284 win chamber

[Steve Blair]

Dennis,

What water capacity are you using for cases? The 66.0 default QuickLOAD capacity is probably a little low. My Winchester cases are 68.4. Also, what seating depth are you using? I seat Berger 180 Hybrids at 3.265, -.010.

 

[Erik Cortina]

I used the 66.0 gr. H2O capacity, with the 162 AMax seated at a COAL of 3.150" with a 27" barrel. 59.5 gr. of N560 show 3067 fps. 63,339 psi. in 70 degree temperature and 106.2% case fill ratio.

 

[katur83]

Thanks allot Erik

Now I have a place to start, so I start at 56 gr and work my way up, judging by the quick load numbers the N560 seams to be a good fit for the .284 win cartridge I use N560 in all my loads for the 6mm-284 and I get good accuracy and very good speed. I just hope I can get a good load at 2900fps+ with the 162 amax, than I am happy.

Erik and sleepygator can I ask you a quick question?
Do you have a .284 win and if you do are you running a tight neck chamber and neck turning? This is the only thing left for me to decide in my build. I am thinking it might be a good time for me to start learning how to neck turn

 

[Steve Blair]

Erik has a Shehane but I have a straight .284. He may also have a .284. Top shooters often have more rifles than they can remember.

My PT&G reamer is ground for a .313 neck. That is set for a .0125 wall and .004 diametral clearance. I use Winchester brass and it is only a light neck turn. My preferred powders are H4831 SC, Reloder 22 and IMR 7828 SSC, all with Berger 180 Hybrids.

 

[Erik Cortina]

Like sleepygator said, I have a Shehane. I also run a .313" neck, I turn my Lapua brass down and my loaded round measures .309" allowing me .004" clearance.

I think you need to neck turn for max accuracy and consistency.

I don't have a .284 Win, but I might be giving up my Shehane in favor of a .284 win. The Shehane is an awesome round, but since I'm building a magnum I think they will be too close to each other in performance, so I would build a .284 and shoot 162 AMax out of it, I think it would fit nicely between my 6.5x47 Lapua and my 7mm FCM in performance will less recoil than the .284 Shehane with 180's.

So, keep us informed on your build, since I'm also thinking about the exact same build! Oh, and I would also run N560 through it!

 

[dennisinaz]

I am using 3.1" COL. If I add 59 grains, I get 67,000 PSI; can you really get 59 grains in there?

If it is really this good, I am junking this 7WSM as the extra 11 grains actually hurt you!

 

[Erik Cortina]

I am using 3.1" COL. If I add 59 grains, I get 67,000 PSI; can you really get 59 grains in there?

If it is really this good, I am junking this 7WSM as the extra 11 grains actually hurt you!

I don't know what parameters you are using, but here is a screenshot of a .284 Win. with 162 gr. AMax and N560 with a COAL of 3.150"

 

[ThunderDownUnder]

As to the last postings by katur83 and ThunderDownUnder I would just say this (with my respect to both of you):

1. For me, part of accuracy is about pinning down, and removing from the equation, issues that can sabotage accuracy. Donuts are an issue - well known to be a potential saboteur to accuracy.

2. One thing is for sure, the chamber design cannot make a donut in brass disappear. If you ask me could I design a reamer that might help to mitigate the effects of a brass donut, I would say "yes", but could I guarantee that it would not permit the donut to present an accuracy problem at some point on some shot, I would say "no". The one thing I know with the 284 Win donuts based on necked up Lapua 6.5x284 brass is that they are not consistent case to case, with some being rather small, but some being very thick and heavy, and therein lies part of the problem for consistency. If you have an expander ball on your resize die, it will slip through that area on some cases with little back pressure, but on others there will be a great deal of back pressure. When you neck turn, on some cases not a lot of brass is removed in that area, but on others a whole lot of brass comes off in that area.

3. Assumptions or speculations are just that, they may be true or they may be false. I will not speculate what Dave Kiff made up for you (Ian), or make assumptions whether Charles Ballard neck turns, neck reams, does nothing or has a chamber that somewhat works around the donut. It seems to me if no one specifically discussed this donut issue when a reamer was ordered then we are all making assumptions or speculations that may not be quite correct (i.e. that the reamer somehow made provisions to minimize to potential effects of the brass donut).

