question on chambering 6x47 Lapua

P

pinzmann

Guest
OK, I just chambered a barrel with a new PTG 6x47 Lapua reamer. I used a 6.5x47 headspace gauge. When I set it to the Go gauge, I tried a piece of brass resized with a Forester resizing die. Would not chamber. So I chambered 2-3 thou deeper. Now the brass will chamber but so will my no-go gauge. Is this going to be a problem? Should I go back and take a couple thou off the shoulder of the barrel ? Is there any options with the brass? This is my first attempt at chambering a non-standard caliber.
 
Well since it is not a cartridge with factory loaded ammunition you could use it the way you have it. But if it were my rifle ( and I do own two 30x47's) I would shorten the chamber till the no-go gauge does not go. Then I would push the shoulder of the brass back the couple thousandths needed with the sizing die. The brass should be a crush fit anyhow put the chamber back where it goes and try simply lubing your bolt lugs real well and forcing handle closed with the palm of your hand. If that does not do it crank the sizing die down till shoulder is moved back just enough .
Dick
 
Sounds like your chamber and sizing die do not match, not uncommon at all when you are chambering for non-SAAMI cartridges that only have a couple of thousants where the SAAMI has about 0.008" between maximum chamber and minimum cartridge. The bottom line will be how a case extracts after it is fired in that chamber, resized in that die, and fired again.
 
Just to make sure, is this rifle for you, or someone else. If for someone else, I'd make sure the no-go gauge won't close (if you're using CIP/SAAMI 6.5x47 Lapua gauges). For legal reasons, not technical.

If it s for yourself, I vote with the guys who say chamber for a crush fit on the brass when initially fireforming.

If everything else works out, maybe better do this by cutting the chamber & not setting the case shoulder back with a die. It would only be a couple thousandths, and with small things, brass has a memory. I'd bet you'd have cases that required FL sizing with every firing. Which is OK, but...
 
Probably just the differences in the radius at the shoulder-neck junction. Work to the go gage and if needed take a few thousandths off the bottom of the die. During initial sizing make sure your press has no spring in it. Most do. You can screw the sizing die down to touch the shellholder but under a load the press springs leaving a gap between the shellholder and the die. If that is happening just adjust your die down until that gap disappears.

Dave
 
I went ahead and took off about 1.5 thou from the shoulder and now it won't close on a no-go gauge. Also I resized a new piece of brass to check. Somewhere I had read that it was best to use a fired piece of 6.5x47 brass. That idea didn't work out well. Using resized new brass seems better. All is good now.
And Dave your right about the radius in the neck. I took my original brass and blue-dyked it. The rub mark is right at that junction.
 
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