Part 1 A short history of the spring-piston power plant
Part 2 A short history of the CO2 airgun
Part 3 A short history of the precharged pneumatic airgun
Part 4 A short history of the single stroke pneumatic airgun

This report covers:

  • History
  • Benjamin Automatic (model 600)
  • Benjamin 700
  • Crosman comes on the scene
  • Discussion
  • Air Venturi Seneca Aspen multi-pump
  • The future
  • Summary

Just a reminder that today is the day that Billy Joe McCallister jumped off the Tallahatchie bridge. Sorry — I can’t help myself!

Today we look at the multi-pump pneumatic. Growing up in America this was perhaps the most coveted airgun a kid could have. And the Sheridan Blue Streak was the most coveted of all. We were unaware of the Sheridan Model A — the multi-pump we now call the Supergrade. The Blue Streak was the pinnacle, as far as we were concerned.

Sheridan Blue Streak
Sheridan Blue Streak. This one has been with BB since 1978.

Sheridan Supergrade
BB’s Sheridan Supergrade is an older model with early features. Thanks to ATF sealant it now shoots as fast as any Supergrade ever made.

History

What I’m about to tell you comes from a one-time look at a multi-pump airgun (don’t know if the barrel was rifled, but probably not) that reader Larry Hannusch once showed me. As I recall, the exterior of the gun was brass and a shroud around the barrel held the compressed air. The butt plate was actually a place to rest your foot while you pumped the entire gun up and down many times. The gun hasn’t been fired to my knowledge in recent history, but it was probably on the low end of what a big bore PCP was capable of in the mid to late 1700s. Perhaps 400-450 f.p.s. for a .40? caliber ball? All of this is just my best guess from having seen the gun one time many years ago.

If there was one such airgun I’m sure there were others. But that is the only one of which I am aware.

My knowledge of multi pumps really starts with the St. Louis Air Rifle Company in 1899. They made a multi-pump single shot BB gun that had a wooden barrel! Actually there was a thin brass liner inside the wood. The valve was simple to the extreme. A rubber tube held back the compressed air. The trigger was a spring-loaded clamp that pinched the tube shut until it was pulled. The compressed air was then released. The faster the trigger was pulled the better the release.

St Louis airgun
St. Louis airgun of 1899.

Model maker Russ Snyder made 12 perfect replicas of this airgun around 1997 and I owned one for a time. As I recall the velocity was around 200 f.p.s. with a steel BB.

Walter Benjamin acquired the St. Louis Air Gun company around 1901/2 and began selling guns as Benjamins from that point on. He was proud that his guns only used air and “… had not a spring about them.” According to his literature they were the only true airguns made in the U.S.

In the early part of the century his rifles graduated quickly through several lettered models. Up until model G they required the quick pull of the trigger to exhaust the air fast enough for the shot. After that the valve was modernized into what we expect today. A pull releases a striker that knocks open the valve for the shot.

Benjamin Automatic (model 600)

The Benjamin Automatic was a 25-shot BB repeater than held enough air for two or three quick shots. All you did was pull the trigger and the gun fired. It came on the market in 1928 (some say 1930) and lasted for a few years, but was never as successful as the single shot models. I believe it confused shooters who didn’t understand the relationship between the air remaining and the possibility of a shot.

Benjamin 700

The Benjamin 700 came out in 1930 and was also a 25-shot BB repeater, but it had a bolt action that gave shooters time to pause and consider where they were with air. It also got several shots per fill and I tested that for you in this blog.

Crosman comes on the scene

Around 1923 the Crosman Seed Company brought a unique multi-pump air rifle to market. Like the Benjamins of the time it was a front pumper, meaning that the pump rod came out the front of the gun. If you read my report on the Benjamin 700 you’ll discover that you need very few pump strokes with such a mechanism, because each one pumps so much air. The downside is front pumpers are hard to fill — very hard!

Benjamin 700 pump out
The Benjamin 700 was a front pumper.

I stuck the picture of the Benjamin in here to show what a front pumper looks like. Crosman recognized right away that wasn’t the way to go and in 1924 they came out with their underlever pumper that soon became the .22-caliber model 101 and the .177-caliber model 100. Benjamin followed suit many years later but by then Crosman has zoomed ahead and Benjamin never caught up.

Build a Custom Airgun

Discussion

Let’s stop and consider the guns we are talking about. They are all multi-pumps which means you can put in a variable number of pumps to vary to power of the shot. That has always been the multi-pump’s claim to fame.

Are they powerful? Not that much. The .20s and .22s can get up to around 14 foot pounds and that’s where they top out. The Japanese company Sharp made multi-pumps that topped 20 foot-pounds, but their triggers became harder to pull the more air they held. However, they did know what to do about it. My sidelever Sharp Ace Standard Target has a trigger than is measured in ounces regardless of how much it’s pumped.

Sharp Ace Pan Target
Sharp Ace Standard Target.

Air Venturi Seneca Aspen multi-pump

The Seneca Aspen multi-pump is a PCP that has a pump built into the airgun! What that means is you can fill it from a tank or you can pump it up yourself. This is exactly what the easy-chair engineers have been designing in their dreams for years. Then FX came along with their Independence that does exactly that and everybody changed their tune to —“I would buy one, if only it wasn’t $1,600!” Well, this one isn’t.

Seneca Aspen PCP pump
Seneca Aspen multi-pump PCP.

I tested not one but two of those air rifles for you and they came through quite well. The multi-pump part works, as does the PCP part.

The future

What am I suggesting today? I’m telling you that the world of multi-pumps still has lots of room for advancement. Airgun designers haven’t begun to incorporate all the things the market says they want, but maybe that’s for a good reason. You see — multi-pump pneumatic users are extremely conservative. They will tell you all sorts of things they want, but getting them to open their wallets is a different matter. The Crosman 362 and the Seneca Dragonfly Mark 2 are the exceptions to the rule — brave excursions into a world of tight money and stubborn shooters.

Summary

If I’m right about the mid to late 1700s date for the first multi-pump this is an airgun design that’s 275 years old. Yet it has seemed to advance in spurts, then hunker down for some time.

Where should it go from here?