6mm Rem to 6.5x55 consversion?

[anweis]

If i rebarrel from 6mm Rem to 6.5x55, would i also have to re-work the bolt or the action? The two are very close, but are they close enough that no work is needed? Thanks   

[trotterlg]

My guess is the bolt face may have to be opened a little, other than that it may be an easy swap.  Larry

[kyelkhunter3006]

I was thinking the same thing as the 6.5x55 (as originally designed) has a .480 head vs the U.S. standard of .473 for most of our rounds.  But I've read somewhere (and now I can't find it to save my life) that the U.S. ammo companies have been making the 6.5x55 brass with the .473 diameter for years now, so that it functions in our push feed rifles with out an issue.  So I think that it should work just fine.

[trotterlg]

My experience with brass is that it is considerably smaller than any SAAMI drawings would tell you it should be.  Pick up a piece of brass and see if it will fit your bolt head, the bolt head will be larger than SAAMI specs for it's origional use so it may well work fine with the new one.  Larry

[Davemuzz]

  Pick up a piece of brass and see if it will fit your bolt head,

I wish I would have said that. Even better, I wish I would have thought of saying it when I read the post. You know,....sometimes it's the easiest things that you just overlook.

Yeah, try this first....but I think it should be just fine.

[anweis]

Pick up a piece of brass and see if it will fit your bolt head,

Thank you for all of your replies.
I did try a piece of 6.5x55 brass, and it does fit the bolt face, extractor, and magazine. However, i think that there may be another problem. This is a short action Winchester. The 6mm rounds loaded with 100grain bullets fit perfectly in the magazine, and there is no spare room in the mag, as far as i can tell. I am afraid that the 55mm case loaded with long 140 or 160 grainers would not fit in this magazine.
It may be a wisser and better fitting (in magazine and bolt face) choice to go with the .260 Remington, maybe?

[kyelkhunter3006]

If you reload or know someone who does, have them make up some dummy rounds with the bullets you want to use and see if they fit the mag and cycle ok. 

You're probably right about the mag length though.  I know someone who made up a 6.5x55 on a short action Browning A-bolt specifically to use bullets 130gr and lighter, and none of the factory 140gr loads will fit in the magazine.  That's what kept me from buying it when he decided to sell it.  Call me weird, but on any gun I own, I want the available factory loads to be able to function and fire in it.  There may come a time that you don't have any ammo available other than what you find in the store.  If it doesn't work in your gun, then you're screwed.

I'd imagine that the .260 would work ok, unless you load an extremely long bullet in it.

[Luckyducker]

I have no idea what rifle you are currently have that is chambered in 260Rem, but most factory rifles sport barrels with a twist rate that is too slow to stabilize bullets suitable for the 6.5 Swede.  IIRC, the factory barrels utilize a 1/9" rate of twist which I believe is best with bullets of no heavier/longer than 130 grains.  Every testimony I have heard from 6.5 shooters with 9" twist rifles complain of mundane accuracy with the 140's.  That is why the older Swede Mausers were made with barrels that had a 7.5" twist.  I shoot a 264WinMag with 1/8" twist and it handles the 160's superbly, but another rifle in this caliber I had built with 1/9" twist struggled with accuracy with bullets heavier than 130 grain.   Also, the magazine length of the 260 is too short for the 6.5 Swede cartridges.  That is why customs in this cartridge are built on long actions.  Hate to be the bearer of bad news, but better to have this info before you spend your money.  Good Luck

[Mikey]

Probably not a good idea to try converting the 6mm to a 6.5 Swede.  The 6mm and short action it is used in is too short for the Swede. 

I think the issue of case head diameter is a wash when using American brass.

I think your best bet, if you still intend to use that action, is to convert ot the 260; it's another 308 off-shoot and the same length as the 6mm.  The ballistics of this round are close enough to the Swede.

If you are concerned about rifling and twist then head on down to the silhouette shooters forum and see what they recommend for a twist to stabalize the bullet weight you want.  Mikey.

[Davemuzz]

Well, let me "go against the grain" so-to-speak with my recent Savage rifle that I put together, and you can be the judge.

I purchased a brand new stainless Model 12 action (short action) (Now...the M-12 is a bolt action single shot) with the intent of buying a Shilen 7mm-08. Well, I changed my mind and even with the short action, I ordered a stainless Shilen in 6.5x55 Swede, and I ordered the barrel with a 1-9 twist. In fact, Berger 140 grain VLD bullets recommends that these bullets "be" shot through a 1-9 twist barrel. 

Well, when I load up the 140 Berger's, if i don't fire 'em...when I go to eject them, most are about ten thousands too long (because that's how long I seat 'em) to eject....but I just stick my fat thumb in there and the case then lays in the gun for easy retrieval.  This gun will put 5 Bergers in a half-inch group at 100 yards. RL-22 powder and WRL primers.

I am currently working on shooting a Barnes 120 grain (which clear the short action port with no problems) and here is my first two "outings". So.....You make your decesion from here....but I wouldn't be concerned about a short action and the 1-9 twist??...I would order it if I were to do it again!

[Nobade]

I would suggest 6.5 Creedmoor. Fits in a short action, ballistics about like 260 factory ammo, comes with top notch bullets in factory loadings (unlike 260 which there is no top notch factory ammo available), and so far accuracy has been extremely good. All that Winchester would require is a barrel change.

[Luckyducker]

Anweis, I must have had my brain on standbye when I read your post yesterday.  I thought I read...... oh well it doesn't matter now.  Rebarreling your 6mmRem to 6.5X55 would be OK with a fast rate of twist if your mag box is long enough to handle the Swede cartridges.  You could try some in the box and see how they do and that will tell you the story. 

[anweis]

Let me explain this better:
The 6mm is a fine cartridge, with it's limits. If i could shoot 120 gr. premium copper bullets from it, i would not change it. I am looking for minimal recoil and a rifle that would kill anything in North America.

The twist will be 1:8". I handload.

The 6.5x55 would fit and work, but the 140-160 grainers will have to be all handloaded and fitted deep into the case, for the cartridge to fit the magazine. I tried.
The 51mm case (.260 Rem) would be a better fit.

[Davemuzz]

So put a single shot follower in the magazine and make it a single shot bolt action gun. My Savage Model 12 6.5 Swede is a single shot bolt action gun.

After all, it's so accurate......how many shots do you need?   

Dave