.284 Shehane and .284 velocities 26" barrel with 180's???

Mar 22, 2014
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Central Texas
#1
Thinking of building a hunting rifle in .284 Shehane or straight .284. Could I get some feedback on velocities out of a 26" barrel with 180's. Most everything I find on velocities of the Shehane are the Fclass guys running 30-32" barrels. Thanks
 

kabarNC

Learning..
Feb 11, 2017
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State line of the Carolinas
#2
20170415_103141.jpg

This is a Bartlein 26" barrel in straight 284 with Berger 180 hybrids. I'm in the low mode here with H4831SC. You could push it more than this, I chose the low node for a little more barrel life and because it shot so well.
 
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lou400a

Sergeant
Feb 27, 2008
373
43
28
SE Florida
#3
This is a Bartlein 26" barrel in straight 284 with Berger 180 hybrids. I'm in the low mode here with H4831SC. You could push it more than this, I chose the low node for a little more barrel life and because it shot so well.
How fast are the lighter bullets like 162 eldx? Thinking about punching out 7mm-08 to 284 win on stock Tikka ultralight 22" barrel
 
Feb 12, 2009
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SW Virginia
#5
28" shehane fire forming load with 180's 54 grains h4831sc 2800fps. 54.3g with formed brass to maintain that velocity.
56.3 is where I maxed out at 2990 if I recall correctly. My data is in storage. Building a house so it will be a while before I can verify or produce more info. Shehane if a great cartridge but for a hunting round I'd go straight 284
 
Dec 22, 2010
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New Jersey, USA
#12
I love the 284 and it will be my next build. I've always wondered why it doesn't get more attention in this community.
Mostly because you need to run it in a long action to get the full benefit of the round using the heavier bullets. Most of the shooters here prefer short action unless they plan to run the big magnums.
 
Jul 29, 2014
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#13
doesn't offer much over the 7SAW velocity wise. seems like a waste of a long action to me unless you have a tikka or something that it's going on
 
Dec 22, 2010
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New Jersey, USA
#15
I had ES Tactical spin me up a 28" Proof steel barrel for my DTA in straight 284. I had to modify a short action mag to get it to work, but it was worth it. I can run the longest bullets with room to spare and the accuracy is incredible. I've had sub 1/4 moa groups using Sierra 168s at 3000 fps, single digit SDs and no pressure signs. And before anyone rips into about making BS accuracy claims; no, the rifle does not a average sub 1/4 moa. But, it does average sub 1/2 moa with ease.

I hear SAC is working on a new "midsize" mag that should aliviate the need to modify a factory mag. You will probably start seeing more DTAs chambered in 284 once that is available.
 
Feb 11, 2017
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#17
doesn't offer much over the 7SAW velocity wise. seems like a waste of a long action to me unless you have a tikka or something that it's going on
I think you're right with this.

However, if you could run a 284 and 180s with the new defiance medium action and their 3.2" OAL magazine...
 
Aug 4, 2008
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Columbia Falls, MT USA
#21
I wenr 284 shehane. It is supremely accurate with fireforming and fireformed loads. The fireforming loades have larger ES so I used those for hunting 500 yards and in. The neck on my chamber was looser so I never had to deal with turning or reaming my lapua brass. Shot Winchester brass fine as well. I have since moved on, not out of neccesity, but because I like to try different calibers.

Mine was a Surgeon long action, aics mags and fed like butter.
 
Apr 6, 2017
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Georgia
#23
Have a 26” and a 28” straight 284, the 26 loads where 4831sc 180 eldm was maxed around 2850 but accuracy was better around 2800. The 28 I tested 4831 and RL17, same 180 eldm was around 2900 again accuracy better around 2800, rl17 maxed up near 2950+ accuracy better down around 2850-2875. All these out of long action 3.225” (28”) on the one and ~3.24” on the other (26”).
 

DJL2

Hurricane 6
Oct 16, 2013
86
37
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Center of the Military Universe
#25
Thank you. I'm asking to figure out if the .284 might work as an AR-10-ish chambering, hence the 2.815 length limit.

I'm figuring a rifle+ length gas system. Any constructive thoughts on the concept would be welcome.

Thanks again.

