real data needed for 7X57 and now I have it.

Rumor has it that the reason their manuals list lighter loads is to keep the pressures in line because of this.
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Well that would explain some of the inconsistancies I have read. My Ken Water's bible does not show a load using H414 but it does show the load with W760.

Now this Savage was made in 1992. It would be a modern action. The twist is 1 in 9.5.
I like the 140 grain Nosler Accubond bullet as it has been great in my 7mm mag.

I have never heard of the rate of twist affecting pressures though.
 
jacky said:
I read quite a few threads regrading different loads and powders.

It appeared that with a 140 grain bullet H414 powder is the choice however in my manuals and on the internet there seems to be quite a wide range of results. If anything it means to work up the load carefully of course, but here is what I have found.

Now my gun is a Savage 24" barrel.

47 grains H414 - 2700fps

49 grains H414 - 2700fps - 2900 fps

45 grains H414 - 2700fps

Ken Water's and the Sierra loading books do not have a load using H414
and the Speer manual states that 47 grains with a 145 grain bullet is a compressed load.

Off the Hodgden site it shows 47 grains H414 at 2700 fps - 46000 CUP

Is 46000 CUP the max or can I go higher ?

So my question is has anyone acually Chrony'd their load or know what kind of pressures these loads are producing ? I want some first hand experience that way as I am working up my own load I will have a better idea what to expect. I fully plan on chronying my loads and working them up carefully as I am a nitpick for safety (and OCD for accuracy. ;))

Jacky
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Jacky, attempting to "magnumize" the 7X57 when there are high performance 7mm alternatives available doesn't make sense to me, even in a rifle with modern action. If you want .280 Remington velocity, buy a .280 Remington, a .284 Winchester, or one of the numerous 7 mags. While I am glad you are a "nitpick" for safety, I feel compelled to point out that any attempt by a recreational handloader to adjust his loads based on the published pressure is a dangerous thing to contemplate. For one thing, your rifle might produce higher pressure with that same load, but without a strain gauge it is impossible to say. The published pressure is simply there as a warning should you be using rifle which does not meet SAMI specifications.

Having said that, there are two ways that you can use your chronograph to determine the safe load in a modern rifle. The first is simple, beginning with the starting load from your manual, compare this velocity with the book velocity, then increase the load in one grain increments until you have reached the velocity of the maximum load suggested, or until you experience a sticky bolt lift. If you experience a sticky bolt lift, your maximum working load should be one full grain below that load. You can then work away from the maximum working load to determine the most accurate load, if improved accuracy is your goal.

The other way is to once again increase the loads in one gr increments from the starting load, watching for a velocity plateau. For example, if each one grain increment produces a 40 fps increase in velocity, then you observe a 15-20 fps increase in velocity, that represents a velocity plateau, and the next increase will invariably result in a sticky bolt lift. Thus the load that produced the plateau or even the load prior to the plateau should be considered your maximum working load, which you can work backwards from. This can be a tricky procedure if your ammo is not particularly consistent, as a large deviation in velocity can muddy the results enough to make the technique unusable.

Additionally, when I am working up a maximum load, I seat the bullet into the lands, as this condition results in higher pressure than when the bullet has a jump. As a result any changes I make to the OAL in an attempt to improve accuracy, works away from maximum pressure.
 
Jacky, attempting to "magnumize" the 7X57 when there are high performance 7mm alternatives available doesn't make sense to me, even in a rifle with modern action
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No this is not my intention. I just wondered about some of the descrepencies. I have a 7mm mag that is awesome. I use 62 grains of IMR 4350, get 3100 fps and the accuracy is unreal. I also increased the OAL as my Tikka seems to have a long chamber.

Having said that, there are two ways that you can use your chronograph to determine the safe load in a modern rifle
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No I don't really want to do that. The velocities I get are just that, the velocities using my gun, powder...etc. I just noticed quite a few varying numbers for the same load. I will get my own and post them so we can compare.

Additionally, when I am working up a maximum load, I seat the bullet into the lands, as this condition results in higher pressure than when the bullet has a jump. As a result any changes I make to the OAL in an attempt to improve accuracy, works away from maximum pressure.
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Like I said above I do this too. I have found the accuracy to really improve.

