Larry Koch
Silver $$ Contributor
You might round up a neck turner. PMA makes a good one, the pumpkin is still king, but you could find a used one on this forum that will work until you decide how you want to roll.
6BR Pressure Found Low Charge
- Thread starter MikeG08
- Start date
268 loaded round neck dia. is going into a .269 - .271 neck
So your neck is at least .271 and maybe a hair bigger. That gives you at least .003 clearance. You should be fine on clearance. We need to see a couple pics of the head end of those cases that were hard to open. Need to see them with the fired primer still in them. A good close-up with good focus.
Frank
So your neck is at least .271 and maybe a hair bigger. That gives you at least .003 clearance. You should be fine on clearance. We need to see a couple pics of the head end of those cases that were hard to open. Need to see them with the fired primer still in them. A good close-up with good focus.
Frank
dgeesaman
Gold $$ Contributor
Regarding the dented necks, just use your fingertip to keep the front of the case from pushing out until the bolt is entirely open. Then that fired brass will suitable to check for the bullet slipping cleanly out.
I'd call the smith who chambered this barrel and find out what the reamer neck diameter is. I have a .271 neck and that's as small as I'd ever consider a 'no-turn' neck because some brass is too thick for that. .272-.273 is far more common.
I'd call the smith who chambered this barrel and find out what the reamer neck diameter is. I have a .271 neck and that's as small as I'd ever consider a 'no-turn' neck because some brass is too thick for that. .272-.273 is far more common.
Larry Koch
Silver $$ Contributor
That’s a beautiful thing. Yeah I’ve got nothing like that.
I do run a bore scope every cleaning. I also clean my suppressor after each outing or if less than 50 rds every other. Excessive but I like to keep it clean. I keep the entire barrel bare metal after each outing.
The smith was Alpha and Omega tool in MO. They closed up shop. And unfortunately he is not reachable. Caleb Morris was the one who chambered.
Brass trim is 1.550 with Giraud Trimmer, Bullet is .040" back of Jam
you could be on the ragged edge of too long brass OAL. spec is 155.98 and depending on how the chamber is cut you could be a tad too long??? for as often as you clean there is no downside to being a couple thou short on brass OAL to prevent the brass from jamming into the end of the chamber. your cleaning routine will not allow a carbon ring to form if there were an increased chance. you might try on a few rounds and see if it will make a difference . - not sure what those dents in the case mouth are???? are they in the same location on the case each time???? can you pull one carefully by hand without letting it hit anything to see if the ejector is causing???
stan
That was something I was getting at in my OP. I don't care about speed in this barrel. If I can get in a window at the lower charge and shoot I'm fine with that.
I suppose as long as I'm not getting pressure signs it should be fine?
I sized the brass already. My plan was to keep it separate and use that brass for foulers. I could load a couple at that lower charge where pressure starts if it would be beneficial.
Another member posted on the dent, I will use my finger to keep the case pushed in so it doesn't dent right as its coming out.
What would a good trim length be 1.545"?
yes i think you would be fine with 1.540 or 1.545. there will be no issue with accuracy and with you cleaning regimen a carbon ring will never form and that would be the only downside of slightly short brass. i too am surprised at your seating depth??? most BR cases like to be in the .010 in the lands to .010 jump. you usually find a load within .005 either direction that will remain pretty stable.
stan
ps- i like about .004 into the lands
Last edited:
So when I say jam I’m using Erik Cortina’s method for finding the stuck bullet jam point.
Prep case as normal, seat very long, apply imperial wax to the ojive and chamber the round so that the barrel is seating the bullet further down the neck. I repeated this twice and took the longer of the 2. They were within .002” of each other.
I believe this method likely goes deeper in than just touching?
I have the Hornady tool but not a BR case to measure.
So I loaded up some more rounds this evening and plan to shoot them Sunday. Looks like a lighter wind day.
Loaded up 3rds @27.60 and 3 @27.80. I will shoot these on the same target style as the previous powder ladder.
I loaded 8 foulers @ 28.0.
I also loaded 16@ 28.0 to shoot some more groups to see if the previous groups repeat.
I trimmed all of the cases to 1.545” OAL.
Loaded up 3rds @27.60 and 3 @27.80. I will shoot these on the same target style as the previous powder ladder.
I loaded 8 foulers @ 28.0.
I also loaded 16@ 28.0 to shoot some more groups to see if the previous groups repeat.
I trimmed all of the cases to 1.545” OAL.
what is your chamber length ?? most of mine are 1.570 and most new Lapua brass is 1.555 out of the box and rarely need trimmed--I suspect a donut in those cases that were high pressure--see if a bullet will drop thru the neck --if you have resized them them seat a bullet and measure the neck dia. right at the shoulder junction and see if they are near .271-.272--I think the donut is causing your problem--Roger
Ended up getting out back today. Probably should have waited until tomorrow. The wind was stronger than when I tested last time.
This photo was virgin brass trimmed to 1.545”
28.0gr. The impact to the far right and the left both had heavy bolt lift. The one on the right was very heavy. I took some pictures of the brass as I was out there since the light was so good.
3 of the 5 shots had heavy lift with the one on the right being very heavy. Here are the pieces of brass that were heavy fresh out of the chamber.
I noticed 2 levels of rings around the necks. Are they too short now?
Lol..
This photo was virgin brass trimmed to 1.545”
28.0gr. The impact to the far right and the left both had heavy bolt lift. The one on the right was very heavy. I took some pictures of the brass as I was out there since the light was so good.
3 of the 5 shots had heavy lift with the one on the right being very heavy. Here are the pieces of brass that were heavy fresh out of the chamber.
I noticed 2 levels of rings around the necks. Are they too short now?
Lol..
Attachments
Last edited:
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.