I was able to pick up a 7x57 Ackley built on a HVA 98 Mauser action however, I am having a devil of a time finding any guidance on loads. Sure, I can use mid 7x57 loads and work up but I don't own a chronograph. Does anyone know anything about loads for this round?
The rifle is very nice, 22 inch med barrel, flamed maple stock great condtion. I am confident that with the right bullets and loads, both varmits and deer will suffer. I am also hoping that I can punch some respectable holes in paper to 300 yards or more.

Based on my experience I got my best results with a mildly compressed load of slower powders. LIke MRP. 7828, My favorite was rl19 and 140s. If you don't want to compress then something like H414 or Rl15. Even with a 22" you should be able to approach 3000fps

I never used anything but 160 grain bullets in the one I had built in a Mark X Mauser action with a 24 inch barrel.

This rifle was throated to seat the 160 gr bullet with its base flush with the base of the case neck. Here is one load THAT WAS SAFE IN MY RIFLE. Work up to this from 5% below

WW case, Rem 9 1/2 primer, 55gr of Rl 19, and 160 grain Speer FB bullet. Velocity over my Oehler Chrongraph instrument was 2819 fps.

Hope this helps. Merry Christmas

Thanks guys.

I would think you could start close to the top end of standard 7x57 loads because of the AI. For a great number of years folks didn't have chronies. Read the front section of any good reloading book, and if you don't have any, get some, and it should tell you how to recognize pressure by empirical means.

A guy just sent me some. Mind you, these are near max loads out of a 24" Douglas barrel.
120 grain bullet - W-760 - 57.5 grains - 3365 fps;
140 grain bullet - Reloder 22 - 58.5 grains - 3184 fps;
150 grain bullet - Reloder 22 - 56.0 grains - 3004 fps (could build this up some more);
160 grain bullet - Reloder 22 - 56.0 grains - 2970 fps, and
175 grain bullet - Reloder 22 - 54.0 grains - 2758 fps.

PS: I have almost every reloading book there is have. :-)

quote:

Originally posted by Big Cabin:
A guy just sent me some. Mind you, these are near max loads out of a 24" Douglas barrel.
120 grain bullet - W-760 - 57.5 grains - 3365 fps;
140 grain bullet - Reloder 22 - 58.5 grains - 3184 fps;
150 grain bullet - Reloder 22 - 56.0 grains - 3004 fps (could build this up some more);
160 grain bullet - Reloder 22 - 56.0 grains - 2970 fps, and
175 grain bullet - Reloder 22 - 54.0 grains - 2758 fps.

PS: I have almost every reloading book there is have. :-)

I'd certainly want to work up to those loads. They are beyond loads for my .280 Remington as published in Hornady's manual.

quote:

A guy just sent me some. Mind you, these are near max loads out of a 24" Douglas barrel.
120 grain bullet - W-760 - 57.5 grains - 3365 fps;
140 grain bullet - Reloder 22 - 58.5 grains - 3184 fps;
150 grain bullet - Reloder 22 - 56.0 grains - 3004 fps (could build this up some more);
160 grain bullet - Reloder 22 - 56.0 grains - 2970 fps, and
175 grain bullet - Reloder 22 - 54.0 grains - 2758 fps.

Holy Crap Batman. Running each of the loads through QL using Std capacity and OAL it calculates very close to the listed velocties within 20-30fps. However the loads are 113-115% capacity and pressures are 67,000-70,000 (except for the 150s).

My main 7mm rifle is my 280PDK it is a gibbs style case and 21% larger than the 7x57AI in a 23" barrel my velocities are 3150for the 140s and approaching 3000 for the 160s. Looking at both the Alliant and Nosler sites the velocites posted exceed the velocties for the 7mm Rem Mag.

If you get away with it great there is no way in he!! I would attempt to load a 7x57AI to that level.

quote:

and pressures are 67,000-70,000

This is about what I have come to expect from Ackley Improved listings.

That said.....those loads just might be perfectly serviceable in the right guns. I have a 6.5 X 55 load that might run at that pressure.....and have no problem with it whatever......But one needs to be a tad careful publishing them as we never know what the reader might think of them.

Calling them "near max" loads is somewhat of an understatement.

I am just passing along what I was sent. I am in no way suggesting that anyone use them. As for chamber pressure, an increase powder does not equate equally to an increase in pressure all the time. To state that pressures move from 48,000 to 67,000-70,000 is a bit of a stretch don't you think?

quote:

To state that pressures move from 48,000 to 67,000-70,000 is a bit of a stretch don't you think?

