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View Full Version : Interchanging barrels between 7mm08 and 280 Ackley Improved



GPM
12-10-2009, 02:03 AM
First, let me take a moment to thank Jim Briggs - Northlander. He has been tremendously helpful in helping me plan out my build. If you have questions, I highly recommend just giving him a call. He's definitely earned my business.

I am going to build a 7mm08 rifle, primarily for hunting. If possible, I'd also like to be able to switch barrels and get something a little closer to a 7Rem Mag ballistics. However, Jim informed me that these are different bolt head sizes, so it's more complicated than simply switching a barrel.

As I understand him, if I base my build on a long-action .473" (instead of the short action), I should be able to switch between the 7mm08 and the 280 AI with just a barrel. The tradeoff will be an extra 1/2" on the action/rifle length, and a very few ounces of weight.

My questions:

1. Has anyone done this? Care to share your experiences?

2. Are there any issues with feeding? I heard that I should be sure to use the centerfeed-type magazine.

3. Is there any other tradeoff to giving up a short-action for a long-action? Will this affect accuracy in any way?

GPM

GaCop
12-10-2009, 08:49 AM
First, let me take a moment to thank Jim Briggs - Northlander. He has been tremendously helpful in helping me plan out my build. If you have questions, I highly recommend just giving him a call. He's definitely earned my business.

I am going to build a 7mm08 rifle, primarily for hunting. If possible, I'd also like to be able to switch barrels and get something a little closer to a 7Rem Mag ballistics. However, Jim informed me that these are different bolt head sizes, so it's more complicated than simply switching a barrel.

As I understand him, if I base my build on a long-action .473" (instead of the short action), I should be able to switch between the 7mm08 and the 280 AI with just a barrel. The tradeoff will be an extra 1/2" on the action/rifle length, and a very few ounces of weight.

My questions:

1. Has anyone done this? Care to share your experiences?

2. Are there any issues with feeding? I heard that I should be sure to use the centerfeed-type magazine.

3. Is there any other tradeoff to giving up a short-action for a long-action? Will this affect accuracy in any way?

GPM


Answering the last question first, no accuracy difference between SA and LA.

I recently completed a 280AI benchrest build on a 110 action. Other than it's unique headspace gauge, everything was straight forward. I used a stagger feed action with a single shot follower to be able to seat the long 175/180 bullets close to the lands.

Use of a centerfeed action does show better feeding a greater portion of the time. There are rare occasions the feed lips have to be tweeked to improve feeding.

Go for it, you'll love the 280AI. It will come close to the 7mm Rem mag with the lighter bullets.

BrentWin
12-10-2009, 10:47 AM
If you do have to do some tweeking to the mag lips, I would order another mag box. They are lees than $10 and you will have one for the AI and one for the 08.

It will add only about 30 seconds to your barrel change, after you get the hang of it.