Resizing 6.5x284 to 6x284 Lapua brass, what bushings?

[fishdundee]

I am going to have a 6x284 built and I was looking for info for the bushings I will need to resize the necks. Are you guys stepping it down with one bushing or are you doing it in 2 step? I'll be using lapua brass for this project. Any info is greatly appreciated.

Skol'

 

[DJ Fergus]

I am going to have a 6x284 built and I was looking for info for the bushings I will need to resize the necks. Are you guys stepping it down with one bushing or are you doing it in 2 step? I'll be using lapua brass for this project. Any info is greatly appreciated.

Skol'

Maybe someone will come along who has some experience with this particular cartridge. I do have a 6mm PRC, so I am necking down from 6.5 to 6mm. I can neck down in two steps but I've had better results necking down in 3 steps with brass once fired from a 6.5 chamber. I haven't necked new brass, so maybe two steps would be fine on new brass. My final bushing is .270" but that leaves a bit more tension that I would like. I don't turn necks and neck thickness will make a difference in what bushing size will work best. I've ordered a .275" to give a try. I have a neck mandrel that does size it up after running the neck through the .270" bushing but I think I can run it through the .275" and still be necking up just a little bit with the mandrel. I'm guessing that you will end up needing a bushing somewhere between .270 and .275 for your final step

 

[Dmagna]

Never had a problem necking down from 6.5mm to 6mm in one step. Make sure you load up some dummy ammo for your smith to use to chamber your rifle with. That way he chambers it to the specific brass and bullet.

 

[lancetkenyon]

I step down necks with .020+" in 3 steps, just to eliminate any possible crushing issues. If you are doing 100 cases, this doesn't take any time at all. Just lube the necks. I do 7mm (.284") to 6.5mm (.264") all the time with various wildcat brass like the Sherman Short Mag lines. But for .264" to .257", I do a single pass.

I have done hundreds of 6.5CM to 6CM brass this way. Lapua brass mostly.
.264 (virgin necks are probably .289 OD neck) to .243 (.271 OD neck), remembering necks will thicken going down, I would go:
.283"
.277"
.271"
Then run a .241 mandrel back up through.
Finally, trim and square up the necks and chamfer in/out.

 

[Mikecr]

Couple things about this that I wonder about.
1. Bushings don't usually size the entire length of necks, so how do you get the unsized portion down with bushings?
2. How do you get the neck length from one cal of cartridge to another the same?

 

[can1010]

over the years i have found it easier to use the hornady neck size dies for this, it sizes the whole neck and can go in larger amounts than bushings can. with bushings if you try to size more than .010 you risk crushed shoulders better to do .008 or less and then needing multiple bushings if you can find the sizes you need. the neck die will do this in one step.