

Reader Pacoinohio asked for more information about the tie-in between the Oklahoma and the Daisy 100. I have information that comes from two different sources and goes in two different directions. First, while researching Mondial I learned that they also made the Roger CO2 pistol that looks something like the Daisy 100. Many years ago an advanced Daisy collector at an airgun show showed me his Roger pistol in the box that he felt was extremely rare. He also told me that Daisy bought the plans for the Roger and that was what the Daisy 100 was based on. They are not exactly the same and I doubt that many parts interchange, if any, but any designer finds his work easier if he has something to go on. I think that was essentially what happened, if any of it is true.

The other direction I will come from is that I wrote the largest report that has ever been written on the .22 rimfire firearms made by the Wamo corporation. It was published in one of the Airgun Revue magazines. This company is known as Wham-O today and we know them for their Hula Hoops, Superballs and Frisbees. But Wamo also made at least three different .22 rimfire guns, though they claim they never did. The most popular one they made was called the Wamo Powermaster. It was a .22 long rifle single shot that ejected the empty cartridge case and the bolt remained back for loading.

Years ago Dennis Quackenbush, who many of you know as the builder of big bore airguns, told me that he can convert the Daisy 100 into a Powermaster. Yesterday morning Dennis told me that to him it appears that Daisy purchased the Powermaster design and tooling from Wamo and turned it into their model 100 CO2 pistol. That’s why Dennis says it is so easy to turn a 100 into a Powermaster. He says that because he sees little design details in the Daisy 100 that come from the Powermaster and are unnecessary for the air pistol, so it looks to him like Daisy used the Wamo tooling to make their airgun.

Here are the Wamo Powermaster (top) and Daisy 100 for comparison. Photo courtesy Dennis Quackenbush.

And here is a Roger. I have to say, it doesn’t look much like the Daisy.

Choose one

That’s two different stories of the relationship between the Daisy 100, the Wamo Powermaster and the Roger air pistol. You decide. I’ve told you all that I know.

Performance

So, how does the pistol I am testing perform? According to the Blue Book of Airguns I should expect about 200 f.p.s. I oiled the piston seal and the breech seal days before this test so this one will do as well as it possibly can. Let’s see.

RWS Hobby

First to be tested was the RWS Hobby wadcutter. They fit the breech very tight and wouldn’t even sit flush.

That’s as deep as the RWS Hobby would go into the Oklahoma breech with finger pressure.

I knew when I saw how tight Hobbys were that they needed to be seated deep, so the head and skirt would be sized down by the barrel. Just for fun I shot one Hobby seated like you see in the picture. It went out at 175 f.p.s. Ten more when seated deep with a ballpoint pen averaged 244 f.p.s. That’s a gain of 69 f.p.s. from just deep seating. The low for the string was 231. The high was 253, so the difference was 22 f.p.s.

I’m guessing other pellets that are light but not so large as Hobbys will be faster. Let’s see.

Air Arms Falcons

At 7.33-grains the Falcons are heavier than the Hobbys, but they are also smaller, so there is less resistance. I deep-seated them, too.

Falcons averaged 236 f.p.s. over 10 shots. The velocity ranged from a low of 223 to a high of 246, so a 22 f.p.s. spread. Let’s try one more pellet.

RWS R10 Match Pistol

The RWS R10 Match Pistol pellet weighs 7 grains like the Hobby, but it fits the breech almost as well as the Falcon. It’s just a little tighter. Ten of them averaged 254 f.p.s. in this Oklahoma. The low was 251 and the high was 257, so the spread was 6 f.p.s. That’s not only very good, it’s also considerably faster than the Blue Book said, so I assume this pistol is performing well.

Loose breech

I noticed while shooting that the breech on the pistol is loose. However, it is the strangest loose breech I have ever seen. It’s loose when the pistol is cocked but not when it isn’t, which means when the piston is forward it’s somehow affecting the tightness of the breech.

Discharge sound

I tested the sound at discharge with the audiometer app on my smart phone. It’s very quiet when it fires.

Accuracy?