Not at all.....My diagnosis was simply on the fact that the loads for the 7 X 57 AI actually exceeded published loads for the much larger 280 Remington and further that the posted loads were almost equal to loads for the 7mm Rem Mag.

What I call "A stretch" is to refer to these loads as "near max".....don't ya think?

quote:

Originally posted by Big Cabin:
A guy just sent me some. Mind you, these are near max loads out of a 24" Douglas barrel.
120 grain bullet - W-760 - 57.5 grains - 3365 fps;
140 grain bullet - Reloder 22 - 58.5 grains - 3184 fps;
150 grain bullet - Reloder 22 - 56.0 grains - 3004 fps (could build this up some more);
160 grain bullet - Reloder 22 - 56.0 grains - 2970 fps, and
175 grain bullet - Reloder 22 - 54.0 grains - 2758 fps.

PS: I have almost every reloading book there is have. :-)

Given the information presented and the very rough estimate of 3,000 PSI per grain of powder, I'd say to reduce every load by about 2 1/2 grains and you might have some very good working loads.

And, yes, work up to that level.

I agree that the loads as posted are more than warm.

quote:

Originally posted by Big Cabin:
I am just passing along what I was sent. I am in no way suggesting that anyone use them. As for chamber pressure, an increase powder does not equate equally to an increase in pressure all the time. To state that pressures move from 48,000 to 67,000-70,000 is a bit of a stretch don't you think?

There is always fact and fiction.

Speer Wildcat manual had some of Ackley loading data for the 7x57AI using a 24" long 1/10 twist barrel.

47gr to 51gr/IMR-4350 with 160gr bullet max velocity was 2791fps.
I loaded 51gr/IMR-4350 with 160 @ 2824fps in my 24" long 1/9 twist 7x57AI.

Next load in the manual was 49gr to 53gr/IMR-4350 with 145gr Speer max 3005fps and 53gr in my rifle was 2991fps.

I worked all loads up and 52.5gr/IMR-4350 with 150gr bullet @2886fps and 53gr was 2915fps. In the Speer manual I have with those loads they gave a warning on max loads and I just gave the max loads and not my work up one.

I did that rifle about 25yrs ago and if you look at Nolser data for the 7x57 with 150gr bullet max velocity 2831ps and 2686fps is max with 160gr bullet. My 7x57AI gained 84fps with 150gr bullet over 7x57 in Nosler manual and 138fps with 160gr bullet and Nolser rifle used a 22" long barrel.

25yrs ago we didn't have the internet or so called experts with the QL. I'm not sure what I'd get today building a 7x57AI getting better bullets and barrels today .

I am thinking of 110 to 130 gr bullets and am hoping that I can go about 3K fps with the 110's or 100's. I don't really plan to hunt large game with a white tail being the largest quarry that I would attempt. Mostly I want to develope a mid to long range paper punching load with a weekend a month out looking for coyotes at 200+ yards.

I should add that I know that it would have been easier and in the long run cheaper to buy a 223 bolt gun but the romance of the wildcats has always called me and after shooting a 7x57 Improved a few years ago I was hooked.
I currently have a Ruger #1 that was born as a 218 Bee that I had immediately reamed to 218 Mashburn Bee....I just can't leave well enough alone. :-)

in both of my 7ackleys, i went with rl-19
as my powder.
i have tried up to 55 grs 4831 and a couple of other powders too.
but settled down with a rem 9-1/2 primer and 52.5 grs rl-19 under the hornady 139 gr interlock. the rem primer settled this load down nicely.

this gives me bout 2850 in one rifle and i haven't chronoe'd in the other yet.
for coyotes the sierra 100 gr over 4895 has done well with a win primer.
i started at book loads and worked them back out
till i got accuracy.
i don't get worked up about velocity much.
unless i am exceeding the bullets capacity.

Thanks Lamar. That is exactly what I wanted to know. How lighter bullets perform is what I am after.

Ladies and Gentlemen:

It amazes me that someone can stare in the face of blinding empirical evidence, and decry, "No, that's not right!" with only the crutch of hyperbole to support their assertion.

