Ballistic gelatin test results : Air Guns

[Brass Fetcher]

Don't know where else to post this, but I wanted to get the results out to you. Mods, if it makes a difference, the tests were done with pellet rifles.

This was an informal test, and I thought that I would try something new, as I am about out of gelatin powder and this should be my last test or two before I quit the gelatin for good.

Anyways, I used a pump-up Crosman 0.177" (the thirty dollar one from Wal-Mart) gun and a Crosman 0.22" gun (with ~ 20" barrel). No chrono was used, as the testing was done in my garage. The 0.177" was pumped ten times for all shots - likely giving a fairly constant 'juice' input to all 0.177" projectiles.

In order to increase expansion on the HP pellets, I cut a 'x' shaped cut into the face of the pellet using an X-acto knife. The cut went the length of the cavity, and stopped at the base of the cavity. The 'reversed' pellets were just that - I turned them around in the gun and fired them, giving hollowpoint-esque expansion. There are also two denim tests in there, to simulate a rodent with a thick hide (I guess ). Left to right in the pic is equal to top to bottom in the listing of results.

Gamo .177 Magnum (reversed) = 0.254”; Penetration = 1.54”

Gamo .177 Pointed (reversed) = 0.253”; Penetration = 1.50”

Gamo .177 Match (reversed) = 0.270”; Penetration = 1.50”

Beeman 0.22 Crow-Magnum (reversed, 1 layer of denim) = 0.320”; Penetration = 2.24”

Gamo .177 Match = 0.178”; Penetration = 3.03”

Gamo .177 Pointed = 0.174”; Penetration = 4.05”

Steel .177 BB = 0.171”; Penetration = 2.95”

Lead .177 BB = 0.176”; Penetration = 3.90”

Beeman 0.22 Crow-Magnum (reversed) = 0.318”; Penetration = 2.68”

Beeman 0.22 Silver Bear (reversed) = 0.360”; Penetration = 1.54”

Beeman 0.22 Silver Bear = 0.221”; Penetration = 3.78”

Unknown pointed lead pellet 0.22 = 0.216”; Penetration = 5.08”

Beeman 0.22 Crow-Magnum = 0.221”; Penetration = 4.21”

Beeman 0.22 (X-cut) Crow-Magnum = 0.240”; Penetration = 3.70”

Beeman 0.22 (4-layer denim) Crow-Magnum = 0.231”; Failure to penetrate
final layer

 

[griz]

You got some impressive expansion with some of those. More than I thought they would expand. Thanks for the report.

 

[JohnKSa]

The unknown pointed pellet looks like it might be a Silver Jet to me. If you post a side view pic of it, I might be able to ID it.

Kinda surprised that the Crow Magnum's didn't expand. I would like to know the velocity on those--they are one of the few HP pellets that actually do expand if the velocity is sufficient.

Good test--and a good illustration of why conventional airgun hunting/pest control is all about precision accuracy. There simply isn't enough power in a conventional airgun to rely on anything other than perfect shot placement.

 

[Brass Fetcher]

I recall that name - they are Silver Jets. Thanks. I didn't get to use the chronograph, but the gun was a Crosman 2260, if that helps. The .177" gun was a Crosman Pumpmaster 760.

 

[444]

That was very interesting.
It is too bad that you didn't chrono them. That would have been even more interesting to see how pellet weight vs. pellet velocity plays out.

 

[DBR]

IMHO looking for expansion with air guns is the wrong approach. You need penetration. I have had the best results up to woodchuck size animals with 22 or 25 caliber flat point match pellets.

 

[RyanM]

Interesting. Is 10 pumps on a steel BB enough to get it up to calibration velocity? I ask not only for calibration purposes, but also because I'm looking for a cheap pump gun, so's I can calibrate my modeling clay at different temperatures. Using the extremely cheap junk from Wal-Mart, for now.

 

[Brass Fetcher]

RyanM,

It looks like you and I are both shopping at the same store. The calibration BB gun that I have used for 2 years is the Crosman 760 pumpmaster. In my part of Florida, year round, 16 pumps has given me no lower than 603 ft/sec muzzle velocity with a steel BB. Don't worry about hurting the gun - it's like a Jennings, if it breaks or needs cleaning, throw it away and buy another.