Home Forums Hunting & Shooting Gunsmithing Question on 6.5X55 reamer dimension

Cartridge drawings for the 6.5X55 show the case head to be .479" or .480". I am told that all American brass for this has .473" case heads, and the sample Winchester brass I have bears this out.

What dimensions do your reamers cut - .480" or .473"? Or can you get one or the other?

Also, what kind of throat do your reamers cut? The Swede is one of those like the 7mm Mauser that traditionally had a long throat to allow for those 160 grain military bullets but I was wondering (hoping) if modern made reamers would cut shorter throats for the more popular 120 and 140 grain bullets of today.

Jim
My Henriksen reamer is setup for Lapua (.480) cases with relatively short throat. I don't have my notes in front of me, but it lets Berger 140 VLD's seat out at 3.080+- and 120 Nosler Ballistic Tips seatout at about 2.9 +-. I can check and get back to later after I look at the reamer print. Heading into town in a bit.

I would get a piece of brass and seat the bullet you plan to use at the seating depth you want and tell your reamer guy to duplicate it. I just checked a couple 308 Remington bolts and they measure .485. My 6.5x55 Lapua brass measures .478.
Butch

Jim in Idaho

I use the Lapua and have the 480 case head.

I just went through this exercise with my CZ550. The standard throat was long enough for the heaviest bullets, with all the jump I could not get it to group on 130's at all.

So I worked with a smith in Colorado Springs, Earl Hickman, www.hickmanrifles.com/ -great smith by the way. I had JGS make me a reamer and I very specifically had the throat shortened. Earl gave me advice on the blue print dimensions and we tweaked them a couple of times. I have a 1 in 9 twist on my 550 so its perfect for 130's, not really fast enough for even a 140.

Took it out last week and honestly got a 2 inch square at 200 yards with 5 consecutive rounds. I am working up a load that was suggested by WildAlaska using RL22. So I think it will do even better when I fine tune.

Earl owns reamer and will ream your barrel.

If you want a copy of the print let me know.

My reamer is a stock Clymer I purchased a few years ago. After doing three short chambered barrels, I sent it back to Clymer and had the throat totally removed.

I now throat with Clymer 264 throater with a brass stop collar on it. I throat it as well as my 6.5-06 withch I had the same thing done to to seat a 140 grain Nosler Partition seadted to the base of the throat. If anything make it a bit short: throats only get longer.

Jim, I thought they used the same basic brass for the 6.5x55 as the 30-06 etc in the USA, but most american brass measures .468 or .469 while American Swede cases go .473 so it is slightly larger in reality. My Lapua measures .479, best brass there is by the way...

That begs the question why did our domestic brass makers switch out the dimensions? Surely they must know of the bazillion rifles in existence with the "correct" chamber dimensions? Are currently manufactured rifles chambered to the "new" dimensions? My 25 year old M70 Fwt has original dimensions, including a looong throat, but it shoots lighter bullets just fine. I don't get great case life with domestic brass though, for obvious reasons, so it's Lapua and an old stash of Norma brass for me.

Butch's recommendation is spot on IMO.

Not sure on current rifles, but my 700 Classic (1994) has the original dimensions too. Ditto on case for me too...

How can you shorten the throat using a cutting tool of any kind?

Talking a barrel set-forward by .006 at minimum and then a recut chamber. If Rem 700 or other bolt that recesses within barrel might have to ream the recess deeper as well. Not a big deal with a straight pushfeed type bolt that just clears contact with barrel.

Costs some pretty good coin to pull barrel, set-forward and rechamber if going to index barrel markings etc. Probably better off with a custom barrel job; not like Rem 700 or (I expect) a CZ barrel is any comparison to a custom. Can't overcome the absence of twist either...

The Nosler 140 bthp has longer ogive position than the Sierra; I've compared them and decided to shoot them rather than Sierra in my Win 70. The 160gr Hornady might be a good choice for a Swedish military cut chamber. Also might think about the Lee Custom 170gr mold that MidSouth sells... Slower twist usually favors a cast boolit.