MY PAIR OF 284(SHEHANE)'s

[DaveMc]

These are the rifles I used in the Nationals. The wood stock is a savage target action timed and trued by Fred Moreo of Sharp Shooters Supplies and one of his offset dogtracker stocks with a Brux 7mm 1 in 9 inch 30 inch, 1.25 straight barrel. I used this one from 300-800 yards but would have happily kept going with it except I had the BAT below working at higher speed with pointed hybrids. The scope is a converted sightron 10-50 with Peter Smith custom reticle (Big thanks to Peter Smith for all his help).

The other is a BAT trilug dual port action (yes I can here you groaning from here Bruce), on a converted McMillan F class stock. I added some carbon fibre and foam layers and an offset and it tracks beautifully. I have to thank Phill Mastin and truflite for a pair of great 32 inch 1 in 9 twist barrels that, at this early stage, seem as accurate as each other (and the one I had last year so 3/3 for Truflite). Scope is a March 5-50 which I am extremely happy with. Also a big thanks to Mark Fairbairn (wild dog) and Peter Smith (once again) who diagnosed my bedding problem over a few wines on the last night of Mackay queens. Since then this outfit has been humming.

All chambered in 284 SHEHANE

As discussed with Marty we just have to work out how to bottle what we have now and open it up again next year. It seems whilst it is hard to get them humming, it is even harder to keep them there.

[jcinsa]

Thanks for that Dave,

nice story, interesting

John

[bruce moulds]

dave,
you have posed the eternal question. who has the answer to that one has the way to bask in the sun.
my current theory is twofold.
first is the relationship of the bullet to the lands. what works best needs to be established and maintained.
second is the width of the node. a very narrow node can disappear for a number of reasons.
possibly a wider node which is slightly less accurate would offer more honesty from rifle/ammo combos.
sometime you question equipment when conditions refuse to allow such precise aiming as you are used to.
good luck,
bruce.

[DannyS]

Hi Dave,

I notice on the sightron that you have white and black markings on the turrets. Did you make up your own?

[OuttaAmmo]

Thanks for the pics and info.
Now, if you don't mind, can you tell me what Peter Smith does/offers?
In short, I've heard he pulls optics apart and improves them, but can you elaborate?
Are you not using the cheek piece on your green stock?

[DaveMc]

Yes I made the knobs after much discussion with Peter Smith and several trial versions. A close up picture attached.


Peter is a brilliant man, very humble and giving. He isn't set up to do anything commercially and does this sort of thing for his own interest and to help people out. In my opinion he is also one of the finest shots in the country. I don't wish to advertise for Peter as that is probably not what he would like but just think the least he deserves is some thanks.

On the cheekpiece I do shoot with it in I just remove it and store with bolt. The cheekpiece has about a kg of tungsten powder embedded in resin. The plan was to remove and put on a lighter barrel for 17lb weight limit in benchrest but haven't got that far yet so it stays in for F class (total weight still on the light side around 9kg)

[DannyS]

Thanks Dave, nice photo & job on the turrets, so when are you going to market them?

Cheers
Danny

[AlanF]

Dave,

I have a machined aluminium and steel stock on the drawing board which has an offset fore-end. I notice the green stock has a higher profile fore-end than the other. Do you notice any difference between the two stocks as far as torque recoil goes?

Alan

[DaveMc]

Danny, Thanks but they are only printed on photo paper, stuck on with glue and covered in cellotape - hardly marketable but easy enough to do at home. I bought a spare turret cover from herron security to make the cut down cover. We tried to do same for Nightforce but not enough height on every turn so was a bit messy.

Alan good question. I designed the stock originally to try and utilise vertical sides to counteract torque as well as the 3 inch bottom. I also wanted to stick within the FS rules as may put a 308 barrel in occasionally so kept it under 25mm of vertical. It works well in the seb neo bags with high parallel vertical sides (tracked beautifully with no torque roll) but not as well in the sinclair bags that really only contact bottom and not much of the sides. After thinking about it some more I think really only the lower right side and left side of bottom are most important. The left hand vertical side won't be doing much except holding against the right unless there was a high vertical on left above barrel height. The depth of stock also allowed several carbon fibre and foam sandwich layers for strength and rigidity.
The low profile SSS dog tracker is very good in a standard bag and if doing it again I would probably go that way.

[DannyS]

Dave, almost anything is marketable these days, sometimes it just takes a bit of refining, anyway thanks for the info, will have a go at making some for mine. I had tried Kenton Industries but they don't do turrets for the 10-50, apparently can;t get the blank turrets.

