"Straight .284", Brass, And Chambering

[CarlGeorge]

In another thread I described a new build I'm in the process of defining. Up until yesterday I was planning on going with a 6.5 Creedmoor. But after speaking with with the gunsmith likely to do the work, along with a close friend who is deeply involved in long range F Open shooting, the Straight .284 is now under consideration.

I've done a good bit of Googling and reading, but I have some really fundamental questions.

1. What is the nature of the term "Straight .284"? Is that used to mean "regular" or "standard" or "unadulterated" .284 Win? "The original .284" if you will?
2. I've read of the (lack of) availability of .284 brass - and how people take Lapua 6.5-284 and neck it up to .284. Can that neck up be done in one step - using a .284 mandrel on the .264 out-of-the-box Lapua brass?
3. My understanding is a reamer with a slightly-larger-than-spec neck needs to be used in order to accommodate the necked-up Lapua brass. (I saw one post that even referred to them as a .284 Win reamer and a .284 Lapua reamer.) I'll obviously have a conversation with the gunsmith about this, but for gunsmiths that typically do work for this class of rig (this guy does a ton of F-Class building), is it typical for them to have this slightly larger .284 reamer? Or is that another wrinkle I'll need to navigate?

On a more general note, I'm not a fan of recoil. LOL In addition to navigating the issues listed above, the other concern I have in going to the .284 is how difficult it might be on the shoulder. Overall I think the rig will be pretty hefty: Kelbly Atlas action, 30" Brux barrel, probably a McMillan F-Class stock. Any commentary on challenges (or lack thereof) in shooting the .284 from a recoil management perspective?

Thx very much!

CG

 

[Keith Glasscock]

Hi Carl,

Let's start at the beginning. Straight 284 refers to a 284 that has not had the case taper or shoulder angle altered. There are 2 flavors of reamer for the straight 284. One is for Winchester brass. The other is for Lapua or Norma brass. For F-class, I'd suggest the Lapua/Norma chamber. The difference being the dimensions of the chamber just ahead of the extractor groove being .001 larger.

Neck diameters vary from reamer to reamer. Most of us turn necks, so you'll see anything from .313-.317 necks on most reamers. Scott Harris is running a no-turn reamer. IIRC, it is a .320 neck.

More important than the neck, the freebore needs to be long enough to support the bullet you intend to shoot. Regardless of the success seen by some with shorter freebores, I'd caution you to get a freebore in of .220 or greater for the 180 or 184 hybrid. Donuts form. You can either be away from them with the bullet, or endlessly working on them.

For brass, there is necking up Lapua or you can buy straight 284 Norma brass. Necking up is a one-pass operation. No drama required.

Recoil is a different story. The 284 isn't without recoil. A correctly set up rifle will minimize the bumpiness, but I spent the first three years of my 284 adventure with a bruise on my shoulder. The key is understanding physics. I'm not a hard-holder by any means, but I do touch the recoil pad with my shoulder.

I'm launching the Berger 180 hybrid at 2810 fps. I would be reluctant to change anything about my load or rifle setup now that I have it dialed.

Hope this helps

 

[Rope2horns]

1.What is the nature of the term "Straight .284"? Is that used to mean "regular" or "standard" or "unadulterated" .284 Win? "The original .284" if you will?.......Straight 284 as it sometimes reffered is just that...some improved versions are 284 Shehane and the 284 Walker.

2.I've read of the (lack of) availability of .284 brass - and how people take Lapua 6.5-284 and neck it up to .284. Can that neck up be done in one step - using a .284 mandrel on the .264 out-of-the-box Lapua brass?...yes...if you clean the necks up on either a 7mm expander mandrel will be used.

3.My understanding is a reamer with a slightly-larger-than-spec neck needs to be used in order to accommodate the necked-up Lapua brass. (I saw one post that even referred to them as a .284 Win reamer and a .284 Lapua reamer.) I'll obviously have a conversation with the gunsmith about this, but for gunsmiths that typically do work for this class of rig (this guy does a ton of F-Class building), is it typical for them to have this slightly larger .284 reamer? Or is that another wrinkle I'll need to navigate?...You will want to use the Lapua reamer if you plan on using Lapua or Norma brass.