I don’t have very high hopes for this pistol to be accurate. The inexpensive construction plus the smooth barrel are two reasons why.

I think I will start my accuracy test at 20 feet, rather than 10 meters. And I will look for pellets that fit the breech loosely, or at least not overly tight. I really have no idea of what to expect with this one, but I’m not getting my hopes up.

Summary

The Oklahoma air pistol is an airgun I have long wanted to examine and test. Now I’m getting to. I hope you are finding this as fascinating as I am.

Diana 75/Beeman 400 recoilless target air rifle: Part 3

Posted on February 12, 2021 by B.B. Pelletier ↓ 86 Comments

by Tom Gaylord
Writing as B.B. Pelletier

The Diana 75.

Let’s make lemonade
Part 1
Part 2

History of airguns

This report covers:

The sights
No clear inserts
The test
Sight in
RWS Meisterkugeln Rifle
RWS R10 Match Pistol
Vogel Match
Discussion
H&N Finale Match Heavy
H&N Finale Match Light
RWS R10 Match Heavy
Something more
Discussion 2
Summary

Today we start testing the accuracy of the Diana 75/Beeman 400 target air rifle.

The sights

I first had to mount the rear sight and change the front sight post insert for an aperture. The Diana rear sight is straightforward, except this one has adjustment directions in English rather than German. You simply adjust the knob in the direction you want the pellet to move. Simple! I had the rear sight on the rifle, positioned and clamped tight in about 15 seconds. But the front sight…!

The Diana 75 rear sight is conventional except the adjustment markings are English and not German.

The front sight, on the other hand, is a real piece of work! I didn’t pay much attention to it until this morning, just before I shot the rifle. I knew I needed to switch inserts because it had a tapered post and I wanted an aperture. Wayne Johnson who sold me the rifle sent all the sight inserts in a small jar, along with some other stuff that I need time to research.

There’s a whole lotta magic inside this Diana 75 front sight.

The conventional sight inserts.

… and there was also this stuff. I think it’s an adjustable front sight aperture, but I need time to research it. The red tube appears to be a wrench for the sight.

No clear inserts

I had hoped to install a clear plastic front sight aperture today, but the ones I have don’t fit. At least I wasn’t able to get them to fit. So I used a 3.5mm steel aperture insert from the ones shown above. It works well so far.

The test

Today I’m just getting used to this new target rifle and finding out what sort of pellets it likes. I shot from a rest at 10 meters with the rifle rested directly on a sandbag. I shot 5 shots per group.

Sight-in

There was no sight-in! Perhaps for the second time in more than a half century of shooting, the sights were on target from the get-go. That’s odd because I store this rifle in a case with the rear sight removed and today I also swapped the front sight insert. I felt lucky to just be on paper at 10 meters, and never expected to hit in the bull I aimed at! The pellet was not perfectly centered but since I’m testing a lot of different pellets I left the sights set where they were.

RWS Meisterkugeln Rifle

I chose RWS Meisterkugeln Rifle pellets to sight in for no particular reason. When the first pellet landed in the black I decided to just finish the first group. Unfortunately it isn’t very small. Five pellets made a group that measures 0.526-inches between centers. Ugh!

The Diana 75 put 5 RWS Meisterkugeln Rifle pellets in 0.526-inches at 10 meters. It is the largest group of the test. This group isn’t as big as it looks because there was some tearing of the target paper.

RWS R10 Match Pistol

The second pellet I tested was the RWS R10 Match Pistol wadcutter. Five of them went into 0.162-inches at 10 meters.

That’s the stuff! Five R10 Match Pistol pellets went into 0.162-inches at 10 meters.

When I shot this group I wasn’t aware how small it is because of some paper tearing. This is the smallest group of today’s test.

Vogel Match

This was the pellet I hoped would do best because I just ordered 5,000 of them on a bulk buy at a fabulous low price. They come in different head sizes and the ones I tested today are nominally 4.50mm. But, yucky-poo, they grouped in 0.403-inches between centers! And paper tearing makes the group look larger than it is. These pellets weigh 8.3-grains nominally.