Cheers
Danny

[Batman]

Hi Dave
Nice pair of rifles you have there
I have a couple of questions for you as Im building a new rifle myself using a bat action and thinking going with straight 284 and 10 x 60 March
so my questions are.
Is there much between the straight 284 and Shehane
is the Shehane more temperamental than the 284
any reason you choose the 5 x 50 March over the 10 x 60
and what rectile are you using in your March
thanks
regards Stuart

[DaveMc]

Gday Stuart,
I don't think you can go wrong with either case. The 284 Sh isn't temperamental at all. I actually have 4 barrels shooting really well with "wide" nodes now. Some barrels are just a little better than others. Mainly on velocity spread so shows up in the longer ranges.
I originally tried the Shehane to try and get to the higher node but quickly realised it wasn't going to happen in the first Truflite barrel and settled back to very similar loads to what everyone tends to run in their straight 284. I do have one barrel running at the higher node very well (also a truflite) but it is a bit of a lucky dip as to whether each barrel can get you there (1/4 for me). Too close to the pressure limit and the 284 case suffers early from head expansion issues. Some might be happy pushing it but not me.
So it really comes down to this. At the same load the 284 Shehane is doing it at very slightly less pressure so nicer for extraction and case head issues (e.g. loose primer pocket etc.). BUT disadvantage is having to fireform and also make custom dies etc. Not a big issue once you are set up and going (I fireform at club level in the "second" grade barrels) but worth considering. I do personally believe it is a slightly better cartridge but at some cost so very balanced and not much in it. Most guys make a couple hundred straight 284 cases last the lifetime of the barrel anyway. Of course there is a chance you can get to the 2950+ velocity in a SHehane case with the right barrel - much less likely in a straight 284.
On March Scopes I was very fortunate to be able to run a scope comparison (shoot out) with Peter Smith, Shane Green and Marty Lobert on 4 March Scopes, several Nightforces and 2 Sightrons. The 5-50 March that Stuart sent up for us to compare came out very slightly ahead of everything else that was there so I snapped it up (closely followed by NF 12-42BR and 8-80 March with each having its +ves and -ves). It has beautiful optics and tracked perfectly, no zero shift right through zoom and focus range and looks very robust. Peter smith was literally champing at the bit to pull it apart and get a look but I won't let him (yet). We didn't get to test a 10-60 though (2*8-80, 1*2.5-25 and a 5-50).
Reticle I like is the MTR3 but mainly because it is as close to Peter Smiths reticle I can get in a commercial scope. I love setting it at 40 power and using minute holdoffs plus measuring fall of shot in minutes but each to his own.

[Brad Y]

Dave its interesting what you are saying about being in lower nodes with the shehane. Good to hear some real life experience actually. The way the yanks make the shehane sound is like it guarantees getting to the 2950-3000fps bracket. By the sounds of it maybe they are still using RL17 to get the velocity required.

In your rifles (I dont know exact weights on them) but what is recoil like say compared to the 308 in a FS gun?

[DaveMc]

Brad - I know a couple of the guys that push the Shehane to these velocities and they do it OK but the cost is brass. probably 3-6 firings per case before primer pockets get too loose. Remember the 284 shehane is a rebated rim so at same chamber pressure it is putting out about 13% more bolt thrust over a standard 308 case. No problem with good action and most are built to take the magnum bolt face and associated thrust but cost is damage to the case head. Also barrel life must be somewhat reduced as well.
I am pushing one barrel to those velocities and it is doing it a lot easier than the others but it is still a little harder on the cases. I have heard some barrel brands can get the velocities better than others and Broughton seems to spring up in conversation when discussing this.

All my 7mm rifles (yes there is more!) currently weigh in betwen 8 and 9 kg and recoil is a little more than a 308 at 8kg. Especially torque roll. 180 grain through 9 twist compared to 155gr through 13!!! I don't mind it at all and would be a whole lot better at 10kg (probably similar to 308 at 8kg), The old stock was a handfull with torque roll and I had to pull down on it in rest to counter. These two pictured above handle it beautifully.

I haven't put the weight up yet as I intend to build a 7mm Magnum to the full weight limit as well and don't want there to be too much difference in felt recoil in case I jump when hit by it. I notice I have to be careful stepping back up from 6BR or 6.5x47 to 284SH.

[Brad Y]

Interesting to hear mate thanks. Sent a pm your way.