Greg
Might be less work to run a 7mm CM - sure, you won't get the same velocity, you should also be able to run it from the magazines with no problem...basically, the same reason the 6.5 CM exists versus the .260 rem. Now, if you're going NEMO style... .284 should have plenty of room, but I near completely unfamiliar with the magnum ARs.
 
Feb 27, 2008
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SE Florida
#26
Have a 26” and a 28” straight 284, the 26 loads where 4831sc 180 eldm was maxed around 2850 but accuracy was better around 2800. The 28 I tested 4831 and RL17, same 180 eldm was around 2900 again accuracy better around 2800, rl17 maxed up near 2950+ accuracy better down around 2850-2875. All these out of long action 3.225” (28”) on the one and ~3.24” on the other (26”).
Are you using 30-06 or 300 wm mags and how do they feed?
 

Greg Langelius *

Resident Elder Fart
Aug 10, 2001
5,754
1,009
113
Arizona, good place for me...
#29
No idea; hence, I ask. But the .30AR seems to run OK with one (...or does it?).

BTW, I'm kinda hating Rem for changing the bolt face diameter to something hokey. Personally, I think they stepped on it right there; a small capacity 30 with a .473 bolt face diameter would have had me by the short and curlies.

Hint, hint, maybe somebody should wildcat something along such lines...; maybe a tad more capacity than the 30AR? I tried the 30BR and it was OK; but the barrel I was using had a sub-optimal bore. This is a different application from the larger 7mm we're discussing, but stiil an unfulfilled hunch of mine.

The 7CM piques my interest, but since I already use 7-08 brass for my .260, I guess going with 7-08 has possibilities.

But it doesn't have the case capacity of the .284.

I wouldn't even be considering the .284 except that I really liked the .280 Rem when I had a pair on loan. I was convinced I'd never get that into an AR, and am definitely not going NEMO (just too much gun for me).

But if the .284 could fit and run in an AR-10 setup, my interest piques yet again.

Greg
 
Last edited:
Jul 29, 2014
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#30
No idea; hence, I ask. But the .30AR seems to run OK with one (...or does it?).

BTW, I'm kinda hating Rem for changing the bolt face diameter to something hokey. Personally, I think they stepped on it right there; a small capacity 30 with a .473 bolt face diameter would have had me by the short and curlies.

The 7CM piques my interest, but since I already use 7-08 brass for my .260, I guess going with 7-08 has possibilities.

But it doesn't have the case capacity of the .284.

I wouldn't even be considering the .284 except that I really liked the .280 Rem when I had a pair on loan. I was convinced I'd never get that into an AR, and am definitely not going NEMO (just too much gun for me).

But if the .284 could fit and run in an AR-10 setup, my interest piques yet again.

Greg
have you looked at the 7SAW with the .045 freebore reamer? i know the 162 ELDM sits at 2.850 with it
 
Aug 10, 2001
5,754
1,009
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Arizona, good place for me...
#33
This is getting more and more complex, I'd really like to get back to the original questions, regarding the .284 Win.

Shoulder angle considerations, special chamberings, and small primer cases are not very interesting to me at this stage.

FWIW, if my option is for the 7CM, I'd just as soon go with the 7-08.

But again, I was looking for the .284's additional case capacity, and that's not drawing a lot of support from the forum.

I think I'm going to retire to my fortress of solitude and reconfigure my priorities.

Greg
 

ck79au

New Hide Member
Jan 6, 2019
5
1
1
#34
Thinking of building a hunting rifle in .284 Shehane or straight .284. Could I get some feedback on velocities out of a 26" barrel with 180's. Most everything I find on velocities of the Shehane are the Fclass guys running 30-32" barrels. Thanks
Quick Load program works very well for all calibers bullet weights and powder combinations
 

ElvisUSMC

Im a dude playing a dude disguised as another dude
Feb 15, 2017
13
7
3
#35
Here is a good article that really gets into the weeds of a .284win short action build.

