7mm 08 ackley

[VAspeedgoat]

So I have about decided on some serious work to be done on my 700 mountain rifle and the thought of changing from 7mm 08 to the improved version came up. I have been told it will come close to 3000 fps with 140 grain bullets. Does anyone have any knowledge or opinions about this? Sounds good on paper but what will it do in the real world?

 

[Deleted member 16014]

If you google "big stick 7mm-08 ackley" there is a few evenings worth of interesting reading. There is a lot of good information if you can sort it out.

 

[noharleyyet]

If you google "big stick 7mm-08 ackley" there is a few evenings worth of interesting reading. There is a lot of good information if you can sort it out.

That dude does know his weaponry

 

[MKotur325]

Not sure if this helps or not... but if you are thinking about rebarreling it anyhow... The .284 Win shares action length and bolt face with the 7-08. Should be able to get 3000-3100 out of a 140 with the .284 win. Maybe more a touch more...

 

[jryoung]

If I was going to make the effort I'd consider reaming to .284 winchester with a long throat. Might be about a push in terms of cost, brass, dies, but you'd save a bit of time w/out fireforming. That said, the AI may get you longer life in the 7-08. Can't go wrong with either.

 

[Ben Lamb]

If I was going to make the effort I'd consider reaming to .284 winchester with a long throat. Might be about a push in terms of cost, brass, dies, but you'd save a bit of time w/out fireforming. That said, the AI may get you longer life in the 7-08. Can't go wrong with either.

Will the 284 win w/ a long throat still feed well in a short action? Your COL will be the determining factor, no?

 

[MKotur325]

Will the 284 win w/ a long throat still feed well in a short action? Your COL will be the determining factor, no?

SAAMI spec on the .284win is a short throat so that it can function in the 2.8" magazines of the Winchester 88 and 100. Should be able to push that throat out a bit and still work with the 2.860" box on the Remington...

 

[Deleted member 16014]

Pick a bullet or two that does what you want it to (BC, terminal performance, etc.), a velocity you want to achieve, and pick a chambering to get you there. Maybe it's 7-08, maybe it's not...
My favorite thing about my AI'ed .260 is that I'm on my 6th firing and haven't had to trim brass. I settled on pedestrian velocities because those loads shot well with very low variation, and I've shot it on steel at distance (600+) a decent amount. I wouldn't complain about another 50 or 100 fps, and I could get it, but there's so much more to the puzzle. I only know enough to know how little I know, so I try to keep things simple.

 

[VAspeedgoat]

The conversation started with me inquiring about the .284. He liked the idea and we even talked 6.5 284. In the end he seemed most familiar with the ackley as it is apparently his favorite. Dont want that to make my decision which is why I asked you guys, so thanks for the great info. He felt it would take a little work to get the .284 to workin the receiver and the ackley wouldn't need as much.

As far as balistics, if I can do it, I would like a balistuc equal to a .270 or .280. If what he said is true, the ackley should do this. He did say he wanted to go to a 22 or 23 inch barrel.

Man! This has gone a long way from just getting a new stock!

 

[danr55]

There are two specific risks with converting the chamber of a rifle to an improved cartridge. The first is the reloading aspect. After your fireformed your cartridges, you should take a cerocast of the chamber and one or two fire formed cases and send them to someone to make the dies to fit your particular chamber. While they are all usually close, no tow are exactly the same. The second is developing a load. This can be a lond and involved process. Frequently folsk just run out of patience. Since there is a SAAMI cartridge that is as good as or betret then the 7mm-08 AI you would probably be smarter just to convert to 284 Winchester.

 

[HighDesertSage]

Then why wouldn't you just get a 270 or 280....They have been pushing 140 gr bullets at ~3000 FPS for decades.

 

[tarheel]

The .284 case is .135 longer than the 7-08 but the SAAMI OCL for both cartridges is the same (2.800). If you go with the Ackley it will straighten your walls a bit and might require some tweaking on the feed rails. The dimensions of your magazine might come into play also. I built a .280 on a Mauser action and have been jumping through hoops to get the mag and feed ramps stretched as far as possible to accommodate the longer case and the two bullets I want to handle the heavier game will have to be fired single shot or move the bullet well back off the lands in order to get it to fit into the mag.You're only looking at a case (.284) which is right at 3 mm longer where mine is 7 mm longer so it might not present too much of a problem.
For me the greatest advantage of the AI is the prolonged case life, but not worth the expense in my mind.

