Home Forums Reloading Big Game Rifles Powders for 7x57 Mauser

First, thanks to all that have helped so far on all my reloading questions!

Next, what powders should I be looking at for loading my Mauser? I have IMR 4350 and understand it may be temp sensitive. I also have Varget on hand. From what I'm reading on here and in articles, this may not be the best for the 7x57?

It looks like W760 should be on my short list.

What others and why?

Thanks again.

H4350, Ramshot Big Game and RL17 are worth considering especially with 140gn & 150gn bullets

Add IMR4451 to that list.

If temp sensitivity is an issue then skip the W760/H414.

The 7x57 is at a case capacity to bore size ratio where the optimum class of powders will shift with bullet weight.

Well, I'm not positive it is. I've just been loading with imr 4350 because that's what I have. And almost all the reloading data shows it in their manuals. That's the reason I got it to start with.

Sounds good. Any particular reason or you've just had good results?

It seems to like 139/140gr pretty well so far.

IMR4451 and H4350 are temperature insensitive powders suitable for IMR4350 friendly applications. Both go through a powder measure better than the IMR version.

How about RL19? I see that listed quite often as well.

Bad temp sensitivity reputation.

Any non-industry tests on IMR4451 that show it is in fact temperature insensitive?

I don't have any tests. Is the claim suspect?

If your google fu is strong you can find a couple on the web comparing the two. Those I have read indicate that 4451 is not as insensitive as H4350, but not too far off and certainly better than, say, IMR4350. BUT those I have read are flawed in that they only chill the ammunition, not the rifle.


Tzone, as I mentioned in the other thread, try H4831 with heavy bullets.

I had to read that twice,but it's true,I think.

I won't use Winchester powders in general -- bad temp sensitivity. Exception for me is 296 AKA H110 -- I use in 44 mag.

IMR4350 is less temp sensitive than 760, I believe. H4350 is probably better yet. IMR4451 is also good.

Thanks guys! I really appreciate it!

For example, you'll see a bigger shift in optimum powder moving from 120 to 175 grain bullets in 7x57 than you will moving from 125 to 180 grain bullets in 308 Winchester.

I've had good success with 140 to 150 gr bullets and a case full of R19. Never did any serious testing for temperature sensitivity, but shot deer, antelope and elk under all sorts of conditions with no problems. Had a great 120 gr load with IMR 4007, alas it is gone. My 2 rifles are not very sensitive and shoot well with a variety of powders. H4350 is tough to beat for an all around powder. H4831 is also useful.

Just skeptical of manufacture advertising hype. Would like to see hard data.

I purchased 4451 to try in my 7x57s because ran out of my H4350 supply. It did not approach the accuracy of H4350 in three bullet weights, 140 150 and 160. IMR 4350 was better with 140 and 150 grs but not as good with 160 gr.

I haven't messed around much with Big Game yet, but Hunter seems to perform well with 160- and 175-gr bullets. I expect it will do well with 154-grain Interlocks as well, which I plan to test once Hurricane Irma gets through with us. As for temp sensitivity, most of my shooting is in temps in the upper 80s and low 90s, down to maybe the mid 40s. Someone else can speak to this, but I don't think that's enough of a spread to matter much.

RevMike

What is the loading range (start/max) for 160-175 bullets with Hunter?

Good morning from breezy Florida.

I posted this a while back on the "Good 7x57 Loads" thread, but below is Ramshot data for both Big Game and Hunter. At this point I haven't done much of anything with 154-grain bullets - I'll get around to it - but the 160s at an estimated 2550-2600 fps, and the 175s at about 2350-2400 shoot very well in both my Montana ASR and M98. These velocities are estimates since I haven't run them through a chronograph yet - I'm waiting for a bit of cooler weather - but they ought to be close in 24 inch barrels. The 160s are Speer Deep Curl (n.b. I use the Deep Curl data on Speer's site just to be on the safe side), Grand Slams, and Partitions. The 175s are Deep Curl and Grand Slam. All shoot right around an inch at 100 yards off the bench. They might do better, but the reticles on the scopes are German 4s, and both are thick enough to cover a one inch target dot at 100 yards. So I'm not getting "target precision" even if I was good enough. But it's good enough for my hunting purposes. Once the 175s are gone, I don't expect to replace them, and will probably stick with the 160s and 154s at about 2600. Again, most of my shooting is at game, so those bullets at those velocities should do anything I need them too. Our deer aren't very big, and even though I've taken some really big porkers, most of the ones I shoot are table size - way less than 100 pounds - all generally within 75 yards, and all either CNS shots or not shot at all.

Anyway, that's all reaching around my butt to scratch my elbow. Here's the data I think you're looking for.