Five Vogel pellets with 4.50mm heads made two groups that measure 0.403-inches between centers.

Discussion

Okay — I’m startin’ to figure this out. The heavy pellets are moving so slow that they are tearing the paper. I probably need to visit Neal Stepp to get this rifle put right again. And heavy pellets aren’t as accurate as the light ones.

Also I want to report that the 75 doesn’t come back at me when it fires, so I can put the rubber eye shield against my glasses for every shot. That’s a reminder to myself for next time. Let’s shoot some more.

H&N Finale Match Heavy

The next pellet I tried was the H&N Finale Match Heavy wadcutter. I still didn’t know about the rifle’s aversion to heavy pellets. Five of these made a group that measures 0.259-inches between centers. That’s not too bad except the Diana 75 is a target rifle that should put them into a group of half that size.

The Diana 75 put five H&N Finale Match Heavy pellets in 0.259-inches at 10 meters.

H&N Finale Match Light

The next pellet I tested was the H&N Finale Match Light. Given how well the Heavys did I expected this pellet to do well and it did. After I saw the group I thought this was the smallest group of the test, though after measuring I discovered it wasn’t. Five pellets are in 0.186-inches at 10 meters. Another trime!

The Diana 75 put five H&N Finale Match Light pellets in 0.186-inches at 10 meters. It’s good enough for another trime!

RWS R10 Match Heavy

Next up were five RWS R10 Match Heavy pellets. Care to guess how they did? Given what we now know it was no surprise that five of them went into a group that measures 0.329-inches between centers.

Five R10 Heavy pellets made this 0.329-inch group at 10 meters.

Something more

At this point I had not measured the groups and I thought that the H&N Finale Match Light pellets were the most accurate. So I adjusted the rear sight for them. When I did I discovered that I can’t hear or feel the clicks on this target sight, so I have to watch the numbers on the knobs. It’s the only way to know that you’ve made an adjustment. Based on where the first group landed I moved the rear sight up and to the right.

The second group I shot with the H&N Finale Match Light pellets measures 0.351-inches between centers. I had hoped to do a lot better than that, so maybe I was starting to get tired. The group was higher than the last but still needed to go right.

The second group of Finale Light pellets measures 0.351-inches between centers.

I adjusted the sight a little more to the right for the next group. It already seemed high enough.

For the third and final group of Finale Match Light pellets I pulled out all the stops and concentrated as hard as I could. This time five pellets made a 0.272-inch group. It’s very horizontal and I realized I had come to the end of my test for this day.

The final group of Finale Match Light pellets is five in 0.272-inches at 10 meters.

Discussion 2

Well I didn’t do as well as I had hoped. Certainly at this point my FWB 300S is more accurate in my hands than this Diana 75. But the Diana is more pleasant to shoot because the action doesn’t move when it fires. It doesn’t come back into my glasses.

At this juncture I am pondering what comes next. Do I continue to shoot this rifle, try different pellets and see if I can do better, or do I get it back to speed, so to speak? I think most of you will want me to get it looked at.

It probably isn’t fair to put it up against my FWB when it’s not performing as it should. The FWB 300S has already shot several groups smaller than one-tenth-inch and it gets an average 658 f.p.s. with the R10 Pistol pellet, where this Diana only gets an average 543 f.p.s. at the present.

Summary

I still need to learn about that strange front sight setup that appears to be an adjustable-diameter aperture. I kinda want to hang onto the rifle long enough to write that up.

But not to worry — you’re going to see this Diana 75/Beeman 400 many more times in the future!

Mondial Oklahoma spring-piston pistol: Part 1

Posted on February 8, 2021 by B.B. Pelletier ↓ 49 Comments

by Tom Gaylord
Writing as B.B. Pelletier

The Mondial Oklahoma pistol.

History of airguns

This report covers:

Blue Book got it wrong
Several models
Two finishes
Many are boxed
Strange construction
Breakbarrel
Soda straw barrel
Breech seal
Markings
Sights
Summary

Today we begin looking at a strange air pistol that has a lot of interesting quirks. Do you readers like interesting quirks? Ha! Does an elephant like peanuts? This is the Oklahoma from Mondial. Mondial is the trade name of Italian manufacturer Modesto Molgora of Milan.

