Rifleman Q&A: Bullet & Primer Sealant

by
posted on September 19, 2021
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
Qamain

Q. I recently purchased some pulled, military surplus bullets. They have quite a bit of black residue on them that I assume was the water sealant between the bullet and inside the case mouth. What is the sealant material made of?


A. The sealant used by ammunition manufacturers on bullets is usually an asphalt-based chemical. Very few handloaders think it to be necessary, and I personally don’t know of any who do try to duplicate the factory waterproofing. Handloads are typically used within a few years, and in that time, with the handloads stored in reasonably uniform conditions, there is very little possibility of moisture penetrating the physical seal between bullet and case mouth. The same goes for primer sealers. These two seals are primarily used on military ammunition, where storage and time considerations are more important.

—Dave Andrews


This “Questions & Answers” was featured in the October 2004 issue of American Rifleman. At time of publication, "Questions & Answers" was compiled by Staff, Ballistics Editor William C. Davis, Jr., and Contributing Editors: David Andrews, Hugh C. Birnbaum, Bruce N. Canfield, O. Reid Coffield, Charles Q. Cutshaw, Charles M. Fagg, Angus Laidlaw, Evan P. Marshall, Charles E. Petty, Robert B. Pomeranz, O.D., Jon R. Sundra, Jim Supica, A.W.F. Taylerson, John M. Taylor and John Treakle.

To subscribe to the magazine, visit NRA membership page here and select American Rifleman as your member magazine.

Latest

9X18 Makarov
9X18 Makarov

Shooting Surplus: Finding Affordable Mil-Surp Ammo in 2026

Today, the market for mil-surp ammo is vastly different than it was even just a few years ago. If you're a military-surplus collector and shooter, what should you look for in 2026? Here's our guide.

Colt Electro-Optics Introduces New Red Dots & Magnifier

No stranger to rebirth, Colt has recently spun off an optics division to make sure that, in a world where optics are considered to be standard equipment, a fully kitted-out gun can be all-pony.

What This Huge NFA Ruling Means for Gun Owners

The recent ruling in Jensen v. ATF and the subsequent lack of an appeal by the U.S. Department of Justice has left many gun owners with questions about purchasing NFA items. Here is some guidance.

Gun of the Week: Smith & Wesson Model 386 Night Guard

In partnership with Lipsey's, Smith & Wesson recently re-introduced two of its classic Night Guard revolvers, the Models 386 and 396, which are chambered for the .357 Magnum and .44 Special, respectively.

The Armed Citizen® Aug. 14, 2026

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

A (Slightly Confusing) History of Colt's Police Positive Revolver

For one of the most popular law-enforcement revolvers ever made, the history of the Colt Police Positive isn't nearly as linear as one would think it'd be.

Interests



Get the best of American Rifleman delivered to your inbox.