Meeting Major Power Factor With A 4-Inch Revolver Barrel And Moon Clips

by
posted on April 8, 2020
** 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. **
moonclip-1.jpg

From the vault: A reader submitted this question about meeting Major Power Factor (PF) while shooting a revolver with a 4-inch barrel. The principles outlined in the response still apply today. From the July 2006 issue of Shooting Sports USA.

Q. My revolver is loaded with a moon clip and therefore requires a load with a Power Factor of 165. What loads do you suggest to reach 165+ in a 4-inch revolver? Can the round be loaded to longer length than what is specified for autoloaders?

A. While it is true that loads described in manuals were developed for autoloaders, it is not necessarily true that none of those same loads will make Major PF in a revolver.

As a reference, the Speer Reloading Manual #13, cites velocities that were obtained from a 4-inch pistol barrel. Some of these loads exceeded 185 Power Factor.

Through research and experience, it can be seen that there is a very small difference in velocities from the same loads fired in both types of pistols—revolvers and autoloaders. Even if there was some loss in velocity due to the barrel/cylinder gap, many loads would still make the Power Factor. Even though this may be true, it is still recommended that you chronograph your loads in the specific pistol you are using in order to get the exact velocity. The Speer manual offers plenty of options to start with.

The round loaded can certainly be in a longer overall length cartridge, however this may lead to a slightly lower velocity and an outcome that is the opposite of your goal.

Have a question about the shooting sports? Please email us at [email protected].


See more: Why Does Ballistic Coefficient Improve With Heavier Bullets?

Latest

Johnrussell RSS 1
Johnrussell RSS 1

Rising Shooting Stars: Jonathan Russell

Driven by discipline and a passion for marksmanship, 14-year-old Jonathan Russell is redefining junior rifle shooting with national records and championship performances.

Barnes and Sierra Turn Doppler Data Into a Smarter Ballistics App

TrueData is a new ballistics app using Doppler-measured bullet data and live weather inputs to deliver more realistic shot predictions.

Classic SSUSA: Kenda Lenseigne World Champion Interview

World champion Kenda Lenseigne shares her journey in cowboy mounted shooting, training secrets and her experience at the 2011 Bianchi Cup.

New: Smith & Wesson Model 1854 Chambered in 360 Buckhammer

Smith & Wesson expands its Model 1854 lever-action rifle lineup with a 360 Buckhammer option.

Ruger 10/22 Carbon Fiber: Lightweight Speed, Heavyweight Accuracy

Ruger’s lightweight 10/22 Carbon Fiber rimfire rifle delivers impressive accuracy and control, making it a strong choice for Steel Challenge and beyond.

Year In Review: SSUSA Covers Of 2025

A look back at Shooting Sports USA’s 2025 covers, celebrating championship highlights and marking the final chapter of the digital magazine.

Interests



Get the best of Shooting Sports USA delivered to your inbox.