Make it or break it time lads. I have a sako 75 long action and a 24" proof barrel in 7mm. I was dead set on a 284 build but my smith is pretty sure it wont feed and recommended 280ai. Is the barrel long enough? Thoughts appreciated.
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Make it or break it time lads. I have a sako 75 long action and a 24" proof barrel in 7mm. I was dead set on a 284 build but my smith is pretty sure it wont feed and recommended 280ai. Is the barrel long enough? Thoughts appreciated.
Had the same tough call to make! Ended up going 280ai and love it! 22” barrel pushing the 162amax at 2870fps with 1 hole groups. Could get more speed if needed as no sign of pressure but accuracy over velocity wins for me.. https://uploads.tapatalk-cdn.com/202...21c1d8f895.jpg
https://uploads.tapatalk-cdn.com/202...1d197e32e1.jpg
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What a waste of a target! All that space and you're only using one tiny bit.:thumbsup:
Only have one target, remains as new...my groups are so goddam tight so as all the holes completely disappears. :DQuote:
Originally Posted by canuck hunter
Should not be an issue with feeding, you might have to open up the lips on the mag slightly for284 but not a show stopper. I’m not a gun smith but I’d be asking another Smith for a 2nd opinion.
284 vs 280ai very little in it and really depends on what bbl length you want to run. To get best out 280ai you need 24in and some would argue longer. 284 as you know will tolerate shorter bbl. I’ve built 3 284s two at 20in bbl one at 22in. With 160 TMKs or 162 AMAX I get 2830-2850 FPS in 20in and 2930 FPS with 23 in. This with RL17 or Superformance. With 24 in 280ai and 24in bbl I get 2980 FPS. All built pretty light. Recoil on 280ai is sharper and harder than 284s
You'll be happy either way. I'm not sure how one would feed better over the other, but i believe its no biggy to change the feed rails a bit. My 284 doesn't like feeding eldms, but it feeds everything else. That's on a sako 75 long action.
284 feeds perfectly from Tikka mags. Can't imagine a Sako would be worse. I get identical performance to chainsaw - 160's at 2850.
Not sure why your gunsmith thinks the 284 won't feed well....it will.Quote:
Originally Posted by cameronjackwhite
For both the 284 and 280ai a 24" barrel is absolutely fine.
From memory (might pay to check), the 280ai holds about 5 grains more powder than the 284 and can give 100-150fps more velocity. Some consider that worthwhile....I don't due to the hassle of fireforming. Yeah fireforming is simple but I just find it an extra unnecessary step if the 284 is an option.
However saying that...based on the availability of brass alone, I would go with the 280ai as one can use 30/06, 25/06 and 270 cases if need be.
If 284 brass is available and priced right though, then I would stick with your initial idea of a 284 in the long action Sako (long throat reamer) as I just can't be assed with fire-forming.
Never encountered a feed issue with my 284
You can get 280ai brass now I think
As said, if you want a shorter barrel to accommodate a suppressor then 284 be the go. If running bare or braked then 280ai will have a performance edge
If you're a long pointy plastic tipped bullet fan then 284 all the way.
284 brass is available from Peterson via Workshop Innovations.
284 will give you the room to seat long pointy bullets out without running out of mag space too quickly. Though you may still do so if the siren song of the 180s gets a hold on you...
Many pros for the 284 - only con I can think of is you may lose one round of capacity in your mag. I have a friend who rebarreled a 75 from regular 280 to 284. As far as I'm aware it is performing brilliantly. I'll check with him on the feeding and mag capacity questions.
This, will give you way better flexibility for loading while remaining at mag lengthQuote:
Originally Posted by Steelisreal
I’m a big fan of the .284 having had one with a 16 inch barrel and now a 20 inch & love it even more.
I also had a .280 rem for a while and can also attest the recoil is more than a .284
Not meaning to throw a spanner in the works but as you have a long action, a 24 inch Proof barrel... not sure it that’s one of their carbon or steel barrels BUT another calibre I’d seriously consider is a 7mm Blaser!
https://www.nzhuntingandshooting.co....um-info-42743/
so just to clarify a 284 will be ok in a short action ? just pondering something at the moment :DQuote:
Originally Posted by Seventenths
It's a bit shitty for the longies. Sweet for regular cup and core
They are a bit tight man. Won't be able to run any of the long heavies which is where the 284 really shines. Really are better suited to a long action. Fine if you want to mag load a 140gr soft point and single load anything with a good bcQuote:
Originally Posted by dannyb
so partitions would be ok ? if so out how far ish ?Quote:
Originally Posted by Nick-D
To clarify, barrel is 24" and carbon fiber. Dont think it would take to well to shortening! Haha I was going 284 as i have dies and brass already. I also love the caliber. It will be unbraked. I love the go fast pointy projectiles and was looking to shoot in the 170 range. Eldm, tmk etc. I can always sell dies and brass and change but I'm a big fan of 284.
Sounds like you've answered your own question! Go for it ��Quote:
Originally Posted by cameronjackwhite
I had a Winnie with extended box. Think mag fit was right on 3inches. (I think) I shot 150gr sgk and 160gr speer btspQuote:
Originally Posted by dannyb
Yeah they are pretty stubby so should be fine. Will get them moving along if you keep a bit of barrel to work with.Quote:
Originally Posted by dannyb
Greetings All,
I would recommend against forming .280 AI cases from anything other than .280 Rem. The head space dimension for .280 Rem cases is about .050 inches (1.25 mm) longer than the other .30-06 based cases which will be stretched badly in fire forming. While it can be done by necking up to .33 cal and necking down to 7mm again this is not worth the bother. The head space on the .280 was increased to stop people (Americans that don't read labels) chambering the .280 in a loose .270 with predictable results. The same thing was done with the 7 mm WSM for the same reasons. Unfortunately when the .280 was renamed the 7 mm Express the same people chambered it in the 7mm Rem Mag, a startling but not as dangerous. Best to use the right cases to start with.