 

[VAspeedgoat]

I was hoping that no one would ask me about the .270 or .280. Honestly the short answer is I already have a couple of .270`s and I have always liked short actions better than long. In my opinion a short action best embodies the idea of a mountain rifle. None of these are particuarly great answers but thats the mindset.

I was happy with the 7mm 08, but thought I could push the envelope and maybe get same balistics with less recoil, longer case life, and a lighter gun.

 

[HighDesertSage]

I was hoping that no one would ask me about the .270 or .280. Honestly the short answer is I already have a couple of .270`s and I have always liked short actions better than long. In my opinion a short action best embodies the idea of a mountain rifle. None of these are particuarly great answers but thats the mindset.

I was happy with the 7mm 08, but thought I could push the envelope and maybe get same balistics with less recoil, longer case life, and a lighter gun.

Right on, I was just curious. I wanted to make sure you knew that you can get a mountain rifle in those calibers...lol.

 

[BuzzH]

So I have about decided on some serious work to be done on my 700 mountain rifle and the thought of changing from 7mm 08 to the improved version came up. I have been told it will come close to 3000 fps with 140 grain bullets. Does anyone have any knowledge or opinions about this? Sounds good on paper but what will it do in the real world?

How close are you getting to 3000 with the 7-08 and 140's now? You should have no problem getting to 2900-2950 with the standard 7-08 and 140's.

 

[VAspeedgoat]

I have never put it on a chronograph, but the manual has it around 2850. I have pushed it higher with powders like superormance but the patterns sre not nearly as good. So that lead me to beleive the increase in case capacity would give me the velocity I want without pushing too hard. Maybe I am completely mistsken, I don't pretend to know that much on working up loads. I just experiment till something works and stop. Put all of this on the the forum because it is the best way I have to double check what I am being told by the gunsmith. Consequently all of you guys are really helping me out. I find it is easier to admit your ignorance and ask questions than to bluff your way through, so thanks to all for your help.

 

[1_pointer]

If you go with the 284 or it's variants, you might have to think about getting a Wyatt's extented mag box and altering your action to use it. Alot depends on what bullets your wanting to use. As Snowy said, pick the bullets then the case to push them. If your using 140gr bullets of mostly standard shapes, you could probably get by with the 284 and for sure can with the 7-08 or AI. But if you want to try some of the sleeker bullets you may run out of space with the 284 but probably won't with the others. Also, I wouldn't fret over 100fps, which you probably won't get with an Ackley coversion, as it won't matter in the end. All things equal, you will increase velocity about 25% of the percentage increase in case volume. So if case volume goes up 4% you gain 1% in velocity.

I can probably still throw a baseball faster than 100fps...

 

[blue devil]

I have a Ruger #1 .257 Ackley Improved and love it! But that's taking a smaller caliber and making it quite a bit faster and it gains quite a bit fps. But I decided against it with my .280, because that is already fast and powerful enough to kill anything I want to already.

Gaining 100-150 fps on the 7mm-08 isn't worth it in my opinion for the same grain of bullet.

 

[double_a85]

Is there a reason you want to stay with 140 grain rounds? I have a friend that shoots 120 grain barnes out of his 7mm-08... still kills elk and gets ya above that 3000 fps.

 

[VAspeedgoat]

Good question double, the more I get into this the more I have been considering a lighter controlled expansion bullet in a 120 grain bullet like a barnes tsx. I haven't decided for sure about anything just yet but the more I really think through it the more I am favoring the .284. Because then if I make rhe change I am gaining some nostalgia of an underated cartridge as well as a little more velocity.

Disclaimer: one of my favorite authors once wrote that an elk doesnt care how fast the bullet left the muzzle if it goes through its heart, and I fully buy into that notion so please don't jusdge me as if I am strictly doing this for performance. It is mostly to have a semi custom rifle and to have something a little different than the norm.

I also once heard a guy in Montana say you can tell an eastern hunter because all they worry about is caliber and camo pattern...........I guess I'm not doing much to change his opinion!

I'm not trying to reinvent the wheel, just trying to have a little fun since I have a couple of years of Christmas money stashed. Thanks for everyone's input, I should be able to get away from the farm today and get to the shop and start the process, keep the suggestions coming in please!!!!!!