http://www.6mmbr.com/gunweek095.html

Greg, I don’t think a large frame AR build in .284 is going to work out all that well. That cartridge does best when you can get a 160-180gr bullet seated out of the case a bit. That requires a modified Rem700 (feed well area milled out) or a custom action like a Defiance, ARC, etc with a larger feed well. Also a ACIS style mag without the binder plate will allow a COAL of 2.9xx”, depending on brand. An AR mag, even the SR/LR mags (Armalite pattern not DPMS) won’t get you that COAL.
Another critical consideration for an AR platform is gas. The .284 has a much larger capacity vs a 7mm-08/7CM/7SAW, you will have that extra gas to deal with, for proper cycling of your action. Bolt timing, ejection, and feeding is going to be messed up. The bolt carrier will most likely be slamming into the back of your action as well, which is obviously bad. You would most likely need a custom gas port, gas block, rifle length gas tube, and buffer assembly, as well as a lot of tuning to manage that. There would probably be feeding issues with a non-modified AR mag as well with the larger body of the .284.
Keep in mind the .284 is essentially the primagenitor of the Short mag, a large frame AR isn’t designed for those forces. You only have so much metal between the chamber wall and the outside of the barrel in any AR profile barrel and with a high pressure cartridge I would be concerned. 5.56mm AR’s still have chamber ruptures or catastrophic explosions from time to time. Yes, “thumper” cartridges like the .450 Bushmaster, .500 Beowulf have thin chamber walls but they aren’t high pressure cartridges. Personally I wouldn’t be comfortable with that.

Hope this helps
 
Aug 10, 2001
5,754
1,009
113
Arizona, good place for me...
#36
ElvisUSMC; Thanks plenty. This is the sort of info I was looking for. I was thinking on the outside chance, and I can see now that it was a pipe dream.

My goal was to cobble up a 7mm Semi for extended distances, and I was exploring the claims that the .284 was designed as a short action sorta-magnum. Apparently that claim makes less sense with the LR-suited bullets. My fault for falling in love with the 280 Rem, then looking to stuff that kind of performance into an AR-10-ish package. Not in the cards.

More importantly, the idea of a quick followup at extended distances falls flat, since the extended TOF allows the bolt rifle the opportunity to fill that niche well enough.

Your common sense dissection has helped me immensely in understanding that some dreams may end in nightmares.

Greg
 
Feb 11, 2017
307
183
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State line of the Carolinas
#38
Just curious but what's the purpose for this rifle build? I'm intrigued by the idea.
Thats a great question.. short answer is, for leisure steel shooting to 1200yds and to find out if I could get it to run in a Tikka long action configuration. I actually started out in my PRS journey with it, but like eveyone else I opted for a lighter recoiling cartridge.

I still love this cartridge. When the barrel is shot out I will rebarrel to 284 again, but lighter contour for hunting.
 
#39
Thats a great question.. short answer is, for leisure steel shooting to 1200yds and to find out if I could get it to run in a Tikka long action configuration. I actually started out in my PRS journey with it, but like eveyone else I opted for a lighter recoiling cartridge.

I still love this cartridge. When the barrel is shot out I will rebarrel to 284 again, but lighter contour for hunting.
It would probably be quite an elk cartridge!
 
Likes: kabarNC

fdkay

Gunny Sergeant
Nov 27, 2009
3,820
476
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Ingleside, Tx
#40
ElvisUSMC; Thanks plenty. This is the sort of info I was looking for. I was thinking on the outside chance, and I can see now that it was a pipe dream.

My goal was to cobble up a 7mm Semi for extended distances, and I was exploring the claims that the .284 was designed as a short action sorta-magnum. Apparently that claim makes less sense with the LR-suited bullets. My fault for falling in love with the 280 Rem, then looking to stuff that kind of performance into an AR-10-ish package. Not in the cards.

More importantly, the idea of a quick followup at extended distances falls flat, since the extended TOF allows the bolt rifle the opportunity to fill that niche well enough.

Your common sense dissection has helped me immensely in understanding that some dreams may end in nightmares.

Greg
Well, you could always rebarrel a Garand with an adjustable gas block to .280.
 
Aug 30, 2008
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tn
#41
This is getting more and more complex, I'd really like to get back to the original questions, regarding the .284 Win.

Shoulder angle considerations, special chamberings, and small primer cases are not very interesting to me at this stage.

FWIW, if my option is for the 7CM, I'd just as soon go with the 7-08.

But again, I was looking for the .284's additional case capacity, and that's not drawing a lot of support from the forum.

I think I'm going to retire to my fortress of solitude and reconfigure my priorities.

Greg

http://forum.snipershide.com/threads/whos-running-7-08.132850/