Gunsmithing 7mm-08 to 7x57AI ?

[roggom]

Just wondering if it's possible to ream a 7-08 to 7x57 AI. This would be on a tikka so action length is already long and mag length will be an easy changed Just don't know if the AI reamer would clean up without having to set the barrel back. In that case will prob go with a custom bbl.

Sure
There are
Other cartridge out there that would be more efficient but I like the
7x57.

 

[Goatman007]

The X57 is longer than the -08, so should be no problem. As I am a fan of the -08, I have to ask the rhetorical question.......Why??

 

[roggom]

The short answer boils down to preference. I am a long time fan of the 7x57 and have several rifles chambered in such and plenty of brass, dies and factory ammo. I just like the Tikka and the 7x57, so having a Tikka or a Sako in 7x57 would be a win for me.

Sure, there really isn't any argument I can make to justify the 7x57 over the -08 as they are pretty much ballistic twins. It kinda mimics the 308 -06 debate with efficiency and heavy for caliber bullets.

The only reason I mentioned punching to AI was that the -08 is wider in some parts, so even though the 7x57 is longer, this is not as wide around the shoulder and body, so for a 7x57 to be reamed in, the barrel will need to be set back. The AI is just as wide as a -08 and should clean it up, just wanted a Smith to ring in before pursuit of such a project.

It is not that I am recoil shy, as I already have Tikka's in 7mag and -06, but to me the 7x57 and -08 are the prefect ratio of energy/recoil and this seems like something I could use til I am 90 (if I live that long)

In the end I may just go with a Tikka compact or stainless in -08 and call it done.

 

[Ledzep]

It's very close.

The 7-08 shoulder is somewheres around .453" tapering up to .470ish at the web. The 7x57AI shoulder is ~.450", with a taper back to ~.470" at the web. This from data I can find googled.

If everything was perfect (your 7-08 reamer was on the tight side and your 7x57 AI reamer was on the wide side), you could pull it off. However, if things are the other way around, you're going to have an eliptical double tapered mess. Like I said, it's close-- close enough I would set the barrel back just to make sure.

 

[sandwarrior]

LedZep,

I don't know what source of information you are using, but the 7x57AI should be .459" at the shoulder.

roggom,

Yes, the 7mm-08 chamber will clean up to a 7x57AI.

 

[Ledzep]

google images. I think I was looking at cartridge specs, not chambers.

What is the chamber dia. for the 7-08 shoulder?

 

[sandwarrior]

google images. I think I was looking at cartridge specs, not chambers.

What is the chamber dia. for the 7-08 shoulder?

The 7mm-08 is .454"

In most of my reloading books, for quick reference, They show a .455" shoulder for the Ackley cartridges. Not only did Ackley kind of standardize a 40* shoulder, he standardized shoulder width, thus reducing taper (the most useful part of an Ackley, IMO.) I stand corrected on that issue. I'm pretty sure though, the ones I've worked with had a .459" dia. shoulder.

That said a 7mm-08 will still clean up. The 7x57AI will be .200" longer than the 7mm-08 so the point at which the 7mm-08 reaches .454" it will still have that .200" to go, and will be inside the diameter on the 7x57AI.