284 Win Build, help me spec out please!

[KYpatriot]

[size:11pt]Howdy everyone...

Well I finally decided to pull the trigger on a custom build. In fact my cousin that I do most of my long range shooting with and I are looking to build two identical rifles. We were hoping the hide would come through as usual and help us not to make any mistakes on the build.

Our goals:
Shoot accurately out to 1000, maybe occasionally slightly longer.
Reduce the serious wind drift we are getting from 308s/.30 cal 175SMKs
Keep barrel life at least 2000.
Mostly prone target shooting, sometimes the occasional long hunting shot but I have other rifles for hunting

So the 284Win seems to fit the bill...good barrel life and great ballistics out to at least 1000, the 7wsm seemed unecessarily hard on barrels for the range we need. Definetely will go with the long action for this round.

So how does a Surgeon 1086r with a 27 or 28 in Bartlein #9 heavy varmint in a mcmillan a3-5 sound? Or maybe a Krieger?

Some questions:

1. What DBM/mags for the surgeon would you recommend? Will need to sest long, possibly out to 3.2ish right? Will the normal surgeon dbm work with the 284? i have heard others are using the 300wm aics...

2. Looking at using 162 AMAX, 168 or 180 VLD. I am leaning towards 162Amax because of the price and the versatility. Assuming I can get the 162AMax to 2950 in a 27in tube JBM says the amax will be flatter than the 180VLD at 2850 with only a couple inches more drift at 1000 in a 10mph cross. Anyone else experience that? Hopefully the Amaxs will shoot in this build I dont see a need for the 180s at 1000 or less.

3. I plan on buying Lapua brass and sizing up. Previously I have never necked brass up or down....I read that the Sinclair expander mandrels are what I need...another thread some folks had issues with the lapua brass forming donuts...not sure what that is about or how to avoid it. Is the lapua brass really worth that effort over sorted winchester brass? or is it just an availibility issue from winchester?

4. Ok...the heart of the build: the barrel and chambering. Planning on a 9 twist and 5r rifling. I need some advice on the neck and freebore. What freebore/throat do I need to be optimized for the 162 amax? Some say a tight neck isn't necessary for the 284 or that it may even be detrimental...what is the consensus on that? Since I am sure many have set up the 284 to run the 162 Amax with either lapua or win brass shouldn't the chamber neck size I need be pretty well established already?

5. With a 27in barrel and the 162, what kind of velocity should I get with 4831sc? RL17? Hoping to get 2950 out of it without having to change the load for summer.

What am I missing? How would you do it different and why?

Thanks yall.

 

[Dirty D]

Re: 284 Win Build, help me spec out please!

This article won't answer all of your questions but may get you pointed in the right direction.

http://www.6mmbr.com/gunweek088.html

Charles set the record with a 32" barrel but he was also trying to max out velocity for the 180 Bergers, there are good accuracy nodes for the 162 AMAX that won't require that long of a tube.

 

[Insite Arms]

Re: 284 Win Build, help me spec out please!

My Build is:
284 Win
1086 action
Mcm A5
Krieger 5r heavy Palma & a spare MTU @ 28"
APA LB Brakes
Jewell Trigger

I think the freebore is .190 ( but .218 sticks in my mind so I would need to check) neck dia is .318
-I use Lapua brass sized up with a Sinclair expander from their neck turning kit - then size down with 0.313 bushing

The muzzle brake isn't really needed and can come off for a comp when they are not allowed.

180 gr VLD Bergers
CCI match Lg rifle primers
52gr RL 17
2900fps .....deviation of about 8-9fps

Robert Gradous built this rifle for me and it is awesome. Shoots every load I've tried into egg-shaped holes - way better than I can shoot. Best shooting rifle I own.

IMHO the 284 is the best balanced, most under-rated cartridge going.

 

[KYpatriot]

Re: 284 Win Build, help me spec out please!

Thanks Followthrough I would be really interested in the chamber specs/ what reamer he used. Is .313 the neck dimension on a loaded round then? 2900 on the 180s sounds great!

Really looking fwd to getting this started. Thanks for all the 284 fans who have put so much good info out there on the round. 300calsniper, bobinnc, ky338, and many others in other threads put out the data convincing me to go with the 284. Once I get the specs done I will need to find a good smith to put these twin rifles together.

 

[Boltfluter]

Re: 284 Win Build, help me spec out please!

When you choose a smith to do the work make sure the <span style="font-weight: bold">reamer</span> is for a .284 w/Lapua brass and not Winchester. Ask me how I know this. Damn.

