Back in 2000, I ordered a 50 round box of a rather peculiar type of surplus military 7.62 NATO cartridge from Sportsman's Guide or Cheaper Than Dirt. I don't remember which. They were fairly inexpensive, perhaps 5 cents apiece.
As a unit, the entire cartridge with the exception of the brass case head is made of a blue plastic material. This included the projectile which is actually molded as part of the plastic case. When the cartridge is fired, there is a weakened area at the case mouth which allows the projectile to separate from the case body. The resulting bullet weighs about 10 grains and has a sectional density of less than half that of a 0.177 caliber air gun pellet
The case head has a rebated rim measuring 0.442 inches in diameter, about .030 inches smaller than that of standard 7.62 NATO ammunition.
As best as I could determine, these cartridges were manufactured by Dynamit Nobel for use by the British Military for firearms training at distances of up to 25 meters. These low power rounds are designed to used in FN FAL rifle equiped with special lightweight training bolt. With this system they provide just enough energy to cycle the action in a realistic manner.
In order to prevent the use of standard 7.62 ammunition with the training bolt and the inevitable injury or death to the user, the recess on the bolt face was designed so that it would only fit the rebated rim of the training ammunition but be too small to accept standard 7.62 NATO rounds.
As plinking ammunition, they were okay out to about 25 yards but they lost velocity rather quickly. In fact I recovered several of the bullets lying on the ground around the 75 yard line of the range.
In July of 2000, I chronographed these cartridges, fired from a Spanish FR7 with a 21 inch barrel. The average muzzle velocity for this round was 437 feet per second . The following table shows the results generated by a ballistic calculator for a 50 yard zero with a 10 grain, 0.308" dia. bullet with a muzzle velocity of 437 fps.
Ballistic Table for DAG 7.62 NATO Blue Plastic Ammo for Zero at 50 yards with 10 grain bullet.
As you can see from the table, the bullet drop at 100 yards is a little over 9 feet assuming that it does not hit the ground before then. Compare this to the 147 grain full metal jacket bullet of the standard 7.62 x 51 mm Nato M80 cartridge which has a muzzle velocity of a little over 2700 feet per second and drops less than 3 inches at 100 yards.
Truth in Advertising?
In 2009 these same cartridges seem to have reappeared on the market except that they were now being advertised at the much higher price of 16 to 20 cents a round and were said to have the improbable muzzle velocity of 4400 feet per second. This assertion piqued my curiosity. At such a high muzzle velocity, I would expect that the heat generated from the high pressure gases of the burning propellent as well as the friction of the bullet in the barrel would be sufficient to turn the projectile into a molten globule of plastic thereby destroying any hope of accuracy.
The following regarding this round was taken from the Sportsman's Guide Website on December 25, 2009;
Accurate with little or no recoil. 11-gr. plastic projectile. Brass head (DAG headstamp). Accurate up to 320 yds. Ideal for indoor ranges.
Non-corrosive, non-reloadable with lead-free primer. Note: Will NOT cycle in semi / full-auto guns. Approx. Muzzle Velocity: 4,400 F.P.S. Muzzle Energy: 472 ft.-lbs. 50 rds. / box.
Web Address - http://www.sportsmansguide.com/net/cb/308-short-range-ammo.aspx?a=556342
Although I fired most of the cartridges that I purchased 9 years ago, I did keep a few due to their unusual nature. They appear to be identical to those pictured on the Sportsman's Guide Website. The headstamp reads "DAG 7.62 x 51 " and the primer is ringed with a green sealant. I took one of these saved rounds apart (pictured below) and found that the bullet weighs 9.9 grains and that the propellent charge is 12.2 grains of a grayish green extruded powder. Additionally the cartridge is boxer primed.
My suspicion is that the actual muzzle velocity of the DAG blue plastic cartridges on the market has been overstated by a factor of ten perhaps by someone who did not realize that their chronograph will display any velocity below 1000 feet per second to the first decimal place. So 440.9 appears to be 4409 fps. Of course, I am not willing to pony up the money to buy this ammunition at the currently inflated prices to verify this.
A Simple Test
Using a ballistic calculator, I came up with this simple test to see if this ammunition is performing as advertised without the use of a chronograph.
- Using DAG Training ammunition, from the bench, zero a rifle to hit point of aim 25 yards.
- Using same sight setting, fire a five round group from the bench at the same target at 50 yards
At 50 yards, the group should be less than one inch below the point of aim if the muzzle velocity is truly greater than 4000 feet per second.
If however, the rifle shoots a foot or more low at 50 yards with a 25 yard zero, then the muzzle velocity being produced is something less than 500 feet per second.
One thing is for certain, even if it were possible to achieve a muzzle velocity of 4400 f.p.s with this ammunition, as a practical matter, the poor sectional density of a 10 or 11 grain 0.308" extruded plastic bullet would make it impossible to be "Accurate up to 320 yds" as stated in the Sportsman's Guide catalog /website. To have a zero at 320 yards(300 meters), your rifle sights would have to be adjusted to hit 17 feet high at 100 yards with this load.
Another consideration is that even a light wind would play havoc with the accuracy of this light weight projectile over such a long distance.
Ballistic Table for 11 grain 0.308" Bullet MV 4350 fps.
I would be interested in hearing from anyone who has personally chrographed DAG blue plastic ammunition acquired since 2009. Please email me at firstname.lastname@example.org. The following details would be helpful.
- Test Firearm make and model
- Barrel length
- Chronograph manufacturer and model
- Where the ammunition was purchased
- Markings on the ammunition packaging, headstamps
- Individual Muzzle velocity values for each shot in the string
PLEASE NO SECOND OR THIRD HAND INFORMATION OR BEST GUESSES.
Update March 2012
Dirk B. of San Diego reports purchasing 1000 rounds of the DAG blue plastic ammunition hoping that it would be accurate out 100 yards.
The place of purchase was not specified but the box was marked 95.
Fired from a bolt action Ruger Gunsite Scout Rifle with a 16.5 inch barrel, He reports that there was good accuracy out to 25 yards, things got iffy out to 50 yards. 100 yards was a waste of time. He also reports about 20 percent of the cartridges misfired.
As of 2012, no recent chronograph data for this ammunition has been received.