4. One way to try to mitigate that issue in a chamber design would be to stick a big radius at the junction of the neck and shoulder of the chamber (like a .125" radius), but then you just may have taken one step forward to go two backward, since re-size dies (Redding dies for one) do not have a radius at the junction of the neck and shoulder and what you then get is the brass gets blown out there when fired, only to be crimped way back in when re-sized, and concentricity of the loaded round can suffer with such a set up. It's the total package from my perspective, everything working together to deliver optimum results - the brass, the chamber design, the dies used, etc..

Robert Whitley

Thanks Robert, you were right on and I'm now the wiser for having listened to you!
No outward signs of a donut but after reading your comments and 5 firings on some cases I tried pushing a projectile past the neck shoulder junction. I found there was an increase in pressure needed to push the bullet past the junction that indicated a donut.

I use a no-neck turn chamber and will now inside ream all my fire formed cases to prevent the donuts from forming. Good advice, thanks again Robert.

Ian

 

[BulletShooter]

I have a 284 win and I just got some 6.5-284 Lapus brass and necked them up. I used a sinclare 270 neck EXPENDER then a 284 Expender no neck ring at all. I have found that if one can stay with in .012-.013 as you go up on Expenders no rings.
True they may be thicker at the neck but" there is no ring at all and I lubed the necks on every one.
I did the same thing with a 6 BR brase I made my own Expander's no rings. Sometimes people just get in a hurry,and to if one is going to turn necks it's not a big deal to have a ring because turning takes it off.

 

[FroggyOne2]

My current load with the .284 is Winchester brass, 49.0 grs of RL17 with the Sierra 175's. Vol is 2830 average. Elevation at 1K is 4 inches. I turn the necks to 310, size to 309, uniform the primer pockets, ream the flash hole, deburr the flash hole and I am trimming the cases to 2.145. Seat the bullet just above the neck shoulder joint and let em fly! I also load and shoot the brass from the heaviest to the lightest.

 

[FroggyOne2]

Also would like to add that two of my friends whom also are shooting the .284 are both using 52.0 grs of N160 and it shoots lights out. They both are in the 2830 range.

 

[AWLEAPHART]

When the .284 articles/fourm topics started up I had to have one. So I had one build, and after the fact I didn't think it was going to shoot well because of the reamer that was used.
162 AMAX,OAL 3.21 and my neck chamber is .321, loaded round neck .312 Laupa brass.(0.09)
54G H4350 @ approx: 2850 will get me under an inch @ 500 yards. The rifle does not like to be pushed as in pressure. If I go to 54.5G of H4350 my groups open up alot.

 

[FroggyOne2]

In my .284 I can't even get pass 51.6 grs of H4350 before hitting pressure. That load is right at the top. I am currently using 49.0 grs of RL17 and suspect that I will have to reduce that when the temp gets warmer.

 

[TonyR]

You might also want to try IMR7828SSC. I have been able to load it beyond where H4350 and H4831SC have given me pressure signs. Mine is a Shehane so my loads would not be helpful but those powders should work fine in the 284 Win as well.

 

[FroggyOne2]

You know Tony, I have thought about that powder, but I will wait till I rebarrel this one to try it. It is a lil too late this year to go changing things now.

 

[Steve Blair]

7828SSC works well for me in a straight .284. The only notable aspects are that it likes to be near full pressure and seems to have a narrow accuracy window. Good velocity, though.

 

[HPMike800]

Erik:
What's a 7mmFCM?

 

[Erik Cortina]

It's a wildcat based on the 7mm WSM, I pushed the shoulder back and ended up with about the same capacity as the 7mm RSAUM but with a 35* shoulder, a longer neck and better brass options.
Here is the 7mm FCM next to a piece of Norma 270 WSM brass.

 

[FroggyOne2]

Looks pretty slick.

 

[TonyR]

You know Tony, I have thought about that powder, but I will wait till I rebarrel this one to try it. It is a lil too late this year to go changing things now.

Froggy.
Waiting for the next barrel before trying the IMR7828SSC is an excellent idea. I have found widely varying speeds in my 284 Shehane barrels, in some cases 70 fps for the same bullet/powder combo. The most attractive thing about the 7828SSC could be that it may let you get to a velocity node that you couldn't get to with H4831SC without uncomfortable pressures. That's how I found it myself. I started off with H4831SC and started to get pressure signs before I got to 2900 fps. 7828SSC got me there with no problems. I've probably burned 20# of the stuff in competition and it has behaved well in a wide range of match conditions. So just keep it in mind if your next barrel is on the slow side.