. Hope this helps. Regards, Paul.

 

[KT35]

Re: 284 Win Build, help me spec out please!

Great thread,
I'm building a 284 for F-class.
Savage Target action
SSS stock
bartlien 32inch barrel

KT

 

[KevinU]

Re: 284 Win Build, help me spec out please!

my 284
Bighorn LA in a AICS stock
AI 300wm mags, have two 5rd mags. Had to slightly bend the lips on one of them, can snugly fit 6rds
Bartlein Hvy Palma 1-9 27"
Reamer .185 FB, .317 neck

Shooting 175smk's with 4831SC.

Started out using Lapua brass, after two or three firing developed severe donuts. Switched to Winchester brass, no difference in accuracy, slight velocity increase. Lightly turning necks for a loaded .313.

If I were to chamber another 284 and wanted to use Lapua brass, would go with a .313 neck and turn the necks to a loaded .309.

 

[steve123]

Re: 284 Win Build, help me spec out please!

Hmm...tight neck being detrimental, why I wonder? Nearly every chambering I own has a tight neck. Never had one problem ever. My rifles aren't benchrest rifles either.

The best balance I've found concerning neck expansion is .003". This enables you to clean the neck and only have .004" expansion or if you choose not to turn .003" gives enough clearance. My main tactical rifle has .0025" expansion now. I shot the rifle before for years with .002" expansion with zero problems.

This is what I'd do. Try to borrow a set of 284 dies or buy some used ones if possible. Go in with your friend on a large quantity of Lapua 6.5-284 brass all the same lot number. Buy a sampling of the bullets you want to use. Seat to the depths you prefer leaving room in the mag for throat erosion and land chasing. There will be compromises here in freebore because of the different ogive shapes and baring surface lengths. Send them off to PTG to have the reamer optimized for minimum case expansion in the web area and shoulder suitable for a tactical rifle. When you get the rifles built send some cases off that have been fired and neck sized 3 times to a custom die maker. Although you would have spent quite a bit of money doing all this you will discover that the brass will last seemingly forever and the rifle if built correctly will shoot crazy good. One of the other things I like about having my own reamer and custom dies is when I get a new barrel put on I can use the same cases I've already been shooting for years. They fit the new chamber exactly.

I assume you and your friend are ordering a custom reamer? Call Dave at PTG and tell him exactly what you want. He'll help you figure it all out.

 

[braso]

Re: 284 Win Build, help me spec out please!

162 Amax is .313 with Win. brass. reamer neck is .317.
Skip the Lapua and go with the Win brass. although it is a seasonal run and some times hard to find, it works great and you ahould see that 2950 fps pretty easy.

 

[turbo54]

Re: 284 Win Build, help me spec out please!

I have a short action, my freebore is .088", but that doesn't apply to you...

My neck is .317"

Ive measured loaded Lapua brass @ .312", for .0025" clearance/side

I've measured Win brass @ .3135", for .00175" clearance/side

Im not a fan if neck turning and refuse to do it. If I were to spec out another reamer, I'd go .319 or .320". In my (limited) experience, a tight neck isn't good for much other than making loading ammo more difficult. At 317, my neck is pretty tight as is! .0025" ain't much.

 

[300sniper]

Re: 284 Win Build, help me spec out please!

my chamber neck diameter is .317" and have never had a problem with winchester brass in it. i shoot in all conditions from snow, rain, sun, well bellow freezing to well over 100*. i had 11 firings on my last brass without ever annealing the necks. it was still shooting incredibly good and i see no reason the brass wouldn't keep going. there was no thinning in the web area, no split necks and the primers pockets still stayed tight. annealing would be a good idea after every few firings though. i have several barrels in use with this reamer and i haven't heard a single complaint about the neck diameter. i have no reason to stray from the .317" neck.

 

[KYpatriot]

Re: 284 Win Build, help me spec out please!

Right on, thanks, sounds like .317 neck is good to go. I am planning on the 162 amax so what throat do i need for that? What overall length should i plan for? Will the 180s have a problem with a rifle set up for 162s or am I overthinking this?

 

[braso]

Re: 284 Win Build, help me spec out please!

