The 450B in the new Sierra manual edition #6
Posted: Mon Jul 15, 2019 10:43 am
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Part 1 of 3 parts
A copy of the new Sierra manual, Rifle and Handgun Reloading Data, Sixth Edition, Ⓒ 2019, arrived here last week. It includes four pages of reloading data for the 450 Bushmaster. With this publication, Sierra is now part of the too-short list of reliable and reputable firms that have produced 450B reloading data based on tests using SAAMI procedures. The others of which I'm aware are Hodgdon, Hornady, Lyman, and Western Powders.
I can find no mention of the new manual on this website, so here are some initial impressions.
This new manual was overdue -- my copy of their fifth edition has a copyright date of 2003. (In this interval, Hornady produced four manuals, #7 through #10.) However, the Sierra #6 is imposing chunk of print with 1368 numbered pages, an increase of more than 200 pages from the previous edition. Like the fifth edition, the new sixth is published as a 3-ring loose-leaf notebook. The rings are D-shaped so that pages lie flat when the book is opened to any page. Pages measure about 5-1/4 by 8-1/4 inches. There are 10 chapters in the book, separated with tabbed dividers.
Chapter 5, "Rifle Reloading Data", with 760 pages represents better than half the entire manual. Loading data are included for more than 100 different cartridges. I compared data for several cartridges represented in both the fifth and sixth editions. As far as I could determine, the loads shown in this chapter are all new, which indicates this chapter is based on a humongous number of lab determinations of velocity and pressure.
Chapter 8, "Rifle Legacy Reloading Data", consists of 96 pages of additional rifle loading data. It covers 24 rifle cartridges that currently are not very fashionable, with their reloading data being reprinted from the fifth edition. Having it available in the sixth edition will be handy, particularly if you don't have a copy of the fifth edition.
The 4-page section on the 450B cartridge includes a full page of introductory information about cartridge characteristics. It also indicates that Sierra's tests of velocity and pressure for the cartridge were carried out with a universal receiver using a 24-inch barrel with a twist rate of 1-turn in 20 inches. Starline cases were used in the tests, primed with WSR primers. Since the Sierra lab adhered to SAAMI protocols, none of the listed loads should exceed the published SAAMI upper limits.
The introduction also includes a clearly explained and proper warning about the dangers of using a heavy roll crimp on the bullets.
The reloading data are presented in the usual Sierra and Hornady format. Most readers are probably familiar with the format, but just in case, here's a sample from another cartridge:
As with previous editions an "Accuracy Load" and a "Hunting Load" are listed for each bullet in the 450B section, derived from their test data.
Chapter 4, "Reloading", is a fine introduction to reloading tools, techniques, and processes. It's also good reading for reloaders with some experience. Sierra gurus have a stake in furnishing proper instruction--they really want you to avoid errors so that you avoid potentially fatal mishaps and continue to buy lots of Sierra bullets.
(continued in next post
Part 1 of 3 parts
A copy of the new Sierra manual, Rifle and Handgun Reloading Data, Sixth Edition, Ⓒ 2019, arrived here last week. It includes four pages of reloading data for the 450 Bushmaster. With this publication, Sierra is now part of the too-short list of reliable and reputable firms that have produced 450B reloading data based on tests using SAAMI procedures. The others of which I'm aware are Hodgdon, Hornady, Lyman, and Western Powders.
I can find no mention of the new manual on this website, so here are some initial impressions.
This new manual was overdue -- my copy of their fifth edition has a copyright date of 2003. (In this interval, Hornady produced four manuals, #7 through #10.) However, the Sierra #6 is imposing chunk of print with 1368 numbered pages, an increase of more than 200 pages from the previous edition. Like the fifth edition, the new sixth is published as a 3-ring loose-leaf notebook. The rings are D-shaped so that pages lie flat when the book is opened to any page. Pages measure about 5-1/4 by 8-1/4 inches. There are 10 chapters in the book, separated with tabbed dividers.
Chapter 5, "Rifle Reloading Data", with 760 pages represents better than half the entire manual. Loading data are included for more than 100 different cartridges. I compared data for several cartridges represented in both the fifth and sixth editions. As far as I could determine, the loads shown in this chapter are all new, which indicates this chapter is based on a humongous number of lab determinations of velocity and pressure.
Chapter 8, "Rifle Legacy Reloading Data", consists of 96 pages of additional rifle loading data. It covers 24 rifle cartridges that currently are not very fashionable, with their reloading data being reprinted from the fifth edition. Having it available in the sixth edition will be handy, particularly if you don't have a copy of the fifth edition.
The 4-page section on the 450B cartridge includes a full page of introductory information about cartridge characteristics. It also indicates that Sierra's tests of velocity and pressure for the cartridge were carried out with a universal receiver using a 24-inch barrel with a twist rate of 1-turn in 20 inches. Starline cases were used in the tests, primed with WSR primers. Since the Sierra lab adhered to SAAMI protocols, none of the listed loads should exceed the published SAAMI upper limits.
The introduction also includes a clearly explained and proper warning about the dangers of using a heavy roll crimp on the bullets.
The reloading data are presented in the usual Sierra and Hornady format. Most readers are probably familiar with the format, but just in case, here's a sample from another cartridge:
As with previous editions an "Accuracy Load" and a "Hunting Load" are listed for each bullet in the 450B section, derived from their test data.
Chapter 4, "Reloading", is a fine introduction to reloading tools, techniques, and processes. It's also good reading for reloaders with some experience. Sierra gurus have a stake in furnishing proper instruction--they really want you to avoid errors so that you avoid potentially fatal mishaps and continue to buy lots of Sierra bullets.
(continued in next post