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6BR pressure signs low loads

When I ordered a press I offered my card number for payment, guy says no worries the invoice will be in the box just send a check. :)

They are bushing dies , so you can tune your neck tension to what the rifle wants.
 
SPJ said:
When I ordered a press I offered my card number for payment, guy says no worries the invoice will be in the box just send a check. :)

They are bushing dies , so you can tune your neck tension to what the rifle wants.
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Ahhhh so they can use the Redding bushings?
 
In the past, there has been such an unlikely thing explored, - aptly referred to as a squeeze bore - with a gradual taper to a smaller diameter at the muzzle. While I would expect, with no experience within this hypothetical, - much more severely dramatic effects than what you describe, - if a 5.56 barrel was accidentally chambered for a moderate size 6mm case and with a long free bore, such that it would chamber and fire, would it be possible that with a modest starting charge, there actually wouldn’t be a major malfunction and brass would just “age” at an exceptionally accelerated rate?
 
Not sure if this has already been posted yet but I had the exact same problem with my 6BR and after many many hours of pulling hair out, asking questions and scouring the internet I found the answer. I was not wiping the case lube off the cases good enough and eventually enough lube had also built up on the chamber walls (which I also neglected to clean) that it created major high pressure issues. Many on here with far more knowledge than myself will know what im talking about. Anyway once i swabbed out my chamber real good and used brake clean on my cases after sizing no more problems. I found the answer to my issue on these forums. "Maybe" this is also the original posters problem as well.
 
1sickPuppy said:
Ahhhh so they can use the Redding bushings?
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Harrells dies pretty much same as Redding and use either Redding or Wilson bushings. Is your chamber a Norma chamber or 6BR Remington chamber? 27 gr of Varget is max for 6BR Rem in the Berger book. Also the velocity for that max load with a 105gr bullet as stated in the Berger book is 2656 out of a 24 inch barrel.
Very similar to what you are getting. Do you have reamer print?
 
davidjoe said:
In the past, there has been such an unlikely thing explored, - aptly referred to as a squeeze bore - with a gradual taper to a smaller diameter at the muzzle. While I would expect, with no experience within this hypothetical, - much more severely dramatic effects than what you describe, - if a 5.56 barrel was accidentally chambered for a moderate size 6mm case and with a long free bore, such that it would chamber and fire, would it be possible that with a modest starting charge, there actually wouldn’t be a major malfunction and brass would just “age” at an exceptionally accelerated rate?
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Interesting I do dry the chamber after cleaning the barrel. I use Hoppes barrel blaster.

I also tumble the brass in walnut to remove the imperial wax case lube. Maybe I’ll try the brake cleaner on the brass next time.
 
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Dgd6mm said:
I thought I read in the past where they pick a # die. Is this so or am I thinking of a different company?
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They have I believe 8 different sizes for every chambering they make dies for. They match up your brass to the one that fits it best. The larger the number, the smaller the die is. A D4 is smaller than a D1 for example. PPC, X47, BR, BRA and Dasher. Accept any of the normal size bushings, Redding, Hornady, RCBS, Wilson, whidden. And they include a Hornady lock ring and a brass comparator to measure with. Price is generally as cheap if not cheaper than other options as well.
 
1sickPuppy said:
Interesting I do dry the chamber after cleaning the barrel. I use Hoppes barrel blaster.

I also tumble the brass in walnut to remove the imperial wax case lube. Maybe I’ll try the brake cleaner on the brass next time.
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On the blaster stuff: It's a degreaser that comes out under pressure. Is it possible you're cooling the chamber (the spray will be cold out of the can - release of pressure - plus evaporative cooling as the stuff evaporates) to the point where you're getting condensation?

I tumble for about 20 minutes to remove Imperial (if I don't simply wipe it off.) No need for brake cleaner.
 
divingin said:
On the blaster stuff: It's a degreaser that comes out under pressure. Is it possible you're cooling the chamber (the spray will be cold out of the can - release of pressure - plus evaporative cooling as the stuff evaporates) to the point where you're getting condensation?

I tumble for about 20 minutes to remove Imperial (if I don't simply wipe it off.) No need for brake cleaner.
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Good point, I actually apply the blaster stuff to a patch and swab the chamber. I do the same as you tumble the imperial wax off, not sure how long I leave it in. I toss it in and walk away maybe an hour or so.
 
Guys, do yourselves a favor. Buy a couple of pistol rods (short fixed handle cleaning rods) Put a 22 cal Iosso brush on one and a 40 cal on the other, buy some 3" shotgun patches and some Ronsonol lighter fluid. Soak a patch and run it in your chamber with the 22 brush, twist it around, pull it out and go back in with the 40 cal and you're done. The lighter fluid is a very good cleaner, leaves just enough protectant and the rest evaporates.

I hope you figure out your issues here and just so you know, it shouldn't be this difficult to get a rifle running. Something, somewhere is NOT right. Most any 6BR should run a 105 class bullet 28-2900 without showing overpressure symptoms on Lapua brass given that you have 28" ish barrel, enough neck clearance and your brass is not too long for your chamber. It's been said forever that if your BR won't shoot 30 grains of Varget and a 107 SMK then there's something wrong. (should probably replace that Sierra bullet with another brand by today's standards) but regardless there is something wrong that you might reach out to the builder of the rifle or the barrel manufacturer to figure out. Oh yea, even if you DO have a fast lot of Varget that is the reason behind the pressure symptoms, your velocity would be MUCH higher than what it is. I hope you get it figured out. Good luck.
 
1sickPuppy said:
what does it mean if my bullet won't drop into a fired case freely?
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If a bullet will not freely drop into a fired case that suggests that you need to turn the necks. Not only could it contribute to early pressure, but could result in inconsistent bullet release affecting both grouping and consistency of pressure. I suggest turning the neck of one case to give you a total of 0.004" clearance (0.002" all around) and see if that changes things.

While you are at it, check the case length. If the case mouth is getting into the bevel at the end of the chamber neck that can affect pressure and other things. You may need to trim the case back to have adequate clearance.
 
I tested more loads and the bullet does fall freely into the case necks.

Case length has lots of clearance verified with bore scope.

Brass doesn’t seem to grow after firing and FL resizing.

Cleaned barrel to bare steel and dry chamber, loaded up hotter rounds 29-30.5 gr. 2750-2850. 30 gr seems to be the sweet spot running at 2800 in a 24” barrel.

No marks on brass face.

Is 2800 fps too fast for a 24” barrel?

Now Heavy bolt lift now due to hotter loads is my guess?

What neck tension is ideal?
 
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