7mm-08 rechambered to 280 Rem in a Tikka T-3?

shortaction said:
Since the T-3's are all standard length actions could a person buy a 7mm-08 and have the barrel rechambered to the 280 rem?

Any problems to address other than buying a 270/30-06 Mag?
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Possible but....7mm-08 has much bigger shoulder dia so setback of a barrel needed would be at least 1/2" unles it is rechambered to 280AI then no setback is needed. Also would there be enough "meat" left in front of a chamber? Over all, changing the bolt stop and magazine would make no economical sense in my opinion.
 
The 280 won't clean up the 7-08 shoulder without setting back at least 3/8 of an inch...however it can easily be rechambered to 280 Ackley or 284 Winchester without setting the barrel back,...but I usually set back about .005 just to put the factory stamping under the stock...rechamber and restamp...buy a new 25-06/270/30-06 mag for the 280AI, shorten the bolt stop and you're in business....:)..the 284 might require magazine mods. As far as having enough "meat" ahead of the chamber...I don't think the T3's in WSM's and long magnums have a larger barrel contour.
 
Rembo said:
The 280 won't clean up the 7-08 shoulder without setting back at least 3/8 of an inch...however it can easily be rechambered to 280 Ackley or 284 Winchester without setting the barrel back,...but I usually set back about .005 just to put the factory stamping under the stock...rechamber and restamp...buy a new 25-06/270/30-06 mag for the 280AI, shorten the bolt stop and you're in business....:)..the 284 might require magazine mods. As far as having enough "meat" ahead of the chamber...I don't think the T3's in WSM's and long magnums have a larger barrel contour.
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Wonder how the 280 AI would perform out of the 22 7/16" barrel?
 
Just for the heck of it I slided my locked vernier at .454" over unfired win brand 280Rem case and....belive it or not the jaws stopped 1 AND 3/16" from the case shoulder so if the new chamber is going to clean up the old one then thats is going to be the minimum barrel setback. I knew the setback is going to be more than 3/8" but never expected to be that much.... Yes the 280AI is the only option b/c 284Win has bad (or expensive to fix) feeding issues....
 
captonion said:
Why not just AI the 7mm-08? A Nosler BT 140gr @ 3050fps and 120gr BT @ 3150fps is nothing to sneeze at.
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Yes you are basically right but....It's about efficiency, some people (including me) just hate to waste 1/2" of action lenght with short cartridge. It's like having 22Hornet in full lenght pre 64' Win action ( I saw one once, it looks funny....) or 410 SXS shotgun on 8ga frame.
 
gunrunner8 said:
Just for the heck of it I slided my locked vernier at .454" over unfired win brand 280Rem case and....belive it or not the jaws stopped 1 AND 3/16" from the case shoulder so if the new chamber is going to clean up the old one then thats is going to be the minimum barrel setback. I knew the setback is going to be more than 3/8" but never expected to be that much.... Yes the 280AI is the only option b/c 284Win has bad (or expensive to fix) feeding issues....
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Ok, I am as green as grass on this so if you could help me understand this. I am assuming that the .454" is the chamber size of the shoulder of the 7mm-08? If my assumption is correct then to me you should take the length of the 280 rem 2"minus the 1 3/16" for 13/16" and then subtract that from the length of the 7mm-08 1 1/4" for a set back of around 7/16" - 1/2"?

I am just trying to visualize this as when I looked at the drawings for the brass I thought this would be the problem, but then there was a thread about people chambering 308's in a 30-06 and firing them so I thought I must be mistaken.

I had thought about the 284Win as I have all the dies and brass for it but thought better of it as trying to get it to feed would likely be a problem.
 
Rembo said:
It would probably run 100 fps faster than the std 280 in that barrel....maybe 150 fps faster...I did a 22" 700 Mountain Rifle to 280AI..runs 3100 with a 139 Hornady.
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Really, I thought the performace would drop with the shorter barrel.

Hmmm, now you have me thinking, didn't really want a 280AI as I like to be able to buy a box of shells, but I have the dies and brass for the 280AI all ready! Hmmmm!
 
gunrunner8 said:
Yes you are basically right but....It's about efficiency, some people (including me) just hate to waste 1/2" of action lenght with short cartridge. It's like having 22Hornet in full lenght pre 64' Win action ( I saw one once, it looks funny....) or 410 SXS shotgun on 8ga frame.
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Yes, this sums up my thoughts prefectly, same as a 257 Roberts and the 284win belong in a Model 70 Short Action.
 
shortaction said:
I had thought about the 284Win as I have all the dies and brass for it but thought better of it as trying to get it to feed would likely be a problem.
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Thats where the 7mm-08 AI would work great, and do everything the 284 will.

Here is good point from SuperCub from a 7mmWSM thread. Just switch 7Mag for 280, and 7WSM for 7mm-08 AI. Very good point by Super. Couldn't have said it better myself.

SuperCub said:
I have a 7Mag here. I should get it cut off a bit at the chamber and have it rechambered for 7WSM. Could really seat those bullets out with the longer action and play a bit with it.
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captonion said:
Thats where the 7mm-08 AI would work great, and do everything the 284 will.

Here is good point from SuperCub from a 7mmWSM thread. Just switch 7Mag for 280, and 7WSM for 7mm-08 AI. Very good point by Super. Couldn't have said it better myself.
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Let me see if I am following your train of thought (very bad cold and full of medication so the thinking is reeeaally slow):).

You are saying go with the 7mm-08 AI and have some freebore added and use the long action magazines?
 
The nice thing about using a short action cartridge in a LA rifle, is that you can use long heavy bullets, seat them out nice and far, gaining a bunch of powder capacity in the process, and still be off the lands and fit within the magazine length. That's what these guys are talking about with idea of the LA rifle built around the 7-08AI.
 
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