Blue Book got it wrong

First I note that the Blue Book of Airguns lists this pistol as having a rifled barrel. Well, the one I am testing certainly doesn’t. One of two thing are possible. Either the smoothbore I have is a variation that the Blue Book is not currently aware of or they got it completely wrong and all Oklahoma pistols are smoothbore. If you own an Oklahoma pistol would you please examine the bore to see whether it is rifled?

I went online to research this pistol and found very little information. Most listings mention the rifled barrel in such a way that they seem to have copied what’s in the Blue Book or some other reference. I see that a lot online. Why would anybody mention a rifled barrel, when a smoothbore would be the exception? Yes, there are many smoothbore airguns but why go to the trouble of mentioning a rifled barrel when most airguns have them?

John Walter’s books that are four editions titled, The Airgun Book, aren’t really certain whether the barrel is rifled or not. There is a question mark after the number of lands and the rifling direction in one of the editions. So they don’t know. But BB knows. This one isn’t rifled.

Several models

Mondial made several air pistols besides the Oklahoma we are examining today. One was called the Oklahoma N.T. That one has a hooded front sight, though the rear sight is fixed, so the hood really adds nothing. Another is called the ZIP and it has an adjustable rear sight located back on the rear of the spring tube. And one more pistol is the CO2-powered Roger that was the foundation for the Daisy model 100 pistol that later became the Wamo Powermaster .22 rimfire pistol.

Mondial also made a couple breakbarrel rifles, the Carabina and the York. They also made an underlever BB repeater they called the Condor.

Two finishes

I have found two different finishes for the Oklahoma — blued and nickel. Many would call it chrome, but chrome is very rare on an airgun or a firearm. Nickel is more durable than most chrome-plating, making it the general plating metal of choice for firearms and airguns. Unless you have the two materials side-by-side it’s difficult to differentiate, but when held next to chrome you will see that nickel plating has a slight golden cast, while chrome is just silver.

The pistol I bought to test is nickel-plated and has no box, because I got it from a generous friend of this blog who sold it to me for a very good price. The grip panels are reddish-brown plastic and are held to the gun with two screws that pass through the gun and have hex nuts inset into the right grip panel. I have more to say about that in a moment.

The grip screws are held in by a nut on the right side. It doesn’t look like a hex nut in this photo…

…so I pushed it out to see it better.

Many are boxed

When I looked for a pistol to test for you, most of the ones I saw were offered in the box. According to the printing on the box (and my best version of Google translate for Italian) they came with both pellets and BBs, which underscores the smooth bore. One I found on eBay had an original price sticker on the box marked $7.95. The Blue Book puts the start of this pistol sometime in the 1960s but gives a definite end date of 1988. The John Walters Airgun books agree with the start time and give no ending date.

Strange construction

The pistol is made from two non-ferrous metal frame pieces that are held together by screws and hex nuts all around the frame. Besides the two in the grips I count another four, for a total of six. If they were all removed it appears the pistol would come apart. And there would be pieces held on pins inside and BB Pelletier would scatter them around, so don’t ask!

Oklahoma frame nut
The entire pistol is held together with screws and nuts like this.

Breakbarrel

The Oklahoma is a breakbarrel with a spring-loaded barrel lock. Push it back to release the barrel for cocking.

That lever hanging down is a spring-loaded barrel lock.

Push the lock back and the barrel is released for cocking.

Soda straw barrel

The barrel is a thin tube that we call a “soda straw” barrel. These are usually rifled barrels, but as I said, this one is a smoothbore. It must have been cheaper to make it this way, because the barrel looks to be pressed into a solid outer jacket.

The actual barrel is a thin tube inside an outer jacket. Neither the tube nor the jacket is ferrous.

Breech seal

The breech seal is located on the end of the frame rather than around the breech, where there is no room. It appears to be made of some rubbery synthetic that is still in good condition after no less than 33 years and possibly more than 50.

The breech seal is in the frame.

