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6.5-284 Norma chamber

dixrid2

Plastic
Joined
Apr 25, 2016
Finished chambering a new barrel last night to 6.5-284 Norma. Using a 284 Win. go gauge, had the head space set perfect. I asked the customer to bring 3 dummy rounds with the cases he will be using. He resized new Lapua brass, and threw in 140 gr. Bergers. Checked the headspace with his shells and found that they had about .004 to much headspace. I had left the barrel in the lathe so it was nothing to adjust the headspace to his brass, but now I'm wondering if I did the right thing, or should I have just left it alone with the original headspace from the gauge?
 
I would have left it alone with headspace set properly to the gage. He is likely over sizing his brass. Depending on what your definition of "pefect" was, that chamber may now have problems accepting factory ammo or his reloads should he set his dies up properly. Perfect place to use the Redding competition shellholders to adjust resizing length to the chamber. You do need a couple thou headspace for the rifle to function correctly with all ammo when clean and dirty.
 
Always go by the gage. Ammo max dimension is still smaller than chamber min. Check out the SAAMI web sight for chamber and ammo drawings.
 
most are going to tell you you should have set to min. but ponder this legit question? maybe factory brass was too short .004, how does customer make brass longer to work in even min spec chamber? fireform? or set chamber under min spec, very safe but may not chamber some other factory brass. Ideal? no, but safe? yes. You could split difference between brass and min spec. I would have gotten new brass at least and not resized. And would mark barrel -.004 somewhere, and make customer sign note that they understand fully.
 
There is some difference between Winchester .284 Win brass and Norma .284 brass. Don't know exactly what. You should verify what he is going to use and make clear that they are not the same (my guess is he already knows this.) Set headspace as appropriate using gauges (since you don't know the dimensions of the brass.)
 
I want to change my 6.5x284 norma to a 284 Winchester. Would I be better buying a new barrle or have my 6.5x284 redone, chambered, lands ect... I am looking at cost
 
Find chamber drawings for both cartridges with dimensions and compare. You MAY be able to simply run the Win reamer in and slightly enlarge the Norma chamber. If that won't work, you should be able to set back the barrel a little to get enough meat and rechamber with the Win reamer.

How many rounds does the barrel have on it? If a lot, a new barrel might be the better choice.

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Ignore this; I thought you wanted to go from 6.5-284 Norma to 6.5-284 Win. Going to actual .284 Win will need a .284 barrel.
 
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I had thought that the norma offering was longer in body of the case by a few thousands then the winchester standard wild cat?
 
I want to change my 6.5x284 norma to a 284 Winchester. Would I be better buying a new barrle or have my 6.5x284 redone, chambered, lands ect... I am looking at cost

Having the bore rebored and rifled to .284 will cost more than a new barrel blank. If you actually want a 6.5x.284 Winchester, then set the shoulder back, refit the barrel, and ream to 6.4x284 Winchester. Careful study of the drawings for each cartridge should indicate how far back to move the barrel, but if there is throat wear or faults with the current chamber it may need to be set back further.
 
I want to change my 6.5x284 norma to a 284 Winchester. Would I be better buying a new barrle or have my 6.5x284 redone, chambered, lands ect... I am looking at cost

You are talking about changing from a 6.5mm caliber to 7mm caliber, correct? I don't think there is enough meat for a rebore. I know I couldn't take my 8mm (.323) to .338. Unless your barrel has unique or distinct features such as octogon, integral bases, etc it is usually considered wiser to go with a new barrel rather than rebore.
 
Even though it is a bull barrles, my thoughts are to go with new barrle. 6.5 284 is a hot load so barrle change out will Need to happen 3 times a year. That is why I want to go to a 284 Winchester barrles on my rifle. Thanks for the info
US Military (ret)
 








 
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