Monthly Archives: January 2010

280 Ackley Improved Alert

Author’s Note:  Read the post at this link first, it supersedes this discussion.

http://wp.me/perb6-8L

A few years back Nosler decided to bring the 280 Ackley Improved into their list of custom brass and rifles. In order to do this they wanted to take the 280 AI to SAAMI and have it standardized.

Part of the process of standardizing the cartridge was for Nosler to see if other manufacturers had worked with it. They found that Remington had been chambering the 280 in their custom shop. Now here is where the alert comes in. Remington’s Custom Shop chose to shorten the headspace on the venerable design by .014″. When Nosler sent drawings to SAAMI they picked up that number as well.

So by a vote of the members of SAAMI the commercial established specifications for the 280 Ackley were changed from the original design.  The reason reported for this change is that Remington believed it was necessary in order for factory 280 Remington ammunition to be fireformed safely in an Ackley chamber.  Apparently they did not know that Ackley was the single most successful wildcatter of the 20th century.  While he was not the first guy to create and “improved” design, he was the first to standardize the idea and create a safe method of fireforming factory ammo in improved chambers.

Ackley’s method was simple, he simply used a headspace gauge .004″ shorter than the factory case.  This shorter headspace assured that the cartridge would be held tight between the bolt face and the junction of the neck and shoulder of the chamber during fire forming.  Ackley’s method worked fine for more than 50 years before these alterations to his design were made.

Bottom line for anyone who now works with the 280 Ackley Improved you must decide which version of the chamber you will use; the SAAMI or the Ackley; you cannot safely use the Nosler brass in  a traditional Ackley chamber, although it would still be safe to fire form factory ammo in a SAAMI/Nosler chamber.

Compare the length of these two designs.

UPDATE:  See this post for new information

Here is another article about the 280 Ackley Improved:

 

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Prairie Dogs and Norma Components

At the end of May I was invited to attend a prairie dog shoot in Northern Wyoming, near Devil’s Tower.  Norma was the host for this event and much of the powder burned and other components were supplied by Norma.

Shots were available at just about any range you want.  One pair of shooters were there specifically to shoot long range they were concentrating on the dogs over 500 yards.  The longest confirmed hit was over 1200 yards (don’t laugh, it took a lot of shots to walk that one in.)  The equipment that these boys used is highly specialized.

One of the guns we shot on the hunt was a 6BR Norma.  The Norma designation refers to the specifications of the chamber that are designed for use with Norma Brass.  They clearly are capable of good accuracy.  Richard Folsland is the Reloading Editor for Gun World Magazine, this was his 6mm Norma BR rifle.  He showed us some groups from is load development, ranging from .287″ to .452″ with an average of a little under .400″.

The rifle is a Remington 700 left hand in an HS Precision Stock, McGowen Precision Barrel LLC provided the barrel for this custom rifle.  It was put together as a varmint rifle rather than a BR competition gun, yet it was easily minute of ground squirel out to at least 300 yards.

If you would like to read more about this gun, check out the Novemer 2009, Gun World Magazine.

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