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

Zenithmrds 01
Zenithmrds 01

MRDS: Zenith’s American-Made Roller-Delayed Rifle For The 21st Century

While the roller-delayed blowback mechanism has proven reliable in platforms like the Heckler & Koch G3, Zenith Firearms has taken this innovative operating system and paired it with a modern, AR-style feature set in its MRDS.

Remington Announces 4th Annual Shoot To Cure Fundraiser

Now in its fourth year, the Shoot to Cure fundraiser is scheduled to take place on September 19 at the historic Remington Gun Club in Lonoke, Ark.

Rifleman Review: Walther Arms PD380

For its latest compact carry pistol, the PD380, Walther Arms combined elements of its Performance Duty Pistol series with its legacy PK380 platform.

Black Beauty: Nimschke’s Masterpiece Sold By Rock Island Auction

German-born Louis Daniel Nimschke is widely recognized as one of the most talented and prolific firearm engravers of the 19th century.

Springfield Updates Saint Victor AR-15 Lineup

Since 2019, Springfield Armory has offered its Saint Victor line of AR-15s with enhanced features, and for 2025, the company has updated those features to keep pace with consumer demands.

In Memoriam: Wiley Clapp

Longtime American Rifleman Field Editor and contributor Wiley Clapp passed away June 4, 2025. He was 90 years old.

Interests



Get the best of American Rifleman delivered to your inbox.