Significant increase in seating pressure..... why?

[Mikemontminy]

What is a norm for brass life in a 284 used in f class?
This is a new clambering for me.

I have shot a dasher for the last 2 years which is my only real experience with guns that will shoot small....... love my Dasher.
CW

I am shooting the 180 Berger hybrids, don’t recall FB but is is such that the bearing surface/boattail junction is well above the darn donut.
I was having all kinds of trouble with vertical with this rifle until I tested neck clearance. That proved to be very helpful. With .0045 or more clearance the vertical went away.
Interesting, .003 clearance if you you only looked at group size


This brass has 4 firings and has not been annealed.

I turned them again after the second firing. Yes the donut area was the thick spot for sure.
CW

I anneal every time and then resize. I also have expander mandrels which are turned down. I use these to adjust neck tension and push out donuts but it doesn’t always work on pushing the donuts to the outside. This can be checked with a drill guage. They can be purchased for around $3.00 shipped. They come in half thousand increments. I will use one that is a half thousand under resized case neck size to look for donut before reloading. If the donut is still there I use a K&M carbide cutter for neck turning in a drill and use this to remove donut. Then recheck with drill guage. You will find that by doing this your neck tension will be very consistent when seating a bullet. This will also make your finished case length very consistent.

 

[Mulligan]

I anneal every time and then resize. I also have expander mandrels which are turned down. I use these to adjust neck tension and push out donuts but it doesn’t always work on pushing the donuts to the outside. This can be checked with a drill guage. They can be purchased for around $3.00 shipped. They come in half thousand increments. I will use one that is a half thousand under resized case neck size to look for donut before reloading. If the donut is still there I use a K&M carbide cutter for neck turning in a drill and use this to remove donut. Then recheck with drill guage. You will find that by doing this your neck tension will be very consistent when seating a bullet. This will also make your finished case length very consistent.

OK, good stuff.
Question, is it worth using Lapua Brass for the .284?
I am new to the caliber and just went with it as i consider it a bit superior. If the folks using Norma brass are not having this issue and are winning, why am i screwing around with necking up Lapua Brass?
CW

 

[Ringostar]

Are you running a tight neck?
if accuracy allows, a no turn would be way better. Turning is time spent in the loading room and not shooting.
CW

My last 2 barrels have both been a .317 neck. Just a light clean up with the neck turner, to catch any thick spots. Anneal every other firing. Whidden full length bushing die, with a .310 bushing sizing half the neck. I also have a Lee 7x57 collet die that will work on 284 cases.

 

[Ringostar]

OK, good stuff.
Question, is it worth using Lapua Brass for the .284?
I am new to the caliber and just went with it as i consider it a bit superior. If the folks using Norma brass are not having this issue and are winning, why am i screwing around with necking up Lapua Brass?
CW

I haven't tried the Norma brass, but heard bad reports of only getting 3-4 firings before the primers were loose. I don't know how hot these people were pushing them though.

 

[Mulligan]

Clay,

Did you happen to forget to brush the inside?

Tom

Tom,
I admit I did not brush. Didn’t think it is needed when pushing that mandral through the neck???

CW

 

[Mulligan]

Size a couple exactly like you did. Brush one before seating, and don't brush the other. Report back the seating force. I think you will find it significantly different. You will even see different results switching brands of brushes if you want to experiment with a third case. I'd bet that's your answer.

Tom

Tom, i think you nailed it!
Thanks
CW

 

[243winxb]

I Brush with RCBS nylon brush and their lube. Bullets seat a lot easier. No expander used. Bushing die.

If ammo is going to sit a while, i hope the lube stops cold welding.