Author Topic: 6.5x55 Case stretching and head separations  (Read 654 times)

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Offline reddot

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6.5x55 Case stretching and head separations
« on: May 03, 2003, 01:41:14 AM »
:shock: I purchased a used Virgin Valley Custom Guns barrel in 15 3/4" 6.5x55 Swedish Mauser for my Encore pistol.  I fired a factory round in it and used it to set the sizing die.  I smoked the neck and shoulder and turned the die in until it was just a few thousanths of an inch past where contact with the shoulder was made.  Theoretically, this should be really close to the chamber size and not leave much room for backward thrust of the case in relation to the chamber shoulder.  Strangely enough, some empty cases that were fired in the gun will not allow the gun to close when you try to close the gun with them chambered.  I am also getting the the little burnished rings just forward of the head, showing the cases are stretching, and this was cofirmed using a feeler pick.  The load is moderate, 40.5 gr. of IMR-4064 and a Speer 120 SP.  The cases are trimmed and the bullet is not touching the lands, the barrel having a fairly long throat.  What, other than the frame of the gun flexing, could cause this, and has anyone else run into this.  Or am I just missing something, here.  :grin:
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Offline Duffy

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6.5x55 Case stretching and head separations
« Reply #1 on: May 03, 2003, 07:14:15 PM »
Hmmm my 708 is doing basicly the same thing, I have to resize them to get them to rechamber but am not getting the stretching you speak of. When I resize it only touches the top of the case by the shoulder and the area ahead of the web. I tried rotating the case in the chamber and found that it's a bit out of round. When you hit the right spot it will close but it's tight. Try marking a case, firing it  and rechambering it in the same place to see if it will close then rotate it 180deg and see if theres any difference in closing. Just a thought.

Offline Double D

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6.5x55 Case stretching and head separations
« Reply #2 on: May 04, 2003, 01:34:50 AM »
Three things to need to be done for proper setup and  resize in TC single shots.

First take a file and cut a small notch in the rim.   Each time you put the case in the chamber orient that notch to the same position.   You can align the notch with the edge of the extractor or do as i did file a light mark at 12 o'clock on the breech end of the barel above the chamber.  Don't punch a mark, you can move metal and add problems.


Second, to properly adjust the sizing die for a TC single shot, back the die out of the press a couple of turns. Size a fired case and then chamber and try to close the action. Slowly turn the die a 1/4 turn at a time and keep sizing and trying the brass until it takes sharpsnap to to close the action.  lock the die at this point.  TC used to include these instructions with their loading dies.



Third never use once fired brass in your TC single shot, always start with new.

Offline Mikey

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Stretching cases
« Reply #3 on: May 08, 2003, 04:07:01 AM »
redot:  Which brand of cases or brass are you using?  With the mil-surp calibers, some of the ammunition that is available today is new manufacture but due to the lower costs to make it attractive, the brass is  often not strong enough for reloading and stretches noticeably.  A friend's M38 6.5 Swede did the same thing with Sellier and Bellot ammo.  So, he shoots that stuff once and reloads other brands of cases.  S&B ammo in pistol calibers seems OK for reloading but some of the rifle stuff, especially the 6.5 Swede and the 303 Brit from S&B, don't seem to be strong enough to reload.  You may wish to try another brand of brass if you are using the S&B for reloading.  Hope this helps.  Mikey.

Offline Double D

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6.5x55 Case stretching and head separations
« Reply #4 on: May 08, 2003, 05:18:42 AM »
I haven't noticed the the S&B brass was weaker, but the loads were distinctly  hotter and higher pressure. It's sporting ammo. Showed across the chronograph and showed in the shooting. Fired some Swede S&B in my M95 and had to use a mallet to open the bolt. You could see the extractor cut in the head.  The web also appeared stressed. Fired just fine in a Winchester M-70, but kicked like a mule (fairly it was a featherweight), and extremely accurate for a factory load!.

There is a lot more leeway in a battle rifle chamber than in a sporter, so it should be.  Don't want a tight sporting chamber getting a little dust and dirt in it when the uglies are about to get you.  On the other hand sporting ammo such as the S&B in a military chamber, even in a fine Swede chamber has a good chance to stretch and can get sticky coming out.  That is why GI brass is usually heavier.

In the U.S. there is a tendency to load factory ammo for the weakest, sloppiest action available.  Europeans load sporting ammo for sporting rifles and GI ammo for GI rifles.  S&B is sporting ammo, even FMJ's.

Seems that every generation of shooters rediscover this.  (Darn, I'm starting to sound like those O.F.'s who tried to tell me this 30 years ago. They were all wet then, and oh so right today)