Polymer-coating of bullets and polymer composite bullets

About 20 years ago American companies that produce high-powered rifle ammunition started using polymer tips on some of their bullets to achieve better flight characteristics during long-range shooting.

The polymer tips were easier to form than lead tips, and when combined with high ballistic efficient bullets with boat tails, flatter trajectories were obtained and more foot pounds (ft./lbs.) of energy were retained at distance. The primary problem with polymer tips was that they tended to warp due to extreme heat produced by velocities over 2,000 feet per second (FPS), affecting accuracy at several hundred yards.

Hornady ELD ammo and Scirocco II are the two polymer ballistic tip bullets I am familiar with. The ELD is guaranteed to retain it’s shape far beyond 400 yards with it’s Heat Shield Technology and the Scirocco II bullet seems to resist warping when fired at 3,000 FPS or a little more from my .300 WBY Mag. Both bullets have worked well for me out to a little more than 400 yards. Accuracy has been very satisfactory when I manage to do my part. I have also heard some high praise for a Nosler ballistic tip bullet, but have not had any personal experience with it.

A couple of years ago I was at the Oregon Trail Gun Club watching a cowboy shooting event. One of the venders that was also there, was giving out samples of polymer-coated bullets.

Polymer-coated bullets have been used for about two decades outside the United States. Advantages of polymer coated bullets are less friction between the bullet and the bore, less smoke, less debris such as lead left in the barrel, no toxic off-gassing, contains no Moly-Disulfide to gum up your dies, works great in bullet feeders, great for indoor shooting where lead bullets are restricted, non abrasive to the barrel, coating does not rub off on your hands, and poly-coating does not build up in the barrel.

The most common source for polymer-coated bullets is Hi-Tek, made by J&M Specialty Products from Australia. The representative that was handing out polymer-coated bullet samples was from Leatherhead Bullets which purchased them from J&K Specialties, and is now in the process of merging with Gallant Bullets in Utah.

Some companies use their own proprietary polymer, moly, or Teflon based mixtures. However, Teflon may be illegal since it is commonly used in Armor Piercing bullets.

Polymer-coating is generally good at velocities blow 2,000 FPS with1,200 to 1,500 FPS being the norm. this makes polymer coated bullets primarily good for pistol velocities with some rifle ammunition such as .300 Blackout, .45-70, and .30-30 Winchester included. Velocities above 2,000 FPS create enough heat to warp the polymer coating, so it is recommended that polymer coated bullets not be used with ammunition that generates more than 2000 FPS muzzle velocities.

Recently a company, Polycase, has come out with bullets that are a mixture of powdered copper and polymer and are produced by injection molding. The bullets come in two types, solid or fluted. The solid bullets are called, Round Nose Precision, and the fluted bullets are called Truncated Nose Precision. The ARX (Advanced Rotational Extreme) bullet has three flutes in the nose that redirect hydraulic forces laterally.

At this time, Polycase bullets come in, .380 Auto, 9mm Luger, .38 Special, .357 Magnum, .40 S&W, .45 Auto and .45 Colt for handguns. Polycase loads both the round nose and ARX bullets for it’s handgun calibers, and the ARX is used in low velocity rifle rounds. Ruger loads only the ARX bullets.

The ARX bullets do not expand. They rely on the flutes , combined with the bullet’s rotation, to create hydrostatic shock to create a large temporary wound channel during penetration.

Polycase claims that ARX bullets create temporary wound channels that match or exceed any bullet in the same caliber. The ARX bullets have significant penetration in gelatin but generally stop by 16 inches, thereby reducing the risk of over penetration.

The Polycase composite bullets are new enough that I haven’t seen them in stores yet. They tend to be about 25 percent lighter than lead bullets of the same caliber.

It is evident that polymer-coating of bullets and the technology of producing polymer composite bullets is moving forward. We can only wait and see if they become popular once they are more readily available.

Smokey Merkley was raised in Idaho and has been hunting since he was 10 years old. He can be contacted at mokeydo41245@hotmail.com.

Post Author: By Smokey Merkley

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