Sincerely,

Chris Bemis

Hello
I’ve been shooting a 7x57AI for twelve years now. It’s on a FN 98 Mauser, 22” barrel, done by Chick Donelly, P.O. Ackley’s protégé . This particular rifle is a dream to shoot but has been a little finicky and a challenge to find accurate loads. ( MOA or better). But I discovered later that H-450 and W-785 is absolutely phenomenal in this rifle, and maybe the round as a characteristic, with 150gr and heavier bullets. I happened to have a few pounds left of those powders, but since they are not being made anymore that information won’t do you any good. However, W-780 is proving to be a close second with heavier bullets and Reloader 17 with 150gr bullets.

This rifle has a rather long throat so I’ve had to play around with C.O.L. quite a bit

One of the first things I became aware of with this round was the difference in internal case capacity among Win Rem Norma and now the new PPU cases from Eastern Europe, which BTW is looking like pretty good brass.
For example, I can get 61.5 grs of W-760 in a fire formed Win case, but only 58.5 grs will fit in a Rem case. This, as you know can make a big difference in maxing out a load. So just be aware of which brand you are working with.

One of the attributes of Ackley rounds is, rarely having to trim brass. I have yet to have to trim any.

Now for loads. The loads you listed, I would not fire in my rifle unless I brought a rubber mallet to open the bolt..Way too hot.

I’ll list a few loads that have worked for me well.

140gr Nos Balistic-Tip;
52.5 grs H-4350 Win brass Win primers 2860 fps

150gr Sierra BT;
51.0 grs Rx 17 Win brass Win primer 2725 fps

150gr Nos Partition;
52.5 grs H-450 Rem brass Win primer 2700 fps (½ MOA at 200 yds)

160gr Nos Accubond;
52.5 W-785 Rem brass Rem 9½ primer 2680 fps

160gr Sierra BT;
53.0 grs H-4831 Win brass Win primer 2675 fps
49.0 grs Rx17 Win brass Win primer 2670 fps
53.0 grs W-780 Win brass Win primer 2550 fps

175gr Speer Mag-Tip (no longer made)
52.0 grs Rx22 Win brass Win prmer 2590 fps
52.) grs H-4831 Win brass Win prmer 2600 fps

Some of these loads may not be “max” loads as such, but they are very accurate.

Fire forming is rather straight forward process. Consult the loading manuals and just load some ‘mid-range’ 7x57 loads and shoot ‘em. Or shoot some factory 7x57 rounds.

Mr. Donelly recommended applying a little gun oil on the rounds to be fire formed, to ensure good forming and no failures. I have done this and never have experienced any failures fire forming brass.

Working up loads with fire formed brass is a matter of starting out close to maximum listed 7x57 loads for the bullet weight you are shooting in the manuals and load strings in increasing 0.5 grain increments of powder. Shoot each string with a cold barrel until you either see a good group and tweek from there, or you start seeing pressure signs, like the bolt starts to get heavy to lift. I never saw any reason to shoot any more than three-round groups, after all this is a hunting rifle.

Now, it is very important to understand that when you start to see pressure signs, you are already WAY past nominal working pressure by about 2 grains of powder.

As you will find out you will get 50-100 fps advantage over a standard 7x57 chamber in a stron bolt action rifle, staying within nominal pressure limits.

So that’s what I got… 3¢ maybe..

Good luck!

there is also an i.c.l. 40* chamber that increases case capacity a bit more over the standard ackley round.
my model 70 push feed has the larger chambering.
it is almost not worth trying to resize in the ackley dies as the effort is extreme.
it will give some right impressive velocities with easy extraction but i have found they are not necessary for hunting.
with 139 gr hornady interbonds i have had velocities in the 3100 fps range with very easy bolt lift and ten + loads on the brass.
these same loads in my ackleys are a bit too much.
but i treat every gun i own as a wildcat and the fast side is not where i generally tread.
but i do wander off the books occasionally.

I was under the impression that the 7x57 has a 40 degree shoulder. All the dies that I can find are for a shoulder of that degree.
I know there are some "improved" versions with less than 40 degrees but I think that P.O. Ackley's preffered angle was 40 for most if not all his wild cats.
I may be wrong and will stand corrected if I am.

My bad again...I meant the 7x57 Ackley.

quote:

there is also an i.c.l. 40* chamber that increases case capacity a bit more over the standard ackley round

I thought the ICL version of the 7x57 was called the "7mm ICL Tortilla" I thought their cases had a 45deg shoulder. CAse capacity would be basically the same as the AI. I believe they also had a 7mm ICL Wapiti based on a blownout and improved 300H&H. (WOW 7STW anyone) There was a whole family designed but the smiths that owned Saturn Gun works in Reno I think.