Markings

The maker’s name and logo are on the right side of the frame, along with Made In Italy and Olio, around the oil hole.

Yep — it was made in Italy all right!

The name of the pistol and the caliber are on the left side.

Sights

The sights are fixed and both the front and rear sight are attached to the barrel. Given the thickness of the breech seal, it seems the makers were concerned about barrel alignment issues. That plus the barrel lock tells me that the designers of this airgun really cared about making a quality product. It may have been inexpensive but in no way was it cheap. Somebody was doing their best within an envelope of cost constraints. Which makes the smoothbore barrel all the more strange.

Guys — I’m telling you all that I know and all that I have been able to find out about this quirky air pistol. Given the huge reach of this blog I am hoping someone can add a few more things to further our knowledge. I would especially like to know whether there really is an Oklahoma like this one that has a rifled barrel.

Summary

I’ve been a serious airgunner (as in paying attention to what is going on, over and above just shooting and enjoying the guns) since starting The Airgun Letter in 1994. Since then I have seen Oklahoma pistols at several airgun shows but never have I taken the plunge. I did it now just to expand my horizons, as well as yours.

There isn’t very much written about this air pistol — at least not in the English language. Much of what is written seems to be guesswork, though Walter’s books do have some solid facts about the companies involved and the models of the guns. This one should be interesting.

Diana 75/Beeman 400 recoilless target air rifle: Part 2

Posted on February 5, 2021 by B.B. Pelletier ↓ 89 Comments

by Tom Gaylord
Writing as B.B. Pelletier

The Diana 75.

Let’s make lemonade
Part 1

History of airguns

This report covers:

Recoil
Velocity test
R10 Pistol
H&N Finale Match Light
JSB Match Diabolo
Discharge noise
Discussion
Cocking effort
Trigger pull
Summary

We will take a second look at the Diana model 75 sidelever recoilless target rifle that we have learned was sold as a Beeman model 400. You saw the sales receipt in Part 1 that clearly identifies this as a Beeman 400.

Today we will look at a few more things on the rifle and we will test the velocity. As many of you covet one of these old target rifles of the past, this should be an interesting report.

Recoil

The first thing I will address is recoil, or in the case of this rifle, the lack of it. The Diana 75 was made at a time when a recoilless spring-piston air rifle was the height of technology. There were several ways to do it.

Feinwerkbau used a system of thin steel rails inlet into the stock of their 300-series target rifles that allowed the big heavy barreled action to slide one way when the pellet shot out the other. As long as the rifle is held fairly level this system works well, and a target shooter is always going to hold the rifle fairly level. The only thing the shooter feels is the rubber eye cup coming back into his shooting glasses, as the entire barreled action moves rearward by a fraction of an inch.

Anschütz used an oil-filled damping mechanism in their model 250 target rifle to counter the forward movement of the piston. It was subject to leaks and the most problematic of all the anti-recoil systems.

Weihrauch used a combination of weight and stock configuration, plus a smooth tune to counter recoil in their HW55 Custom Match that was the high-water mark of their spring-piston target rifles. The rifle weighs two pounds less than an FWB 300S, but a hollow forearm allows for the insertion of more than two pounds of lead weight.

An HW 55 won the gold medal at the European Championship in 1969. Like the proverbial tale of the last buggy-whip maker that made the finest buggy whips ever created, the HW 55 CM was the finest spring-piston 10-meter target air rifle Weihrauch ever produced. When the Custom Match hit the market in the 1970s, it came just after the summit of success. Little did they know at that time that there would be no more major championships for recoiling air rifles of any make. It was similar to the last gasp of the Offenhauser front-engine Indy cars when Ford got into Indy racing in 1963.

The HW55 CM was not a true recoilless spring-piston rifle, though when weighted and tuned correctly it came close. It reminded me very much of another recoiling target rifle that was nearly recoilless — the FWB 110! Instead of giving you a paragraph on that one I have linked to a special two-part report of the rarest airgun I have ever tested. That report says all I know about that rifle.