You're over thinking it. Call PT&G and talk to Dave Kiff, tell him what you want to do with it, what bullet, what brass, and he can set you up

 

[turbo54]

Re: 284 Win Build, help me spec out please!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 300sniper</div><div class="ubbcode-body">my chamber neck diameter is .317" and have never had a problem with winchester brass in it. i shoot in all conditions from snow, rain, sun, well bellow freezing to well over 100*. i had 11 firings on my last brass without ever annealing the necks. it was still shooting incredibly good and i see no reason the brass wouldn't keep going. there was no thinning in the web area, no split necks and the primers pockets still stayed tight. annealing would be a good idea after every few firings though. i have several barrels in use with this reamer and i haven't heard a single complaint about the neck diameter. i have no reason to stray from the .317" neck. </div></div>

I can appreciate this, but I think 317 is too tight:

If you miss/forget casemouth chamfering, the round won't chamber.
A bit of dirt/debris, round won't chamber
317 neck provides "perfect" clearance for Lapua brass, but too tight to be "perfect" for win brass.
Increasing neck clearance by several thou will have a minor, minor effect on caseneck life, but will provide more tolerance for dirt/debris/burrs.
A little more than "perfect" clearance isn't going to affect accuracy.

I guess it comes down to the rifles purpose. Benchresters are all about tight necks. Not totally sure why, as I've experienced fantastic bughole accuracy with SAAMI necks that provide tons of clearance. Anyway, if you won't be under any time pressure when using the rifle, and/or you'll have good control of environmental factors, no issue having a tight(ish) neck. If it's a field rifle - a tight neck isn't ideal. I don't know what the neck dimension is on an AIAW 308, but I'd bet a lot that it provides more than .002"/side.

 

[300sniper]

Re: 284 Win Build, help me spec out please!

how many times have you had a malfunction due to the .317" neck and how many rounds were fired through it? i know several people shooting winchester brass with the .317" neck and i haven't ever heard of a problem. it wouldn't surprise me if there have been well over 10k rounds fired on the same line as me using those chambers and if a malfunction happened due to the neck size, i sure haven't heard about it. i have 3300 rounds with mine in all conditions and never had a round not chamber due to the neck size. we're shooting in the dirt/mud/rocks, not benchrest. if you can't chamber a round due to dirt/debris in a .317" neck, i'd say there's a pretty good chance a .319" neck isn't going to chamber either. do you stress out that there may be a bit of dirt/debris in the chamber lead that is only half a thousandth over the bullet diameter?

if you don't feel you can prep cases reliably and may forget to chamfer the case mouth, a caliber that requires hand loading may not be right for you.

 

[KYpatriot]

Re: 284 Win Build, help me spec out please!

Thanks everyone, a lot of good info here.

I just got off the phone with Dave Kiff, who was very patient with my questions. He told me he sets up 284s with a freebore of .160 for the 162Amax, or .188 for the 180VLD. If you want to shoot both need to go with the .188

I told him I wanted a no-turn neck for the lapua brass and he said that he would go with .317

I am a little concerned about that neck, as I want this thing to be reliable, if it doesnt hurt to open it up a couple thousandths seems that might be the practical way to go. God knows the chamber on my 308 isnt custom and it is easily sub-moa so I am not convinced it is critical either.

For those of you shooting the 162 Amax, have you had any problems getting them to shoot with .188 freebore or more like the 180VLD needs? I would like to be able to chase the lands a little, I know it isnt a 6.5/284 but still I expect to get some erosion.

So a Surgeon 1086r, Bartlein or Krieger 5r at 28in, somewhere between a.317 to.319 neck, with .188 freebore. Anybody see any problems with that for 162amaxs and 180vld's?

If not let's talk barrel contours. I was thinking the heavy varmit would work fine...but don't really know beyond aesthetics if there are real functional differences among the heavy barrel contours out there.

And we havent even got to triggers yet, I'm thinking the Jewell HVR sounds good.

Details, details. But to me still more fun than talking about golf...thanks again for all the advice, keep it coming please!

 

[KYpatriot]

Re: 284 Win Build, help me spec out please!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 300sniper</div><div class="ubbcode-body">how many times have you had a malfunction due to the .317" neck and how many rounds were fired through it? i know several people shooting winchester brass with the .317" neck and i haven't ever heard of a problem. it wouldn't surprise me if there have been well over 10k rounds fired on the same line as me using those chambers and if a malfunction happened due to the neck size, i sure haven't heard about it. i have 3300 rounds with mine in all conditions and never had a round not chamber due to the neck size. we're shooting in the dirt/mud/rocks, not benchrest. if you can't chamber a round due to dirt/debris in a .317" neck, i'd say there's a pretty good chance a .319" neck isn't going to chamber either. do you stress out that there may be a bit of dirt/debris in the chamber lead that is only half a thousandth over the bullet diameter?

if you don't feel you can prep cases reliably and may forget to chamfer the case mouth, a caliber that requires hand loading may not be right for you.