Regards Grandpamac.
Some good information here - particularly my contribution obviously :thumbsup:
https://www.nzhuntingandshooting.co....chester-57681/
My M70 284 built on short action with mag spacer removed gives you 3.1 mag length.Quote:
Originally Posted by stevodog
Sweet, what pills do you use in it Bobba?
So where does the 7x64 fit in this discussion. Sako and tikka both chamber it, the barrel twist of a factory 7 x 64 will allow you to throw heavies also. The case capacity, velocity of the round is equivalent to the e .284, and brass and dies are available off the shelf from norma, lapua, geco, rws etc
7x64 is ballistic equivalent of the 280.
Yep, despite having a decidedly average BC the 150 or 160 gn partitions launched at something around 2800 fps will perform very well out to 500 yards or so. The front end is pretty frangible so even at longer distances it going to be an emphatic killer, and the back end hangs together to provide plenty of punch through up close or far. Given the crappy bc your wind reading ability needs to be pretty good.Quote:
Originally Posted by dannyb
Have you considered a standard Mauser action ? the 7x57 8x57 (57mm) cases are longer than a 308 and shorter than a 3006 so the mauser is a med length. Or rather than a 284 what about a 7x57 AI which is a perfect case capacity to bore diam. Just get a 7mil and ream it AIQuote:
Originally Posted by dannyb
Still in the development stage and rifles just been put back together after fitting a dpt and new scope but was working up the 150 game kings which looked promising. Heaps of pills to try but will probably just stick around the 150 g weight.Quote:
Originally Posted by stevodog
Chainsaw,
Yes appreciate similar to the .280 but more common in euro rifles than the 284 and 280. Comes with a fast twist 1:9 barrel? And good brass available Long throats etc. off shelf option
I’d go with .284 Win. In fact I did.
Mine’s on a T3, which is ideal as a short action cramps their style. My 162 ELD-Xs seated long still leave about 3mm of spare space in a T3 long mag.
I use Lapua 6.5-284 brass necked up and get 2740 fps with 2213sc. Could get more but it’s accurate at that. That said, I have some RE26 and might stretch its legs at some point.
Whatever you decide both with be great.
Right so anyone built either of these calibers on the sako 75? Alan Carr is in the process of chambering new barrel in 280ai and thinks the 2 bottom locking lugs will catch the shoulder of the 2nd round in the mag on the backward stroke?
Yep - a friend of mine had a standard 280 which he recently had rebarreled to 284. His results so far with the new barrel have been very pleasing. Here's what he told me:Quote:
Originally Posted by cameronjackwhite
Yes mine was standard .280, the Ackley will be fine also, the only slight problem is with the steep shoulder angle the 2 bottom lugs of the 3 lug action tend to catch on the round in the mag when retracting the bolt. This isn't a big problem- you just need to be fairly positive when pulling the bolt back. It also happens with the 35 degree shoulder on the
.284 case. The long .280 case also doesn't leave a lot of room for bullets and typically you will be beyond mag length before you get near the lands with nearly any bullet. The
.284 on the other hand makes for a far superior long range setup and will allow any bullet to get to the lands and still fit in the mag. The Sako mag length is 3.380 inches which with an "06" case and slippery bullet will mean a not fully fulfilled hand loader/ owner.
Not 280ai but 6.506ai built on Sako 75 that started life as 2506. The mag feeding can be tricky due to the steep 40 degree shoulder on the ai, and you need to careful and not too quick on the bolt or you will jam the case. For my long range loads I seat to 10 thou jump and single feed. Bush load partition is seated to mag length.
Wicked so it's not just mine lol. I'm thinking of doing a long range load and single feeding and carrying some standard 280 ammo for anything bush relatedQuote:
Originally Posted by chainsaw
I have a 280ai on a M52 Cooper 3 lug action. It feeds perfectly and there is no catching on the case when drawing the bolt. The sako may have a different lug position though. The benefits of seating bullets longer are overstated generally and If i was in your position I wold throat the chamber so the loaded round would fit the magazine. Im still shooting whats left of my 162 Amax supply. Seated with a .040 jump at 3.380 OAL and running 2950 from a from a 23 inch barrel. The only time you will see any real gain in seating long is if it gives you enough room to drop a burn rate but modern powders like RL 23 largely negate that.
@Puffin your comparison on the other thread is flawed in that by using 2209 you have picked a burn rate the suits the 284 but is faster than ideal for the 280ai putting it at a disadvantage. . I would also add that of all the combinations Iv run through QL over the years the 280ai consistently showed the the largest discrepancies.
The chamber will be throated to saami spec as I had always planned to mag feed. It will also have rl 26 or 23 behind it so should hum along. Will wait and see how if mag feeds and go from thereQuote:
Originally Posted by sneeze
I’ve got a sako 75 280ai and no feeding issues, but running 162 eldm at mag length I’m 10 thou off the lands.
Just today loaded some other 2213sc so will test next week.