Viht 6.5x284 reload data interchangeable with .284 Win?

[JBirchall]

Dear all

I am reloading for my .284 Win and have changed over to Viht powders now exclusively. I notice that Viht only lists 6.5x284 data and not .284 Win data.

I am sure I read somewhere that data for the the .284 Win can be substituted with 6.5x284 data (assuming same weight bullets etc). Before I go down this route I wondered if anyone had real world experience of this and or any opinions from the guru's out there as to if this is a safe route to embark upon (assuming the usual caveats)?

Many thanks

[JabaliHunter]

Sierra has some data for the .284 and Viht powders http://accurateshooter.net/pix/sierra284.pdf

[No i deer]

N165 works great.57grs behind a 162gr amax and 56grs behind 180gr hybrid or 180gr scenar l's. I think N160 will do you up to 160 grainers.not tried it though.i expect N560 would give better performance though.not tried that either.it is high energy powder though.

[mikeroz]

What COAL and barrel length are you shooting those 162 amax from Noideer? I was planning on loading some 162g ELDs with N165,  I ran my data through QL based on 26"  1:8 barrel and 3.100 COAL and it was showing absolutely max pressure at 55.1g of N165. Now I know QL can sometimes be off the mark, however 2 whole grains is a lot. 

Birchall,

if I Remember correctly Nathan Foster in his Ballistics website suggests 280Remington should be a likable comparison.  I wouldn't load againt 6.5x284 as different barrel diameter would give different pressures??.

Where's Laurie when you need him? Cast your pearls of wisdom please Laurie.

[No i deer]

26 inch bartlein.i am actually running 162gr max on 57.5grs of N165. There probaly a little warm.shoot great though.i am gonna drop 0.5grs when the last dozen left are gone.om a warmer day I expect they'e doing 2880fps.if you wanna run them real fast get some RS60.they will touch 3000fps.i only tried a few on it as it' so say a barrel burner

[mikeroz]

Yeah, I have been using RS60 based on MikMacks recommendation, however I too wanted to try less of a barrel burner.

Mine is a Carbon wrapped Hardy barrel 284win with a 0.318 neck. Chrono readings with RS60 were.

COAL 3.114", 51grns, 3 rds in fps;  2862, 2851, 2853

3.151" 51grns, bullet jam; 2843, 2856, 2853

3.100" 51grns, .024 jump; 2817, 2814, 2816

The first shot we took with 51grns measured 2924, I can't remember the COAL but might have been 3.025" before Mik throated it out a bit more whilst I was there.

[mikeroz]

None of those loads were showing any pressure signs.

[Laurie]

There is a difference between 6.5-284/140gn and 284/180gn maximum loads in favour of the latter. (As the two cases have near identical capacities, the larger bore of the latter will reduce pressures with equivalent weight bullets and 180 is the rough equivalent to a 140 in 6.5mm.)

So, this particular gem of wisdom should be safe although it will likely produce modest pressures, but I'd never, ever, ever recommend anyone put a cartridge together on this sort of transposition basis.

For my last (and definitely final) attempt at getting 6.5-284 to work for me I ended up with the 139gn Moly'd Lapua Silver Scenar over 51.8gn N165, in Lapua brass - not a super-hot load, in fact rather mild.

For 284 in F-Class and occasional 'Heavy Gun' benchrest, I use three loads:

1) Winchester brass, Murom KVB-7, 160gn Sierra TMK jumped, 51.7gn N160. (short-range load) ~2,930 fps from 30-inches. (But I prefer my 7mm-08 with the same bullet 100 fps slower also using N160 - this (284) one comes out when the Diggle weather forecast is really bad for 300 yard matches and doesn't see much use.)

2) Lapua (reformed 6.5-284), Murom KVB-7, 175gn Sierra MK jumped, 55.5gn N165, (a standard pressure sort of load neither unduly hot or mild - ~2,830 fps).

3) As 2) above, 180gn Sierra MK in the lands, 57.0gn N165 - no pressure issue in my rifle / chamber but getting 'hot'. I have seen people blow primers with this charge weight of N165 with 180gn Bergers in their rifles / chambers. When I can get a little range time, I intend to do a bit of testing with reduced charges to drop this one to the node below - it shoots very well and is my 1,000 yard load, but is a bit faster (and heavier recoiling) than I want or need at 2,855 fps.

Brass life is so far good with all of the above and annealing every few firings. 284 is widely regarded in the USA as having the major weakness of short brass life due to case-head / primer pockets expanding even in Lapua brass. IMHO, that might be a result of their habit of stuffing them with too fast burning H4350 allied to serious ambient and barrel temperatures with string shooting in US F-Class.

The usual caveats on using others' loads data apply, and charges should be dropped by 10% or so to get starting loads.

[No i deer]

I ran the 162gr amaxs with 52.5grs of RS60 ok.i tried 52grs behind a 180gr hybrid.they did around 2890fps.

Some of the f class shooters run the 180gr hybrids on 52 to 52.5grs of RS60.they get the extra velocites from the 30 odd inch tubes.

[JBirchall]

Thank you Laurie. I was assuming there to be some latitude in favour of the .284 based on the increased bore size as you confirm and so thought it seemed a sensible suggestion to be able to substitute .284 with 6.5x284 data. 

I wonder why Viht don’t list any .284 data? It seems surprising considering the popular use of this cartridge in competition. 

 

[No i deer]

One of my load test 5 shot groups from 100yds.oal would of been around 3.170.