Diana 25 smoothbore pellet gun: Part 3

by Tom Gaylord, a.k.a. B.B. Pelletier

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Diana 25 smoothbore
This Diana 25 smoothbore was made during World War II.

What a topic to follow a twist-rate report — one about a smoothbore! Today, we’ll look at the accuracy of the WW II-era Diana 25 smoothbore airgun. This is a play-day for me because this gun is so non-finicky and trouble-free. It’s the way I wish all airguns could be. Just load and shoot. No special handling beyond the basic artillery hold, and no need to treat it like it’s a vial of nitroglycerin.

Shoot from 10 meters
I decided to shoot from a rest at 10 meters just because this is a smoothbore, and I had no idea of what results we would get. I hoped it would hit the paper with all shots. That would be good enough. But nothing beats shooting, so that’s what I did. read more


Pellet velocity versus accuracy test: Part 11

by B.B. Pelletier

Announcement: Dammion Howard is this week’s winner of Pyramyd Air’s Christmas Big Shot on their facebook page. He’ll receive a $50 Pyramyd Air gift card plus another $50 in goodies!

Dammion Howard (left) shows off some new airguns he found under the tree this year!

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Happy New Year from Tom & Edith!
One nice thing about watching a TV program is that it only takes an hour or less to view. You have no sense of the man-weeks of work that go into a short production on screen. Sometimes, the same thing happens in the world of airgun blogs.

I won’t say I’ve been dreading today’s report; but from past experience adjusting the HOTS on the Whiscombe rifle, I knew it might take longer than anyone could imagine to get a good result. It’s easy to say, “Adjust the HOTS for optimum performance with a certain pellet.” Actually doing it is where you discover if it’ll be easy or hard. The report I have for you today was very hard. read more


Pellet velocity versus accuracy test: Part 10

by B.B. Pelletier

Announcement: Kevin Currie 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.

Kevin Currie is shown shooting a tuned .177 Gamo CFX with his son and dog. He says his CFX is scary accurate!

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Merry Christmas!
For those who celebrate Christmas, Merry Christmas from Edith and me! This is our last opportunity to wish you a Merry Christmas before Sunday, but I would like to hear on Monday from anyone who received an airgun, airgun-related gift or a firearm for Christmas. I’ll tell you what I got, too. read more


Pellet velocity versus accuracy test: Part 9

by B.B. Pelletier

Announcement: Joel Cole 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.

Joel’s winning photo is of his niece, Paysen. He was teaching her to shoot a Crosman 66 over Thanksgiving weekend.

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Today, we’ll complete the testing of the four pellets at four different velocities in the Whiscombe rifle. The premise of this test has been to explore the effects of velocity on accuracy by shooting the same pellets in the same pellet rifle at four differing velocities. I will make today’s report and comment on how the test went, but this will not be the final installment of this test. There will be at least one more summary report that puts all the data into perspective. And if there are side issues to explore, maybe there will be more reports. read more


Pellet velocity versus accuracy test: Part 8

by B.B. Pelletier

Announcement: Aaron Weinstein 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.

Aaron’s winning photo. He’s holding a GSG 92 CO2 BB pistol made by an airsoft manufacturer that now also produces realistic lookalike airguns.

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This is an exploration into the theory that high velocity reduces pellet accuracy when it reaches and exceeds the transonic speed region, or about Mach 0.8 to 1.2. We have thus far examined four different .177 pellets at three different speed levels, produced by shooting them in a Whiscombe JW75 spring rifle. Because all pellets have been fired in the same barrel and powered by the same powerplant, the conditions have remained the same, except for their velocities. That was altered by the use of air transfer ports of varying sizes, that passed the compressed air at differing rates. read more


Pellet velocity versus accuracy test: Part 7

by B.B. Pelletier

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Before we begin today’s report, I want to reflect on a truth that helps explain why we’re sometimes dissatisfied with things when we get them. I was at the range last week testing some airguns, and I was using my Celestron 70C spotting scope, like I always do. This scope is good at 50 yards, but becomes marginal at 100 because it cannot resolve the smaller bullet holes. I don’t mean pellet holes, I mean .22-caliber bullet holes in the black bullseye at 100 yards.

A friend brought his Burris spotting scope to the range for me to compare, and the difference between the two was night and day. His scope was sharp enough to see small spiders walking on the target paper at 100 yards! read more


Pellet velocity versus accuracy test: Part 6

by B.B. Pelletier

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For the benefit of readers who have landed on this article first, this is the sixth test in a series of reports designed to test how velocity affects accuracy. I’m using a Whiscombe JW75 breakbarrel/underlever rifle with a .177-caliber barrel installed. That way the same powerplant is being used for each test. I’m controlling the power of the gun by the use of different air transfer port limiter screws that allow less and less air to past through.

The Whiscombe rifle uses dual opposed pistons that come together to compress the air when the gun is fired. The rifle has no recoil and just a minor impulse that can be felt — yet it’s one of the most powerful spring-piston air rifles ever made. My rifle can produce over 30 foot-pounds in .25 caliber. read more