Thanks for the ideas. Maybe a few of us should take some data on our loads and post them here. This seems to be a popular handloaded cartridge.
 
I have a slightly different take on this. I think the cheapest thing in the reloading kit is the chrony. I always use one when working up loads. I have seen huge variation from the predicted velocity, usually lower. I like to take a hand press to the range and see how many times a case will fire before splitting or stretching, or the primer pockets getting loose. To me that is the only real measure of pressure in the safe range. It is easy to tell if your loads are waaaaaayyyy too hot, or way too cold, but with a little experimentation you may find that giving up as little as 50 fps give much longer life. And 50 fps never killed anything, or failed to kill it. I use bulk powder that I bought from Tom Higginson, and I work up my own loads. Some exceed predicted velocities and some do not do quite as well. Every reloading book says that every rifle is an individual, and you should work up a load for it. I am not hung up on stopping where the book says, either in velocity or charge, but this is based on good research with my individual rifle. If you are not willing to do the research, then by all means, forget you ever read this. But if you have proven to yourself that you are able to reuse a case 10 times with no problem, or just a slight trim, and the primer pockets stay tight, then you can be comfortable with your load, no matter the velocity. I like slow burning powders for rifle cases, as they are the most forgiving. I load for a 93 mauser 7x57, and I shoot 175 grain speer mag tips at about 2300 fps. It is severe poison for moose and deer.

My two cents worth...
 
In a modern action, the 7x57 is a very respectable performer that responds well to slow, or medium-slow burning powders. These include W760, H414, the 4350's, IMR 4831, H4831, Norma MRP, N204, Vihtavuori N160, N560, Alliant RL17, RL19, RL22. plus a few others. I have owned and loaded for at least a half dozen modern 7x57's, and have come to the conclusion that the maximum practical velocities with a 140 grain bullet in a 22" barrel is right around 2900 fps. With the 150 it is about 100 fps less, and with the 160 about 200 fps less. For example, I just finished working up a load in my 700 Classic in 7x57, using the Chinchaga 155 grain bonded bullet. With 51 grains of Norma MRP, this load chronys 2720 avg for 5 shots, with no adverse pressure signs. The groups were not spectacular, but very huntable, at 1¼moa. I would consider this load to be effective on all non-dangerous North American game. As has been said, If you need higher velocities, buy a rifle with a larger case capacity. Regards, Eagleye.
 
There has been much press in the past suggesting that the 7x57 was a "ladies rifle", or suitable for a man sensitive to recoil. It is easy to forget just how effective Eagleye's 155 grain bullet is at 2720 fps. And inside say 300 yards it is plenty flat... It is a big rifle to the guy I know who hunts moose with a .243.
 
It's been a few years since I loaded for the 7x57 (mine was tang safety M77) but I realized the best results from IMR4350 for 140 Partitions and 162 Hornady BTSP's, W-W brass and CCI 200 primers. The 140's averaged 2,828 and the 162's just under 2,600 which were right at book values. Obviously everyone's results are different because I couldn't make 760 or H414 work to save my butt. The burn rates on these three powders are very similar and are right in the wheelhouse for the 7x57 making them all excellent candidates to try. I read somewhere that 760 and H414 are in fact the exact same product (both are made by Hodgdon). I wish I could remember where, something tells me it was a post by a gunwriter on an American forum - maybe other more enlightened members could clarify.
 
One thing that never seems to be mentioned here, is the variances of any given powder, from one lot to another.
More years ago than I like to admit to, I met Elmer Keith. He was pleasant, outspoken and crusty, all in the same sentence and reeked of his ever present cigar. He was disgusted when I told him I wasn't armed and even more disgusted with Canadian law, regarding firearms. He didn't hold it against me. He was also a walking encyclopedia. He pointed out to me that the information listed in loading manuals, usually left a lot of room for potential, because of the variable conditions of firearms used, temperatures while being shot and even elevation differences. He also informed me that every batch of powder had a different burn rate, even though it carried the same description. I was a bit sceptical about this but who the hell am I to tell Elmer Keith BS? Well, he was dead on the money. Old Tom Higginson informed me that it was only good common sense to realise that all manufacturers have "manufacturing tolerances". The powders listed in those manuals will be safe, within those tolerances. Each lot may be very similar but will react differently from the next. That's why I prefer to buy powder in quantity, like 8lb kegs. Another good little trick, if you can't get a keg, is to take 5 each, 1 pound tins and pour them all together into one container and "blend" them. This will give you a decent supply of consistent powder. Same goes for primers. By them by the carton of 1000, rather than 100 at a time. Again, consistency is the reason.

