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

Icarry Springfield Sa35 Polished 1
Icarry Springfield Sa35 Polished 1

I Carry: Springfield Armory SA-35 Polished in a Falco C631 Gorham Holster

In our latest episode of "I Carry" above, we're taking a closer look at the details of the new Springfield Armory SA-35 Polished, and we're packaging it with a high-quality leather holster from Falco Holsters, along with a new EDC knife from Work Sharp.

ATF Suffers Major Cybersecurity Incident

On Aug. 27, the Bureau of Alcohol, Tobacco, Firearms and Explosives announced that an outside group had breached its systems in what it termed a "major incident."

The Armed Citizen® Aug. 28, 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 Conversation About Gun-Making in America

Recently, a paper titled “The American Tradition of Self-Made Arms" written by Joe Greenlee, director of NRA-ILA's Office of Litigation Counsel,was cited by a court in an important ruling on frame-or-receiver litigation.

The Model 87 Ultra Special: A Rare Survivor of Ithaca's Final Gamble

In the spring of 1990, an 18-year-old received a shotgun he didn't order. The Ithaca Model 87 Ultra Special he got instead was the last gasp of one of America's most iconic shotgun makers.

As Gun Sales Stay High, Violent Crime Hits a Historic Low

According to a recent report from the FBI on national crime statistics, violent crime has decreased 9.3 percent from 2024, marking the largest year-to-year drop since the 1930s.

Interests



Get the best of American Rifleman delivered to your inbox.