.284 Win VS .284 Shehane

[CyaN1de]

I have a 7mm 1:9 Krieger 17A on order and I am looking at the topic mentioned chamberings for mid-long range F-Class.

Barrel will be finished at 30", bullets will be 180grn Berger and I have RL17, H4350 and H4831SC to play with.

The only option for dies for the Shehane is from Bill himself (custom dies from Redding and Wilson). The dies are fairly pricey plus the fact that I will have to order an arbor press so to reload for the Shehane it's going to cost me in the neighborhood of $500 CDN for Dies and Press.

Is the small % of extra capacity worth the extra cost of the Shehane? Is the difference in accuracy/velocity that drastic?

Thanks for any input in advance.

Richard

 

[TonyR]

Richard.
The Shehane versus straight 284 is more a question of velocity and wind drift than accuracy in my experience. My rifles shoot essentially identical 300 yard vertical at 2700, 2800, and 2900 fps. In fact, the low velocity fireforming rounds give better vertical than any full power loads I have come up with. At distances up to 600 yards, I don't think there is any advantage to shooting the Shehane vs 284 Win, or the 6mmBR for that matter, because you can get to 2800 fps with either case in any barrel I have tested and the wind drift is essentially the same at either velocity at 600 yards. But the extra velocity does reduce wind drift at 1000 yards and I have a couple of "slow" barrels that won't get to 2900+ with H4831SC without pressure signs even in the Shehane case. The 180 Berger will get to 1000 yards at 1600 fps with an MV of 2800 fps and I have had very satisfactory results shooting my "slowest" barrel at that velocity in matches. But I also believe that getting up to 2900+ might be worth a point or two to me in tough conditions at 1000 yards on the F-Class target, given my limited wind doping ability. The competition is tough enough in those matches that I want that advantage but there are plenty of people with better wind doping skills winning with the straight 284.

 

[taylor]

Hi Richard
i have been shooting the 284 shehane for a year now ,and its awsome ,but is it any better than a straight 284 proberly not ,you can push the 284 to nearly same velocity and get the same results ,but the shehane will do it with less pressure saving the brass ,my rifle hammers at 2925-2950 in a 32 in barrel ,my freind is shooting a straight 284 with the same load as i use 56.5grns H4831 sc and he gets 2900 + fps and he is hammering those vs he got the highest amout of v count in the european champs ,i made my own dies and built my own rifle but if i paid for a gunsmith to do it i would of never of went the route of the shehane it would of cost to much .
both of these calibers are awsome it depends on if you need that 25-50 fps for the price of the dies .
all the best
Grant

 

[TonyR]

Grant.
I agree. I wouldn't do it for 25-50fps either. I guess I have been assuming that the 284 Win and 284 Shehane cases would have accuracy nodes at the same velocities in the same barrel. I hadn't considered or tested the possibility that the 284 Win would tune at different velocities than the 284 Shehane, everything else being the same. I have extensively tested three 31 inch barrels with different powders and they all need different amounts of powder to achieve the same velocity but the accuracy nodes all occured within a 20fps band around 2800 or 2900 fps so I have been assuming that the difference would be 100fps not 25-50. Some of the 284 Win shooters over here are also using 32 inch barrels and they also report the best vertical accuracy in the "25-50" range but they seem to be somewhere in the 2850 vicinity, not 2900+. It also appears that your barrels are faster than any I have tried. It takes between 56.9 and 57.7gr of powder to get up to the 2900 node in my 31 inch barrels and the slowest of them shows pressure signs that high up with H4831SC. I wonder if jumping versus jamming bullets has anything to do with these differences. I believe that you are required to seat your bullets off the lands. Anyway, I lot to wonder about. Congratulations on your great showing at the European Championships.

 

[falconpilot]

Tony,

Ran my 284 Shehane thur an Oler 33 crono today...I've finally got real world velocities that I know are right...

57grs 4831SC
Three fired Laupa Case
CC! BR2
180 Berger VLD seated using 1/2-1thousand neck tension..
Soft seated out at 25 thous, allowing the bullet to seat itself..
30.5 inch Broughton 5C with 500 rounds down it - 1:9 twist
Bat M Action

20 shot string
Low - 2896
High - 2913
Ave - 2903
ES-17
SD-6

I allowed the barrel to cool every five shots shooting this string...

I was expecting 2950fps or more with this load, but surprised to find these figures! Good news is that it will shoot under 1" -5shot groups at 300 yards all day...

I think that alot of people are a little confussed or maybe mislead(not on purpose of course!), but what they read sometimes on the internet...Those guys that are getting 2900fps out of a straight 284 using 56+ grs of 4831 have to be running crazy high pressures, and destroying brass!! I think a realistic number for the 284 Shehane is right around 2900fps. The pressures aren't too high, and should give good brass life...So, to me...the selling point of the Shehane is the fact that I can run lower pressure, have good brass life, not worry about a load going"too hot" on a hot day, and still push the VLD 180's at 2900 fps, which seems to be a magic number....

Jim

 

[CyaN1de]

Thanks for the responses.

Nothing beats my 6BR out to 600m (700ish yds) but beyond that, if it's windy....forget it, that 105grn pill just starts dancing around willy nilly.

I was hoping to get up into the 2900's to take advantage of the higher velocity/less wind drift but if it's only a matter of 25-50fps difference I am not sure if the cost is worth the gain.

Now I have to wonder if I should have went for an even longer barrel (31-32" finished) to get velocities up a bit. Maybe the 30" won't cut it.

2850 with the 180 Bergers should hold better wind than my 105's running at 2950.