And I cannot overlook the Walther LGV. Like the HW55 CM, it is another recoiling target rifle that uses weight and a fine tune to cancel as much as possible. It also has a hollow forearm that allows the insertion of lead, and the ones I have examined have all had the lead poured in in its molten state so that all the space was taken.

And now the Diana 75. It has a Giss double counter-recoiling piston in which the rear piston cancels the movement of the front piston that has the seal to compress the air. John Whiscombe used a variation of this system where both pistons come together like the clapping of hands and instead of 6 foot-pounds that we see in target rifles they can generate as much as 30+ foot-pounds!

When an airgun with a Giss system like this Diana 75 fires there is no movement. All that is felt is a slight impulse through the stock or through the grips if it’s a pistol. This means that the target shooter can press his eye firmly against the rubber eyecup on the rear sight and feel nothing. Compared to the FWB 300 sight that comes back at you, I like this one better.

Velocity test

Remember that Wayne Johnson who sold me the rifle had chronographed it before listing it on Gun Broker and found it was shooting slow. It had been tuned by Dave Slade several years earlier and Wayne didn’t chronograph it when he got it back. He mentioned that fact prominently in his Gun Broker listing which is probably why no one had bid when I contacted him. When I approached him I acknowledged that I understood it was shooting slow, and he was happy to make a deal with me. So, I’m expecting the rifle to be a bit slow today.

R10 Pistol

The first pellet I’ll test is the 7-grain RWS R10 Match Pistol pellet. Ten of them average 534 f.p.s. The low was 526 and the high was 543, so the spread was 17 f.p.s. That is a high spread and the velocity is slow for a Diana 75 with a 7-grain pellet, but it’s fast enough for an accuracy test. I don’t know if I will have the gun checked out or not yet. It depends on what I see with accuracy. I’m thinking I will leave it alone.

H&N Finale Match Light

The next pellet I tested was the 7.87-grain H&N Finale Match Light. Ten of them averaged 505 f.p.s. The low was 494 and the high was 509 f.p.s., so the spread for this pellet was 15 f.p.s.

JSB Match Diabolo

The last pellet I tested was the 8.3-grain JSB S100 Match Diabolo target pellet. Being the heaviest they were expected to shoot the slowest, which they did. Ten averaged 500 f.p.s. the spread went from a low of 489 to a high of 506 — a difference of 17 f.p.s.

Discharge noise

The 75 is quiet, like you would expect. There is no silencer, but the low power and long barrel play their part. Discharge sound recorded at 92.5 decibels.

Diana 75 discharge

Discussion

This Diana 75 is a little slow and the spread is higher than I would like to see. But at 10 meters that probably won’t mean very much. You saw the 5-shot test target thast came with the rifle in Part One. That group measures 0.065-inches between centers. I doubt I can do as well, but let’s see what I can do. I plan to shoot a lot of different pellets in the accuracy test because this rifle is going in my estate!

Cocking effort

The sidelever cocks the rifle with 15 lbs. of effort as it retracts the sliding compression chamber, pushing back the piston. There is a fine ratchet in the cocking linkage, so if you let go of the sidelever it will stop instantly wherever it is. It will not return to the closed position until the rifle is cocked.

When the sliding compression chamber is all the way open you can see the blue seal that mates with the rear of the barrel. This material is what Diana now uses for their piston seals and some breech seals and it should be a lifetime material.

This is the Diana 75 breech seal. I know it looks pink or magenta or some other color that doesn’t really exist, but it’s blue. Photoshop fought with me a long time with this! Remember — old BB is red/green colorblind! At any rate, it isn’t light brown and crumbling because Dave Slade replaced it.

Trigger pull

The two-stage trigger is set for a 3-ounce pull on stage one and it breaks at 7 ounces. It is as light as I want it to be.

Summary

In short, I like this Diana 75/Beeman 400 a lot! I believe I promised a shootout between this rifle and my FWB 300S that is currently the accuracy leaders at Casa Pelletier. If I didn’t I’m doing it now. The Feinwerkbau is extremely accurate, having put five pellets into a 0.078-inch group at 10 meters, so this rifle has some stiff competition ahead.