Just stumbled upon this thread and I will echo Lamar. RL 19 is showing a lot of promise in my newly acquired 7x57 AI. 24" Shilen barrel. I am getting around 2850 with a 150 gr Speer and 52 gr of RL19. I still have a lot of load development to go with this little beauty though. I really like the rifle and cartridge.

quote:

Originally posted by RDub:
.

140gr Nos Balistic-Tip;
52.5 grs H-4350 Win brass Win primers 2860 fps
very accurate.

Fire forming is rather straight forward process. Consult the loading manuals and just load some ‘mid-range’ 7x57 loads and shoot ‘em. Or shoot some factory 7x57 rounds.


Working up loads with fire formed brass is a matter of starting out close to maximum listed 7x57 loads for the bullet weight you are shooting in the manuals and load strings in increasing 0.5 grain increments of powder. Shoot each string with a cold barrel until you either see a good group and tweek from there, or you start seeing pressure signs, like the bolt starts to get heavy to lift. I never saw any reason to shoot any more than three-round groups, after all this is a hunting rifle.

Now, it is very important to understand that when you start to see pressure signs, you are already WAY past nominal working pressure by about 2 grains of powder.

As you will find out you will get 50-100 fps advantage over a standard 7x57 chamber in a stron bolt action rifle, staying within nominal pressure limits.

So that’s what I got… 3¢ maybe..

Good luck!

Both of mine like this load with the exception that I use new R-P brass and Fed 210 primers. I usually experience loose primer pockets before hard bolt lift. The key is the sharp shoulder and minimum body taper. It seems to have less bolt thrust at higher pressures than other cartridge designs.

i believe they called it something like the tortilla.
the version i have has a larger body diameter also.
and the 40* shoulder.
my ackley reamer bounces around in there pretty good.
and like i said the cases are about not worth the effort to resize.
they take far more effort than swaging 44 jacketed rounds with ww centers.
the 2850 is right where i get in my mauser ackley with 52.3 grs rl-19 and a 140.
at 15' from the muzzle.

quote:

Originally posted by Lamar:
i believe they called it something like the tortilla.
the version i have has a larger body diameter also.
and the 40* shoulder.
my ackley reamer bounces around in there pretty good.
and like i said the cases are about not worth the effort to resize.
they take far more effort than swaging 44 jacketed rounds with ww centers.
the 2850 is right where i get in my mauser ackley with 52.3 grs rl-19 and a 140.
at 15' from the muzzle.

The ICL version "Tortilla" has a 45 degree shoulder but I believe the body taper is the same. I've only played around with the Ackley versions, which I believe were all 40 degree shoulders. RCBS is the same but with 35 degree shoulders. Parker was a man way ahead of his time. Over a half century ago they were cutting the rims off the 348's and necking them up and down and Ackley improving them. Not far from today's short mags. There's no middle ground with the Ackleys. People either seem to love them or hate them. The gun companies just keep reinventing the wheel.

quote:

Originally posted by vip:
[QUOTE]Originally posted by RDub:
I usually experience loose primer pockets before hard bolt lift. The key is the sharp shoulder and minimum body taper. It seems to have less bolt thrust at higher pressures than other cartridge designs.

Hi Vip
I have heard that the 40° Ackley design "masks" pressure more than conventional designs. I believe this is true for the reasons you state.

You are correct about primer pockets. If you start loosing primer pockets after one or two firings, better drop down a bit.

