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New Lapua 6br brass so tight bullet won't seat even after expander

Lapua is known to come with over tight case necks (6mm BR, .260 Rem, .243, 7mm-08 in my experience). I dry lube the neck with graphite and expand with the appropriate Sinclair mandrel as the first step with a virgin case.
 
This is the reason that I have a fireform barrel and fireform without a bullet.

Yes. I've fireformed using 16 grains of Red Dot at times an 15 grains of Universal Clays over tissue paper. It worked well but never seemed to get the shoulders as sharp as forming with a bullet.

Is there a trick to it?
 
Measure your expander in the die

Sorry for all the delays! But I seldom communicate in this manner and struggle, greatly at times.

The mandrel/expander ball in the Redding die reads .225.

(This is another very good thought as I will be contacting others in the club having them measure as well.)
 
Lapua is known to come with over tight case necks (6mm BR, .260 Rem, .243, 7mm-08 in my experience). I dry lube the neck with graphite and expand with the appropriate Sinclair mandrel as the first step with a virgin case.

More than ever I'm convinced the expander die/mandrel is the answer. I didn't order dry lube along with the die/mandrel, but will get some locally.
 
The mandrel/expander ball in the Redding die reads .225.

Um, your die’s for 22BR maybe?

(Or you’re using a 6BR die with a .225” dia. mandrel?)

May be why that 6BR brass is giving you fits?

What’s the rifle chambered for that you’re loading ammunition to shoot in?
 
As an update: This morning, at the range, I'd given a couple pieces of brass to two knowledgeable shooters who said they'd mic them for neck wall thickness when they got home. I haven't heard from them, but the friend who I gave a few brass to on Thursday had left an email this morning saying he couldn't get them to seat in his Sinclair/Wilson Micro Dies either using the arbor press.

As those here have said sometimes you just get brass that extra tight. In any case, I'm convinced those who suggested the expander die/mandrel are right on. Whether thick necks or tight tolerance the expander thought will take care of it.

I will follow-up after the "stuff" gets here and others mic the brass and let those on this post who have helped know the results.

Thanks to everyone!

(spclark, sorry I didn't include the information you requested in your post. I'm old and simply overlooked it. In answer to your question(s):
The rifle is chambered for a 6 Dasher. I had Kelbly's ream 2 barrels. The existing barrel for a dedicated fireform barrel and a new Krieger 28" #15 Contour (should have gone a little heavier) 1:8 twist, .237 4 groove, .030 Freebore, .2705 Neck. Both barrels reamed with the same new reamer I purchased (JGS "6 Dasher BB"). While I'll try several loads/bullets, my intent is to shoot Berger VLDs Hunting in 105 grain. Hopefully, this will work well from 600 to 1000 on a calm day.)
 
Um, your die’s for 22BR maybe?

(Or you’re using a 6BR die with a .225” dia. mandrel?)

May be why that 6BR brass is giving you fits?

What’s the rifle chambered for that you’re loading ammunition to shoot in?

SPCLARK please see the answer to your questions in my previous post. Thanks!
 
Glad we found your issue

Thanks to you and the others! It's great when you find the issue, but it's great+ when a solution is also added. To get both in such a short time is rare indeed.

I will definitely follow-up with an overview after using the mandrel. I am convinced this will do it. However, in any case, I really appreciate all the help in the matter. I slept much better last night:).
 
or maybe he’s got some .257 bullets by mistake?

Another good thought. However, I'm using Berger 105's and I mic up and separate by length/weight. They're pretty much right-on.

It seems more-and-more this batch of Lapua brass simply have way overly tight necks and a mandrel will cure this.
 
Do you have another redding 6mm die of any other caliber like a 243 or something? Put that expander in there until redding gets you the correct one. This appears to be the culprit and theres no need to keep measuring other stuff until you get the correct expander to start
 
Do you have another redding 6mm die of any other caliber like a 243 or something? Put that expander in there until redding gets you the correct one. This appears to be the culprit and theres no need to keep measuring other stuff until you get the correct expander to start

Another outstanding thought that could get me to this afternoon's shoot!

Yes. I have a 243 and will give the expander a try. Thanks!
 
If his die is necking down that far for a .224 button to work,and now uses a .243 to neck up that sure seems like over working the brass for no reason.
 
Do you have another redding 6mm die of any other caliber like a 243 or something? Put that expander in there until redding gets you the correct one. This appears to be the culprit and theres no need to keep measuring other stuff until you get the correct expander to start

Dusty, just pulled the expander stem from the 243 die and the ball measured .241 as compared to the .225 ball measured from the 6 Dasher Redding die. But when I measured the length of the taper of the stem to the largest point (.241) it exceeded the length of the entire 6mm case by nearly .025. In short, when I put the 243 stem (.241 ball) in the 6br case it came up short of going into the neck as it bottomed out a quarter inch short of entry to the neck.

It was a hell-of-a thought though! Thanks!
 

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