Now, because of Tom Higginson, I got to talk to a Hodgdon rep. I brought up the age old argument about consistency from batch to batch. He agreed with Tom and Elmer. He even told me that things may be worse now than previously. It turns out that powders are made all over the world, usually by availability of production facilities but also to the lowest bidder. The basic ingredients of most powder is the same, the real difference in burning rates, is due to the coatings which regulates burn rate. This coating, again, is made to "manufacturers specs" and have + or - tolerances. The nasty little surprise comes when, you get a lot made to the lower end of the specs and another made to the top end. Not enough to be dangerous but enough to effect accuracy, in some rifles.

The 7x57 isn't any different from any other cartridge, when it comes to powder variation. If you shoot the same rifle a lot, you will know what I'm saying. One lot of powder will act differently than the next. We won't even go into the variations between primers, cases, bullets, chambers and barrel dimensions.
 
Bearhunter, I could not agree more. I remain convinced that the best reloading tool is the chrony. No one really knows velocities without measurement. It would be nice to think that the numbers Mr Nosler, or Mr Hornady, or Mr Speer, or Mr Lee, or any of the others would be accurate in my rifle with my lot of primers, powder and bullets.. But they just are not going to be.
 
I also agree 100% with Bearhunter on powder variances from lot-to-lot. I, too, buy in larger lots to eliminate the load development needed each time I start using a new lot number of a given powder. FWIW, some powders are better than others in this respect, but any of them can show the problem. Regards, Eagleye.
 
H4831, 48 grains, Win primer, Rem brass, got accurate right there. Start load is 47 grains, max is 49.5. This is with a 139 grain SST. The Lee book says velocity goes from 2592 to 2719 fps. Not much spread for 2.5 grains of powder but is very close to the 50 fps/grain mentioned. This is a large kernel powder that is not as accurate out of a powder measure. That load operates the action on an FN49 OK.
 
Speer reloading manual number 7.

In the manual the bullet size jumps from 130-145 no 140's listed, but for 145gr bullets the load info i have is much hotter than others listed here, for instance in the post above my last one snomad lists 49.5 as a max load, 4831 powder.

The starting load i have for 4831 is higher than his max load, with a heavier bullet 145gr

4831 powder 145gr spitzer

Start load 50.0gr 2613 fps
mid load 52.0gr 2782 fps
max load 54.0gr 2890fps
 
Crazydave; That sounds like an older Speer manual. Many of the loads in the Speer #8 were quite warm, some so warm you could not use the listed max load in certain firearms. Be careful that you approach any of these from below cautiously. That being said, I have shot 54.0 grain of H4831 behind a 140 grain bullet out of a 7x57 without any incident. The accuracy left something to be desired, so settled on 53 grains of Norma MRP, which gave up little in velocity and was very accurate. Regards, Eagleye.
 
Thanks Eagle eye i always work up and proceed with caution, usually warn others to do so as well.
Although the manual for some calibres lists lower charges than other manuals for some reason, i guess at that time those calibres were the ones known to have weak actions.
 
Ok here is the Data I promised. I was using PPC brass, Winchester Magnum primers and a 140 grain Accubond bullet and my gun has a 24" barrel (1:9.5 twist). The temp was 23 deg and cloudy. I tested two powders chrony'd 5 shots with each bunch shot and then took the average. Here is what I found.

IMR 4350

47 gr - 2745 fps
47.5 gr - 2801 fps
48 gr - 2823 fps

H414

47 gr - 2695 fps
47.5gr - 2746 fps
48gr - 2754 fps

Now I seated the bullet to give me a COL of 3.09 " which is a little longer I guess but I did not shoot one group that was outside of 1 1/2". In fact most groups were under 1".

I liked the 47 grain load with IMR 4350 because that group was tight. I will probably use that load this year for hunting.
 
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