OK guys I've had one for 15 seasons and it's my #1 hunting rifle.It's a Remington 700 w/22in DouglasXX barrel at 22in throated to 3.00 w/the 140 grain Ballistic Tip.That gives me some wiggle room on the 150's and 160's.Most of you guys should have just stuck w/a 7x57 because that's what your loads are showing and some not even tops.If you build an Ackley...any Ackley it should be to get the most out of your cartridge space.They were made to run hot but not in the red zone. Ackley himself, after much testing said that in his guns that between 5% and 7% above the standard calibers is what his Improved versions are relatively safe.When you look at the case and the reloading manuals, it makes a good deal of sense.
For instance in the Nosler #6 manual it lists the 7x57 w/140gr bullet w/52.0grs of RL19 gets 2890fps.A 5% increase in that load is 3037fps.A 7% increase would be 3094fps.
With the 150 gr bulletit shows 51.0gr of RL19 at 2831fps.And 5% increase equals 2972fps and a 7% increase yields 3020fps.
The 160gr w/Viht 160 shows 2690fps w/a 5% increase showing 2825fps and a 7% increase yielding 2878fps.
All of these loads should be safe in every strong rifle even w/the tightest chamberes.
My loads are all built around RL19 because it has less pressur per volume when loaded.Hodgdon's #5 or 6 manual bears this out for those that would like to look up the pressures showed w/different powders.
My load is 56.0gr of Rl19 in WW cases sparked by a Fed210M primer.Yes it's a 280 load but it just turned out that way.It's accurate a the reads 3050fps.So I am at barely 5% and no pressure signs.Kicks a little more but is deadly out to 400yds.
When all the dust settles and you take a closer look you'll see a 250AI is really a 257 Robts w/bullets up to 100grs.The 257AI is a 25-06 straight up.The 7x57AI is just a 280 and the 30-06AI is just a 300H&H.
All of the loads listed by Rolltop w/the exception of the 150gr load are way over pressure and am surprised whoever's data it is still have a face and all their digits.Mr.Ackley knew people would try to overload his cartridges and that is why he gave us the 5-7% as a safety margin. Just my 2cents, powdr

Here is a good link with the various improved chambers with increases from 100% for the standard 7x57 to 110% for the 30 degree and short neck version.

http://www.wildem.de/Improvs.htm

If you are looking for a light bullet that will hold up over longer ranges then you could de worse than to look at the 120gn GS Custom. I get 3235fps in my 7x57 with BL-C2 and 2700fps with the 160gn Woodleigh and H4350,so not sure the improved versionswould offer me more than 100fps and that (at least for me) is not enough to go past the superb 120 year old 7x57.

Von Gruff.

The bottom line for Ackley cartridges is the same for any. START LOW AND WORK UP!! This is especialy true for these cartridges since the only data ever publishied on them is outdated and it is well known that much of it is HOT!! Even Ackleys data for standard rounds is known to run well into excessive pressures.

A little common sense can go a long way with these rounds. On the average my max loads for my 257 AI tend to run about 2 grains of powder more than standard 257 +P loads. But it is notworthy that even with such marginal capacity increments that performance tends to increase substantialy because of a more efficient burn. The capacity difference is not that much, and when you do the math and increase beyond the % of the capacity gains, it stands to reason that you are entering into excessive pressure. Yes the straight walled case deals with pressure more effectivly, but ask yourself this question, how much excessive pressure do you want to subject yourself to?

Again you can achieve substantial gains with an improved case without a substantial increase in powder. A chronograph goes a LONG way with any wildcat. But with or without one, the first rule of reloading always applies, start low, work up and watch for the usual signs..

When working up my 257 AI loads a spike in velocity into the realm of "holy moly" was nearly always accompanied by a flattened primer. It is only rocket science if your trying to shoot the moon.

If I were loading for a 7X57 AI I would start with some modern 7X57 data that maxes out @ 50,000 CUP and not exceed more than 2 grains above maximum listed loads as a general rule, and there will be variation. But that is just me, YMMV..

Once more into the breach.

The 280 Remington loads in the Nosler #5 manual run approximately as such in a 24 inch barrel: 140 gr. bullet - 3102 fps, 150 gr. bullet - 2990 fps, 160 gr. bullet - 2892 fps and 175 gr. bullet - 2762 fps.

The 280 Remington case holds approximately 68.3 grains of water. The 7x57 AI case holds approximately 63.5 grains of water. Both cases where I measured the these volumes were Winchester brass.

The SAAMI maximum load is 60,000 psi for the 280 Remington because of the Remington Model 742 and 760 rifles.

The SAAMI maximum load is 65,000 psi for the 270 Winchester in comparison.

Now, if you run a 7x57 AI in a standard magazine rifle, you can seat the bullets pretty far out, because the magazine has loads of room and the 7x57 AI reamer has a long throat like the original 7x57.

With that 5,000 psi increase when used in a bolt action rifle, longer throat and only 5 grain differential in case capacity, don't you think that the 7x57 AI can easily equal the 280 Remington safe load maximum?

Answer, yes it can, and I've done it.

Now Reloder 19 does a decent job in getting you to those velocities in the 7x57 AI, but the primer pockets can get loose at the top end. On the other hand, Reloder 22 is the peach with the 140 and 150 grain bullets, whereas a compressed load of IMR-7828 works wonders for the 160 and 175 grain bullets.