Diana 75/Beeman 400 recoilless target air rifle: Part 1

Posted on January 18, 2021 by B.B. Pelletier ↓ 41 Comments

by Tom Gaylord
Writing as B.B. Pelletier

The Diana 75.

Let’s make lemonade

History of airguns

This report covers:

Refresh your memory
Wayne Johnson
The Diana 75/Beeman 400
Right-hand bias
History of the Diana 75
Giss contra-recoil mechanism
Sights
The wood
The metal
Summary

Today we begin our look at the Beeman 400 sidelever recoilless target air rifle that is really a Diana 75. I linked to the Making lemonade report because of the piston seals. That should be an issue I no longer need to explain.

Refresh your memory

This air rifle is the one I saw on Gun Broker and contacted Wayne Johnson, the seller, directly. I offered what I felt was a good price, plus the shipping he requested. I had never done that before and I was called a name for doing it, but I felt this was a special airgun and Wayne was a special owner. Here is exactly what I said to him on my first contact.

Diana 75 contact remarks

Wayne Johnson

Wayne and I hit it off right away. I would normally never publish the full name of anyone in this blog, unless that person was a personality or they were out there for some other reason. Wayne is the author of The FN49, The Last Elegant Old-World Military Rifle, expanded second edition, copyright 2019 by Wayne Johnson, published by Wet Dog Publications.

Diana 75 book
Wayne’s book is an excellent treatise on the development, production and oddities of the FN49 battle rifle.

I bought his book because the FN49 is a military rifle I always wanted to know more about. Now I do, thanks to Wayne.

Wayne is the kind of person you want to buy something from. From his listing I could tell that he is scrupulously honest, because on Gun Broker he listed every fault the rifle had — not that there were many! And, after he accepted my offer we conversed a little about his airgun.

Hi Tom,
I don’t think I need the proof of age – I imagine you are over 18 !

Yeah – I am pretty much a straight arrow on the auction stuff and no, I’m not insulted by the direct approach. After I had the gun serviced by David Slade I should have chronographed it to see what it did with the new seals. I was VERY disappointed when I test fired it yesterday and realized that it was shooting slow so I wanted to make sure that I pointed that out in the auction. Anyway, as I mentioned before, I made this exception on cancelling the auction since I know it’s going to the right place. I did have 45 views on that auction in the first 12 hours along with 4 watchers so no telling where the auction might have gone but regardless, I like where the rifle is going.

I’ve attached to this email a scan of the original receipt that shows the purchase price from Beeman – I don’t know what info you include in your air gun write-ups but that may be of interest to some readers. I’ll include in the papers for the gun my original chrono data from 1984, when the gun was two years old (with 1500-1600 pellets fired) that shows it averaged 605 fps on two different range sessions.

If you think of it, after you complete and post your review of this rifle perhaps you could send me a link to that article.

Best,
Wayne

First off, know that I emailed Wayne the link to this blog. This is something I have been wanting to do ever since I got the rifle.

I want today to be about the Diana 75 target rifle in general, but I will weave in things that are special about this particular rifle as I go. Just getting ready to take pictures last Thursday I discovered an “Easter Egg” gift that Wayne had packed under the foam of the hard case he sent the rifle in. It was an unopened tin of Beeman Silver Bear hollowpoint pellets that the note said were about 35 years old. Well, they will still be unopened at my estate sale, so watch for them!

The Diana 75/Beeman 400

Although this rifle was sold to Wayne as a Beeman 400, it is a Diana 75. We sometimes see the name RWS attached to Diana airguns in the U.S., but that is an importation thing. Diana makes the guns. Both Robert Beeman of Beeman Precision Airguns and the late Robert Law of Air Rifle Headquarters thought enough of the 75 to sell it. But Beeman did change at least the name he called it in his catalog, if not the actual markings on the airgun.

Diana-75-receipt

There are no Beeman markings on the rifle.

Beeman literature like this parts list, plus the purchase receipt, is the only way to tie the rifle to Beeman as a 400.