I built a .260 Rem (6.5-08 HABU to be exact) to take advantage of the higher BC bullets but with the 140's @ 2840 (Accuracy Node) and the 105's at 2950, the ballistic difference was less than .3moa at 900m (1000yds) on paper anyway.

I still have to think this one through but I appreciate the advice given as there is not a lot out there on this cartridge other than whats posted on the 6mmBR website.

Richard

 

[TonyR]

Jim.
I'm glad to see you back with the Shehane although you seem to do pretty well with your Dasher. I reached the same conclusions you have with respect to the Shehane, especially the part about pressures. I think that the big vulnerability of the 284 family is the rebated case head and the tendency for primer pockets to loosen up very quickly if the pressure gets too high. The heaviest loads in my ladder tests sure loosen them up quickly enough although I have continued to shoot them. I really don't have much of a feel for brass life. I think the most firings I have on a single case might be 5 or 6, but I doubt that it is going to be as good as the 6mmBR cases. BTW, my extreme spreads and SDs are similar to yours.

 

[falconpilot]

Tony,

My buddy built a 284 Shehane using my reamer, same action, etc.....He and I are using real close to the same loads. Chris has fired one piece of brass 11 times while breaking in his barrel....After the first firing, the pocket loosened quite a bit, the second firing even more, and from there on, it feels the same after every shot...very easy to seat the primer with little pressure, but they don't seem to be getting any worse after the 1st or 2nd firing....I've found similar results..I've got some cases fired 5 times now, and they feel the same as a once fired....loose, but not overly loose..

Jim

 

[taylor]

hey tony
i also jam my bergers in the lands about 15 thou ,my barrel is actualy finished at 32.5 inches i tryed 57.5 grns of h4831sc and it gave me 3020 fps with no pressure but verry poor verticle ,maby my barrel is fast but i do regular crono test on my loads with a ced millenium and i get 2920 fps av to 2940 av fps from summer to winter maby my crono is wrong by a little amount ,but i only care about accuracy and at 56.5 it hammers my come up for 1000yds are spot on for 2950fps
hope this helps
all the best
Grant

 

[TonyR]

Hi Grant.
Based on some Quickload analysis, the extra barrel length is probably aacounting for most of the difference in velocities we are seeing in our respective rifles with H4831SC. At the moment, I am mainly curious about how the velocity accuracy nodes move with changing barrel length or any other variable. I feel that I have plenty of unused potential velocity at my current loads and I have been wondering if I would gain anything by, for example, shortening or lengthening the barrel a bit to see if the nodes would move off the even hundreds more to the "50s". Might just give it a try with my next barrel change. As you say, accuracy on the paper is all that matters and I have had the same experience with bad vertical at around 3000 fps. I have been able to get up there with N560 but the vertical kept openning up and I didn't see any point in going higher due to pressure and barrel wear. I might try a little RL-17 sometime to see if that works better. Like you, I am very confident in my velocities because my comeups from 300 yard zero have been spot on at 600 and 1000 even if the 300 yard zero is set at one range and the match shot elsewhere. I think that the work Bryan Litz has done getting accurate BCs for the Berger bullets has been very helpful.
Thanks for the input.

 

[msb]

Tony,
Are you using a 1-8.5 twist on your barrel? I was reading where most of the shooters shooting the 7-WSM were using that twist with 180gr. Berger VLD's.


Mark

 

[taylor]

Tony
A good freind also shoots the 284 shehane with the same reamer and same barrell (bartleins ) he uses the same load as i do, even seating depth is the same ,and his barrel is only 30 finished he is also getting the same come ups as me he reports 2930-2940 fps ,so the node is exsactly the same for that reamer and barrel make and length .
richard as for twists all the uk 7wsm crew are using 1-9 twists and bergers 180
as so am i for the shehane and its crazy accurate at 1k ;D
regards
Grant

 

[TonyR]

Grant
Thanks again for the input. There are obviously some factors determining the velocity nodes that I haven't figured out. It's more curiosity than anything because both of my guns already make me look better than I am in matches. The ability of that 180 VLD to shoot through stuff at 1000 yards, regardless of the case and powder charge, has to be experienced. I have a Bartlein 1:9.75 to 1:9 Gain twist on order for next season and I will be interested in how it behaves

Mark
I have shot both 1:8.5 and 1:9 twists and I feel that the 1:9 is fine to 1000 yards at the velocities and temperatures I have been shooting in. I haven't shoot a 1:9 at 1000 in real cold conditions but, with the bullet arriving at 1000 yards with 1600 fps retained velocity, even with MV of 2800, I don't expect stability to be a problem in any conditions I'm likely to be shooting in. I would be very careful using a long, tight, 1:8.5 twist barrel at velocities around 2900 fps and above with thin jacket 180 VLDs because I have blown up some thin jacket bullets in my 1:8.5 twist barrel. A very experienced friend has told me that my 1:8.5 barrel, a 31 inch 276/284, has the "perfect storm" of conditions to blow up bullets: long barrel, tight bore, fast twist, slow powder, high velocity and long, fast strings typical of F-Class on a hot summer day! Ever since, I have only shot it in matches at 2800 fps with thick jacket bullets and have had no problems. This not a complaint about the barrel. It hammers them consistently at 1000 yards at 2800fps MV. My 1:9 barrels continue to shoot above 2900fps with no problems, however I am going to shoot only thick jacket bullets in competition just to be safe. Despite my difficulties with them in that barrel, other shooters I know are using the thin jacket bullets in their 284 Wins with no problems although I think they are all using 1:9 twist barrels. and I don't believe they are shooting at or above 2900 fps.