P. O. Ackley's Volume I speeds for the 7x57 AI are spot on, but don't try it with IMR-4350. The new post Dupont IMR-4350 in my opinion and with first hand experience burns much faster than the older stuff.

Sincerely,

Chris Bemis

Von Gruff,

Thanks for the link!

With H4350 and Hornaday 139s in a VZ-24 I'm getting 3000-3100 fps depending on charge weight without any indication of over pressure. Accuracy is very good.

quote:

Originally posted by craigster:
With H4350 and Hornaday 139s in a VZ-24 I'm getting 3000-3100 fps depending on charge weight without any indication of over pressure. Accuracy is very good.

Dear Craigster:

Try the Speer in 145 grains, too. It is softer, runs out at a high 3000 fps, and is very accurate.

The Hornadys appeared harder to me, and caused a bit of a pressure increase when I used to load top loads in one of my old 270's.

The absolute worst pressure jumpers were the old Barnes X bullets.

Sincerely,

Chris Bemis

Dear Von Gruff:

Thank you for the link.

I guess the question becomes: "What is efficient for caliber."

I've set up ratio based tables of caliber and case volume and found the 7x57 AI to be just above the most efficient proportion of 7mm bore and case volume. Actually, the parent case 7x57 is a bit below the most efficient case volume, so the AI version is in my mind worth it.

Actually, the 280 Remington based upon my research is at the top, whereas the 280 Remington AI and 7mm Remington Magnum are over the top.

If you do it right, you can't overfill a 7x57 AI case with Reloder 22 for the 140-150 grain bullets or overfill it with IMR-7828 in the 160-175 grain configuration and still open up your primer pockets.

By the way I subscribe to Vernon Speer's interpretation of pressure. If I can't measure an expanded case head or find loose primer pockets after 5-6 reloads, who cares what the actual pressure is.

I keep accurate records of ambient temperature, bullet type, case, powder and primers for each of my reloading work ups. Coupled with Starrett and Mitutoyo micrometers to measure case head expansion and an Oehler 35 Chronograph, I have a pretty good idea of whats going on in the combustion chamber.

I've found that with Winchester cases in the 7x57 AI, when the primer loosens, the outside diameter of the head has usually increased anywhere from .0015-.002 inches.

The bigger problem today is that the factory brass has dropped to below minimum dimensions in my opinion. I have new 35 Whelen R/P cases that are only 0.4625" in diameter at the head. That is atrocious.

I'm trying to use Lapua brass whenever I can. They run around 0.470-0.471" in diameter at the head.

Sincerely,

Chris Bemis

quote:

Originally posted by Yale:
Now, if you run a 7x57 AI in a standard magazine rifle, you can seat the bullets pretty far out, because the magazine has loads of room and the 7x57 AI reamer has a long throat like the original 7x57.

With that 5,000 psi increase when used in a bolt action rifle, longer throat and only 5 grain differential in case capacity, don't you think that the 7x57 AI can easily equal the 280 Remington safe load maximum?

I dont doubt that everything you have said is true. I would just add a couple of points for those just begining with their new AI chambering.

-Seating the bullets out does not increase the case capacity, it just allows you to use more of the existing capacity.

-Citing pressures for the 270 may or may not apply depending on a number of variables, brass being the most notable. Take the 30-30 for instance. If it is chambered in a stronger action then it still cannot exceed SAAMI pressures because the weakest link is the brass. Is 7X57 brass designed to withstand the same pressures as 270 brass? I dont know, but I doubt it and I am sure that it is not all made equal. Now on the other hand if you take that same 30-30 and acklyize it you have altered the playing field because it removes 99.9% of the bolt thrust and the lionshare of the pressure is directed to the sidewalls, but the brass is still the weakest link! And their are no longer any SAAMI guidelines to work with. The same variable applies to the 7X57 AI.. Hence my call for discretion.

-I have no doubt that a 7X57 AI can "safley" match typical 280 velocities. They have been doing so for decades. I dont know about easily, lets remember that a 280 can be "hot rodded" as well. But the improved 7X57 is very efficient and very capable. I just want to point out that the same precautions and rules of load development still apply. No two rifles or two component combinations are the same.

I only mention this stuff because there seems to be two schools of thought on the webb reguarding most AI chamberings. One that you can now expect amazing results just because it is improved. And the other that anything AI is pure snake oil, they are unsafe and only a fool would even bother.

My view is somewhere in the middle. They do alter the playing field, but the same rules of reloading still apply.

Be safe and enjoy!