Chronograph tips

by Tom Gaylord
Writing as B.B. Pelletier

This report covers:

  • How it works
  • The evolution of the personal chronograph
  • The advent of the skyscreen
  • Advantages of skyscreens
  • Fly in the ointment
  • Screen placement problem one
  • Screen placement problem two
  • Shooting perpendicular to the skyscreens
  • Lighting
  • Odd chrony info
  • Summary

Reader Buldawg asked for this report, but several other readers chimed in and seconded his request. I have written about this before, but we have so many new readers that it is probably time to do it again. There are several definitions for the word chronograph, including a very accurate wristwatch, but the chronograph I am talking about today is one that measures the velocity of a projectile. We are interested in pellets, mostly, but the chronograph was created to measure the velocity of bullets.

How it works

A chronograph works by counting time between two events. In today’s discussion those events are the passing of a projectile through two electronic screens. The first one starts the clock and the second one stops it. So we call these screens the start and stop screens. The counter parses time into very small intervals. In the case of my Oehler 35P chronograph the counter divides each second into 4 million units. So time between the start and stop screen is measured in 4-millionths of a second. read more

Shooting Chrony Alpha Master

by Tom Gaylord
Writing as B.B. Pelletier

Alpha Master chronograph
Shooting Chrony Alpha Master chronograph has a control box with display that separates from the skyscreens by 18 feet. These chronographs are shown with their light diffusers attached, but I don’t use them. Read why in the report.

This report covers:

  • What about the false triggering of the skyscreen?
  • Start screen — stop screen
  • Atomic blast wave
  • The solution to false triggering
  • How I use the new chronograph
  • Battery operated
  • Light diffusers
  • Summary

As you may be aware, I shot my Shooting Chrony Alpha chronograph with the Benjamin Bulldog big bore air rifle. It wasn’t the rifle’s fault — it was mine. There were other shooters on the range, so I had to place the chronograph about 10 feet in front of my position to get the skyscreens out from under the metal roof that hangs over the firing line. For range safety rules, I could not get closer to the chronograph. So, I was pointing the airgun to shoot over the skyscreens. read more

Airgun lubrication — gas guns

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

Airgun lubrication — spring guns: Part 1
Airgun lubrication — spring guns: Part 2

This report addresses:

• Molecules versus atoms
• Crosman Pellgunoil
• Can’t over-oil with Pellgunoil
• “Fixing” leaking guns with Pellgunoil
• Transmission stop leak oil
• Oiling moving parts
• Ballistol

Let’s look at lubricating gas guns — and by “gas,” I mean CO2. What I’m about to say will also work on airsoft guns that operate on green and red gas, because both those gasses work similar to CO2; but there are no pellet or steel BB guns that run on any gas except CO2 (excluding air). read more

Airgun lubrication — spring guns: Part 2

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

Airgun lubrication — spring guns: Part 1

This report addresses:

• Identifing and lubricating high-stress parts
• Lubricating with moly
• Lubricating triggers
• Lubrication intervals
• Lubricating mainsprings
• General lubrication
• Preserving the airgun with oil

Well, the immediate response we got to the first installment of this report made it one of the all-time favorites. In that report, we looked just at the piston seal, which I said was half of the lubrication solution for a spring gun. Today, we’ll look at everything else.

Parts under high stress
The moving parts of a spring gun are the powerplant parts, the trigger group and either the barrel, when it’s used as to cock the gun, or the cocking mechanism if the gun isn’t a breakbarrel. When airguns were simpler and less stressed, all of these parts could be lubricated with gun oil or lithium grease. But today’s guns are stressed to higher limits and generally need something more specific and better-suited to each application. read more

What do I do?

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

Today’s report comes from a question asked by blog reader Richard, who is perplexed by his Benjamin Marauder air rifle. He said he wondered what pressure he was supposed to fill his gun to, and then at what pressure he was supposed to stop shooting.

As the days passed after asking his question, Richard eventually figured it out on his own and now knows what to do, but today’s report is for all those who haven’t figured it out yet, as well as for those who have held off buying a precharged airgun because they feel there’s so much they don’t understand.

More power!
At the Roanoke airgun show last weekend, I talked to a shooter who claimed he pumped and pumped his old Sheridan until it cracked like a .22. Now, I know that’s impossible and I’ll tell you why. read more

Testing the effect of barrel length on a precharged rifle

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

This test was done for blog reader GunFun1, who asked to see what effect barrel length has on velocity. Though it appears simple, this test took 2 days to conduct because of barrel changes and other sundry things. But what was learned far exceeded my hopes, so the effort it took was well worth it.

I tested with an AirForce Talon SS, which has the facility to accept interchangable barrels. All testing was done with the rifle in .22 caliber, which means every barrel used was that caliber. I used the factory-installed 12-inch Lothar Walther barrel, an optional 18-inch Lothar Walther barrel and an optional 24-inch Lothar Walther barrel. read more

How chronographs changed airgunning–and not always for the best!

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

This topic was suggested by veteran blog reader Kevin. I liked it because it gives me a chance to say some things to the new airgunners; better yet, it’s a great way to start a discussion among all you readers.

I will touch on the things about chronographs, which are near and dear to me, but I think my role today is simply to get the ball rolling. We have enough readers with chronograph experience that I’m sure they’ll share a lot of their own viewpoints — some of which may never have occurred to me.

What is a chronograph?
The term chronograph means different things to different people. To an horologist, it might mean a particularly accurate instrument (watch or clock) to record the passage of time; but to a shooter, it means an instrument that’s used to measure the velocity of a projectile. It still records the passage of time, but also performs an additional calculation to convert the results into velocity. As incredible as it sounds, we’re able to measure the speed of a pellet or bullet moving hundreds, or even thousands of feet per second with an instrument we can buy for as little as a hundred dollars. read more