I posted this over at another site, but I thought it might be of interest here. Another person was asking about using standard safety glasses, to which I recommended only using MIL-spec rated eye protection. I decided to shoot both a piece of Lexan, which is supposed to be 250 times stronger than glass, and a pair of MIL-spec glasses. As luck would have it, I actually needed the eye protection out in the garage today.
First up for execution is a piece of 2.56mm Lexan polycarbonate. Shooting distance was 13 meters using JSB Exact Jumbo 18.13g at 866fps with an energy of approximately 32Ft lbs (regulated PCP gun with full charge). Two shots were made.
The bottom of the Lexan was stuck into the ground about 10cm deep, and supported by a stick in the ground.
As you can see, the pellet was not able to penetrate the Lexan. However, it created quite a pointy-bit on the inside of the sheet. This sheet is thicker than the average pair of eye protection. Also note that the sheet shattered into pieces. I imagine that the shards could be potentially dangerous projectiles.
Next up, I sacrificed my pair of safety glasses. According to the manufacturer, they pass the MIL-PRF 32432 High Velocity Impact Standard. Thickness as measured was 1.98mm (2.2mm according to the manufacturer).
The ear pieces were stuck into the ground, and the nose bridge piece was supported by a stick. Shooting was completed as above, using the same gun, distance, and pellets. One shot to each lens.
Make no mistake, even with MIL-spec eye protection, it's going to hurt. The first shot shattered the glasses into several pieces. Note however that the lenses remained intact. There was slight penetration to both lenses, but the pellet was not able to pass through.
As with the Lexan, a sharp protuberance was produced on the inside of the lens. I held both lense up to my eye tightly, and because of the curvature, was unable to get the sharp indent anywhere near my eye.
Sorry, but I don't have a pair of non-MIL-spec glasses to shoot.
I hope people who shoot in glass prescription or non MIL-spec glasses take note of my experiment. Those who choose to shoot sans glasses all together, well...maybe this will guide you toward changing that habit. I'm sure that at some point in our shooting career we've all shot without eye protection. I've had two friends that were injured by ricochet from their own pellets. I myself have had a few close calls. It's a sobering moment when you hear that pellet whiz by your head and strike something behind you.
Eye protection. Use it. Use properly rated eye protection, and always wear it when shooting.
On a side-note, I would also encourage the PCP shooters to wear eye protection when filling their gun(s). I've had a Foster connection come loose while filling, which caused the whip to flail around at a very high speed. The whip struck some plastic piping for my shop-vac, and shattered a hole in one of them. Could have easily been my eyes.