</div></div>

300cal thanks alot for the work you went to on the 284build thread, it is great. I am meticulous about reloading so that isnt a concern, and you're right that a thousandth or two might not help with dirt anyway. Either way, I think the rifle will shoot ok I am just trying to optimize things best i can.

One question for you if I get the reamer from PTG set up for lapua brass, will it still chamber winchester as well?

 

[turbo54]

Re: 284 Win Build, help me spec out please!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 300sniper</div><div class="ubbcode-body">how many times have you had a malfunction due to the .317" neck and how many rounds were fired through it? i know several people shooting winchester brass with the .317" neck and i haven't ever heard of a problem. it wouldn't surprise me if there have been well over 10k rounds fired on the same line as me using those chambers and if a malfunction happened due to the neck size, i sure haven't heard about it. i have 3300 rounds with mine in all conditions and never had a round not chamber due to the neck size. we're shooting in the dirt/mud/rocks, not benchrest. if you can't chamber a round due to dirt/debris in a .317" neck, i'd say there's a pretty good chance a .319" neck isn't going to chamber either. do you stress out that there may be a bit of dirt/debris in the chamber lead that is only half a thousandth over the bullet diameter?

if you don't feel you can prep cases reliably and may forget to chamfer the case mouth, a caliber that requires hand loading may not be right for you.

</div></div>

Throughout the firing of over 5k handloaded rounds through my loosey-goosey Savage, I've had two rounds not chamber - both times because of a dirty chamber.

Throughout 24 rounds through my 317 neck 284, I had 6 that wouldn't chamber because I hadn't done a sweet enough job deburring the casemouth.

My fault? Yeah, pretty much...but somehow, magically, my pisspoor reloading practices allow me to shoot bugholes at 200-300 yards with my loose 308.

More thorough and meticulous loading will make the 317 neck work fine, but I just don't feel it is any "added value"... Just more of a headache. I load to shoot, and like it to be as hassle free as possible, so a 320 neck (or bigger) would help.

 

[turbo54]

Re: 284 Win Build, help me spec out please!

KY: The 317 neck clears win brass (without neck turning), though it's a bit tighter than Lapua. I gave measurements in an earlier post.

 

[KYpatriot]

Re: 284 Win Build, help me spec out please!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">KY: The 317 neck clears win brass (without neck turning), though it's a bit tighter than Lapua. I gave measurements in an earlier post.</div></div>

Thanks turbo. Thats the dimension Dave K at PTG gave me too on the neck.

 

[KYpatriot]

Re: 284 Win Build, help me spec out please!

Ok I have been getting a lot of conflicting info on brass. Hoping to clear that up now.

Some have been having great results with winchester...I dont think anyone can argue with 300snipers results with his build using win brass.

More shooters seem to use lapua though and neck up. A few have had problems with donuts forming from the neck up process, not sure if everyone gets that or not.

I would try both but apparently the chamber dimensions on a custom reamer are different enough that lapua, being slightly larger, wont chamber well in a chamber for winchester brass.

So is it really worth it to deal with the lapua brass donut issue? What brass prep over and above the lapua is the winchester going to require to get the same results?

 

[Jon Lester]

Re: 284 Win Build, help me spec out please!

I run win brass through whatever chamber reamer Moon at GAP uses. Barrel is 27"bartlinen and a LA rem in an ACIS chassis feeds rounds through a mixture of 300wm and 338 lapua mags. 168 bergers go over 3k and the rifle has finished in top 5 at every match it went to but 1 last year, including ASC and Mammoth.
284 flat works.

 

[KYpatriot]

Re: 284 Win Build, help me spec out please!

Right on Jon. Do you weight sort the Winchester brass, or do you have a whole brass prep routine?
Was the freebore set for the Berger 168 specifically, do you know what it is? I was hoping to use the 162Amax since it is a little less money and still has a great BC. Any thoughts on that?
Great shooting BTW, congrats.

 

[Jon Lester]

Re: 284 Win Build, help me spec out please!

Out of the bag and through the die,total prep. Whatever Moon set for freebore is where it is at. Shoots the 162 a max well and when the 168 bergers are gone this time, hornadys will be the bullet of choice as they are 1/2 the price.

 

[KT35]

Re: 284 Win Build, help me spec out please!

Any updates?