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

Taurus TXM 01
Taurus TXM 01

TX Maxed: The Taurus TXM in 5.7x28 mm and .22 WMR

Using its TX series architecture yet again, Taurus is adding the 5.7x28 mm and .22 WMR to its chambering options with the new-for-2026 TXM.

Review: Federal's 6.5 Creedmoor +Peak Ammunition

Federal’s new 6.5 Creedmoor +Peak takes a long-range staple even farther.

New for 2026: Pulsar Thermion 3 Riflescope

Pulsar’s newest thermal scope offers longer range, sharper detail and expanded functionality.

AKs In The USA: The Current State of the American AK Platform

Despite it being the primary rifle of the enemy for most of its existence, American shooters have nonetheless warmed to the AK platform, creating an unlikely love story.

Demand for Guns, Ammo & Firearm Accessories Accelerates

October gun sales increased according to the National Shooting Sports Foundation (NSSF) estimate, but the quarterly reports from major manufacturers reflect purchases significantly higher.

The Armed Citizen® Nov. 9, 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.

Interests



Get the best of American Rifleman delivered to your inbox.