The 280 Ackley improved explored as the ideal non-toxic round
The 280 Ackley is one of the only Ackley Improved cartridges to make it into commercial manufacture. As such brass is available pre ‘Ackley’ed’ and in the US and elsewhere, except the UK annoyingly, factory ammunition is readily available from a variety of suppliers.
As we transition into a market where game dealers and end consumers will not accept lead in their game meat, as deer stalkers we’ve had to change to non-toxic bullets.
Making the non toxic calibre of choice
I looked for the ideal cartridge to use in this new non-lead world.
What I wanted from a cartridge was 7 mm or above, to give a good cross sectional area, the ability to send 150g + bullet at significant velocity and also to be able to be built on a standard bolt-face long action rifle to make it an affordable and readily accessible platform for rebarreling. The standard bolt face also enjoys the ability to fill the magazine with a full amount of ammunition whereas, if I’ve used a Magnum bolt face, the magazine capacity would be lowered.
So having looked I decided on 7 mm, which I’ve always enjoyed for deer shooting, next was the cartridge. I looked at the Shehane and the 7mm Rem mag. The shehane has a bigger diameter body, which I wanted to avoid, for the magazine capacity and I try to avoid belted cartridges (we have build both of the above so have chamber reamers available so could easily have done any of them). However, the 280 Ackley just fitted all the criteria so much better so settled on it.
The 280 Ackley fits the criteria in terms of action. I also have history with Ackley cartridges, shooting a 260 Ackley Improved very effectively through my 1996 accuracy international. So know how much velocity can be gained over the parent case and how consistent they can be.
So in terms of what to build the rifle on, our choice was pretty made up for us as; we had an old stainless Sako 75 in 30-06 as a trade-in and was in very poor condition. Perfect.
Obviously, we were going to use a HS Precision barrel as they are in our experience without peer. But to decided on the profile, we wanted a bit of weight in the barrel to keep any potential muzzle flip under control, we also wanted to build to use it on the range and put multiple rounds through it and explore the long range capabilities, but at the same time we didn’t want it to heavy so we could not take it up the ‘hill’ for the hinds this year. So we went with a standard H&S precision varmint profile and heavily fluted it with six flutes and we chose a 1-in 7.5 twist. The total length of the barrel is 22 and a half in which as you’ll see with the load data later proved to be a great choice as we managed to get all the velocity we need. The barrel was threaded 18×1 for one of our Accurate Enforcer Suppressors. The rifle will only be shot with the suppressor on.
The Sako 75 action, although excellent from the factory, did need a little bit of care to bring it back to great condition. We also deleted the only silly feature of the Action, the locking system at the back of the bolt. The Sako 75 is not only well made and accurate but benefits from a recoil lug connected to the action as apposed to the later models where the recoil lug is in the stock rather like a T3 .
All the metal work was stripped and Ceracoated in satin black. Ideally we would have used an HS Precision stock but HS Precision do not make a stock inlet for the Sako 75. And neither do many other manufactures and if they do, they are made to order with a long lead time. We did, however, manage to source a McMillan stock for this rifle.
The finished rifle was sent down to the London proof House to get its proof marks. A requirement in the UK and the rest of Europe.
Loading the 280 Ackley improved
The cartridge requires a slower powder and the powders that I have at hand are Vihtavuori N560 and Hodgden Superformance
SP with Barnes
Powder, grains. Velocity, fps
57 – 3020 fps
58 – 3050 fps – where we settled.
59 – 3090 fps – too hot and marks on brass from extractor, ejector.
The rifle is extremely accurate, easy to load for. Shoots ELDx as well as Barnes and Hornady non Lead bullets perfectly. Velocity is easy to achieve and long range ballistics are excellent due the excellent BC’s of the 7mm. From the ballistic soap experiments we have carried out, all the above fil luse with confidence to use on deer from the smallest UK deer (Muntjac) through to large lowland reds. Where this will really come in to its own its hill hinds in January in Scotland where weather is not normally your friend with high winds and difficult shots. If there is a calibre that will help ease these shots we believe that this is it.
We have subsequently used this rifle to test multiple non-toxic non lead bullets on ballistic soap.