I once had UPS leave 25 pounds of bp on my front porch..... in a residential neighborhood.
And we weren’t home at the time, luckily it was still there when I came home..
That has been my only bad experience with them..and I have used them several times since.
USPS , is iffy at best... They will ship antique or muzzle loading parts/guns, but you may have too speak too the Post Master instead of the window clerk...
Fed Ex, I personally haven’t used that much
experience with...
Remember bp guns aren’t considered fire arms....
Manuals
DMM Revision: Mailing Firearms — Clarification
Effective November 7, 2011, the Postal Service™ will revise Mailing Standards of the United States Postal Service, Domestic Mail Manual (DMM®) 601.12.1 through 601.12.3 to clarify the standards surrounding the mailability of firearms.
These clarifications were prepared in collaboration with the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), and neither expands nor limits the current requirements for the shipment of firearms through the U. S. Postal Service®. Prior to this clarification, firearms mailing options were only provided to the prospective mailer through an ATF contact. The primary purpose of this article is to provide clarity for those individuals seeking advice on the mailing of firearms and related items and to help reduce the number of questions submitted to the ATF.
Additionally, the Postal Service is providing guidelines for the mailing of air guns, which reflect reasonable practices commonly used in the industry.
Postmasters may provide these revised guidelines to firearms mailers immediately.
Mailing Standards of the United States Postal Service, Domestic Mail Manual (DMM)
* * * * *
600 Basic Standards for All Mailing Services
601 Mailability
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12.0 Other Restricted and Nonmailable Matter
[Revise title of 12.1 as follows:]
12.1 Firearms
12.1.1 Definitions
The terms used in this standard are defined as follows:
[Delete current items 12.1.1a and 12.1.1g in their entirety and replace with the following.]
a. Firearm means any device, including a starter gun, which will, or is designed to, or may readily be converted to, expel a projectile by the action of an explosive; the frame or receiver of any such weapon; any firearm muffler or firearm silencer; or any destructive device; but the term shall not include an antique firearm.