On a more general note, I'm not a fan of recoil. LOL In addition to navigating the issues listed above, the other concern I have in going to the .284 is how difficult it might be on the shoulder. Overall I think the rig will be pretty hefty: Kelbly Atlas action, 30" Brux barrel, probably a McMillan F-Class stock. Any commentary on challenges (or lack thereof) in shooting the .284 from a recoil management perspective?

Try to get out and soot someones 284 Fopen rig and see if the recoil is to much.....if it is, you can have a RAD installed on your future McMillan stock.

 

[Rope2horns]

What Keith said I'm a slow typer lol.

 

[Nellej12]

Go for the 284 and don't look back. I made the switch last summer and wish I had earlier. Go with Lapua Brass and neck up. It's a real easy process. I don't think the recoil is to bad, put a little shoulder into it will keep the rifle from slamming into you. Getting the weight at 20lbs plus will help too

 

[jr600yd]

The 284 has some recoil just the way it is. I’d get a limb saver recoil pad installed. The recoil isn’t bad but at a match you may go thru 70 or more rounds a day.

 

[jnm300ultra]

Carl, I’m in the same boat as you. I have decided to build a 284. I will be using Norma 284 brass because I don’t want to worry about donuts, or neck sizing up to a 7mm. I thinking about using a 1-9 or 1-8.5 for only the Berger 180 or 184 Hybrid. I still need to get dies to seat a few rounds and see what my neck thickness will be. I want to have 4 thousands clearance. I was told a 320 will work. My freebore from reading should be 225 but I don’t know about the new 184 if it will work. I have a thread about the same questions on the 284. Rope2Horns gave me the same advice. Good luck with your build.
Jason

 

[ben_g]

Build your 284 up to weight and and recoil will be no issue.
Mine is at about 9.8kg, shooting 180’s at 2820fps it is quite docile to shoot IMO.
My stock just has a foam recoil pad, nothing fancy.

Shooting prone I can shoot it all day long with no ill effects.

I don’t often shoot from a bench, but when I do I find the 284 requires more concentration than my Dasher but I certainly wouldn’t describe it as unpleasant.

 

[CarlGeorge]

Thanks for the great info and perspectives. I've decided to go with the .284.

The way I looked at it: There are multiple ways to address the recoil issue (and it probably won't even BE an issue) but there are really NO ways to deal with the fact the lighter 6.5 bullets will get blown around when conditions are not ideal.

Thanks again for all the help!

 

[Preacher]

Thanks for the great info and perspectives. I've decided to go with the .284.

The way I looked at it: There are multiple ways to address the recoil issue (and it probably won't even BE an issue) but there are really NO ways to deal with the fact the lighter 6.5 bullets will get blown around when conditions are not ideal.

Thanks again for all the help!

You will never regret that decision, trust me on that..
Did I mention I love my 284 XP-100....

 

[KenOath]

Thanks for the great info and perspectives. I've decided to go with the .284.

The way I looked at it: There are multiple ways to address the recoil issue (and it probably won't even BE an issue) but there are really NO ways to deal with the fact the lighter 6.5 bullets will get blown around when conditions are not ideal.

Thanks again for all the help!

The 284 is a great round, you won’t be disappointed and you’ll tame the recoil it’s reasonably milid IME ..

 

[FeMan]

A word of caution on brass. I ordered 300 pieces of Norma brass when it came out and found out it was a LOT thicker than the WW and Lapua, which in my experience are very close to the same. In order to get the required neck clearance, I needed to shave something like 4-thousandths off the diameter (2-thousandths cut). So for me, I ended up creating donuts instead of curing them. The brass seemed fine but I sold it and am sticking to WW and Lapua as they work with my reamers.

Unless Norma has thinned their brass out, my experience tells me you will need a larger neck diameter on your reamer to get the 4 to 5 thousandths most people want compared to what you would need for WW or Lapua brass. (0.320 or so vs 0.316 ish).