The 75 has a long production life, though it changed and evolved as time passed. The basic 75, which I believe this rifle to be, was produced from 1977 to 1983. Mine was made in March of 1981, according to the date code stamped into the spring tube. Other versions of the rifle lasted until the 1990s.

Diana 75 date code
This 75 was made in March of 1981.

Right-hand bias

My rifle was made for a right-handed shooter. How can I tell? Look at the buttstock and see if you can tell.

Whaddaya think? Made for a righty?

As the years passed, manufactures would move to more adjustable stocks so they weren’t locked into right- or left-handed shooters. But the 75 was made at a time before such things were considered.

By the way, Diana did offer the rifle with left-hand stocks and the Blue Book of Airguns says to SUBTRACT 10 percent for one! That’s odd, because everyone else adds a small percentage for a southpaw stock. Gotta change that in the book next time. I already wrote a note in my bench copy of the Blue Book.

History of the Diana 75

The Diana 75 lies at the end of a long line of recoilless Diana target air rifles that began with the Diana model 60 in 1960. The 60 was a pretty basic breakbarrel target rifle which was okay for a few years, as its competitors were also breakbarrel — like the Weihrauch HW 55 and the Walther LG 55. But when rifles like the sidelever FWB model 110 came out and then quickly morphed into the recoilless model 150, shooters started wondering whether fixed barrels were somehow more potentially accurate since their barrels never moved. That’s a hard argument to ignore and the world moved on, though Diana did bring out two more refined breakbarrel target rifles — the 65 and the 66.

Editor’s note: I cannot locate Part 3, the accuracy test for the FWB 150. I’m pretty sure I did it, but with all the WordPress changes over the years it’s gotten misplaced.

When the 75 came out it represented the high-water mark for Diana spring-piston air rifles. It was a Diana 66 with a fixed barrel and a sidelever for cocking. It was fully capable of competing against the finest FWB 300S, which it did for several years before CO2 and finally PCP rifles pushed springers off the world stage completely.

The test rifle came with its original manual that includes a Diana test target in which five pellets have grouped in 0.065-inches at 10 meters. That will give my most-accurate FWB 300S a run for the money!

The test target that came with the Diana 75 is serial-numbered to the rifle. A group of five pellets are in 0.065-inches at 10 meters.

Giss contra-recoil mechanism

Probably the best-known feature of the 75 is its Giss contra-recoil mechanism that renders it recoilless. As the real piston with its seal moves forward to compress the air, an equally-weighted false piston moves in the opposite direction. Both pistons stop at the same instant, cancelling all felt recoil. This system works surprising well, though it does pose a problem for airgunsmiths.

When replacing the piston seal, which you now know must be done at least once, the rear false piston must be timed perfectly if the contra-recoil is to be maintained. Timing can be a touchy task, and a shooter will notice immediately if it’s off. So, it must be done perfectly. Dave Slade replaced the piston seal in this rifle and I can tell you that he nailed it.

Sights

Naturally the 75 comes with a fine set of adjustable target sights, and I’ll give you a better look at them in future reports. The front sight has replaceable inserts that are early 1980s vintage, which is to say a solid post or aperture. This one came with a post installed and the rest of the inserts in a box. I will replace it with a clear aperture that allows for more precise aiming as well as not shooting at the wrong bull. More on the sights when we get to accuracy.

The wood

Back when this rifle was new manufacturers were using walnut for their stocks. This one has a nice bit of figure in the butt. The remainder of the stock is straight grain except for the vertical pistol grip. It also has some figure which means the grain isn’t straight there, either. That’s desirable, because a 10-meter target rifle stock is very prone to break at the wrist where the wood is thinnest and also straight grain. Feinwerkbau even put vertical wooden posts into their grips on later rifles to strengthen this sensitive area.

The metal

I hope the pictures show a little of the deep polish and bluing on the metal parts. I had to lighten them to show details in things like the logo and the date code, so you don’t get the full appearance of the miles-deep polish. Only the barrel is intentionally matte, and that is to cut down reflections when sighting.

Summary

That’s your first look at this fine old target rifle. Wayne entrusted it to me to care for and that’s an obligation I both respect and intend honoring. Stay tuned for lots more fun.