IMO, H4350 is where to start with the 7x57, and especially with the 140-150gr bullets. When it comes to temperature sensitivity and IMR 4350 (and actually most powders), I usually ignore that notion. As long as you develop a load that's safe in the summer, it will be fine in the winter. And, it will hunt just fine too. In my personal 30/06, I use IMR 4350 with 165s. I try to avoid shooting in the middle of the summer, but even early fall where I shoot it's often over 90 degrees in the morning. Last buck I shot with that load was on a 16 degree morning, and at 200 yards that bullet landed exactly where I intended. Your mileage may vary, but I doubt it. Getting back to the 7x57, if 4350 doesn't work in your rifle, W760 with something in the 150-160gr class of bullets works well. If you are a max load type of shooter, I FOR SURE would develop a load in the heat of the summer with that powder. It will be safe in the winter, but not always the other way around.

One more note about the 7x57 - don't ignore the "in-between" bullets. People tend to shoot 140gr or 160gr in 7mm, and sometimes 150gr. I had a finicky 7x57 that shot all those bullets decently, but dropping a 145gr Speer produced clover leafs. Same with the 154gr Hornday - not quite clover leafs, but more consistent that the 150 below and 160 above. Good luck!

I have to wonder about that. Most of my load work ups have temps running anywhere from 80* to over 100* I have a neat load for a 30-06 pushing the 165 gr. Accubond close to 2900 FPS at 100*F. I used that load on my last elk hunt in New Mexico and took a nice cow elk at a bit over 100 yards. The temp in the truck was 6* above zero. The day before when checking my sights and figuring I might have to adjust some, the point of impact was unchanged. Temp was 14*F above zero.
I've had similar results in the .270 Win. and .300 Win, Mag. using WMR powder. (Winchester Magnum Rifle) Same with Re15 in my .35 Whelen.
The only rifle than showed any change in POI was my .280 Rem. using WMR and IMR 7828SSC but even then the change was very small. So far anyway W760 and the others have worked nicely for me.
Paul B.

Thanks RevMike.

Just my opinion but unless you hunt the world from northern Canada to the equator or are prone to firewalling every load to just short of locking the bolt up on your rifle the temp sensitive issues is overstated for the average hunter/shooter. I have reloaded for 45 years and used many of the now dreaded temp sensitive powders such as ww760, Blc2 . 4064, ,4350, 4831 and never really had any issues. Now I mostly hunt in Kentucky and the temps range from a high of around 90 in the summer to a low of just above freezing for in the fall but I nor the groundhogs and deer ever noticed the velocity fluctuation. Accuracy never suffered enough to notice. I'll admit I did do most of my load development in the summer not by plan but mostly because it was the off season. Use your 4350 and if it works for you well enuf said.

I agree 100% I've used double based powders like W760 & W748 for the last 25 years in all types of weather and never had a problem. In my opinion, the only time you'll ever have issues is if you left your ammo on the dashboard on a hot summers day. But nobody in their right mind does that anyway.

But I hunt in CO where the temp can range from 90's to as low as minus 20-30 degrees. I have hunted in -10-15 degrees in fourth season. We also are more often presented with longer range shots than in KY where temp sensitivity can be an issue in changes in POI. I don't worry too much about temp sensitivity when hunting varmints such as coyotes since I do that mostly in the spring and summer as I hunt public land and don't want to interfere with big game hunters.

I'm currently not real concerned about it since my shots will be 150 yards or less for this season. But It's good information IMO to keep in mind.

Temperature-sensitivity issues can and do occur, but not always, even when there's a considerable change in muzzle velocity. Some rifles are far more prone to point-of-impact changes in cold or warm weather with temp-sensitive powders, particularly those that tend to change POI noticeably with different powders charges when working up loads. I've seen POI changes of up to 3 inches at 100 yards when shooting the same load at 70 degrees Fahrenheit, and then again at zero F. That isn't common, but it can happen, and I've seen 2 inches quite a bit.

Of course, 2-3 inches at 100 won't make any difference on the ribcage of a deer or elk. But it becomes 4-6 inches at 200 and 6-9 inches at 300.

One of those pesky gun writers recently wrote an article on this what will be published this fall in some magazine. For those who don't read magazines, the basic point of the article (which is based on considerable shooting at different temperatures) is that, yes, most of the time temperature-sensitive powders don't make any difference, especially when shooting at big game (which is by definition big) at modest ranges. And yes, it can make a difference in some rifles, with some loads, in some conditions--but to assume that it never makes a difference might result in a surprise someday.

Most humans are quite fond of "examples of one," especially if the example agrees with their point of view. But examples of one, such as shooting an elk at 100 yards in cold weather, don't prove anything.

Thanks MD.

Thanks MD.

Really, the only reason I'm not concerned with it is because I'm shooting at 150 yards and under. Probably a lot under. I will be on the lookout for some of the powders that are resistant to the temp change. I tried this weekend and was unsuccessful...I figured there was a reason for that.

Thank you for the help on this subject. It's much appreciated.

I get good results with 42-44 gr IMR 4320 and a 140 gr Ballistic Silvertip, (41.5 gr behind a 150 gr Part. in the 7mm-08 is what I hunt cow elk with). A charge of 46 gr of IMR 4064 and 120 gr B-tip is my go to lope load. From a 21" barreled 98, they all shoot under an inch at 100 yd and have the same point of impact.

John,
Those rifles that changed their point of impacto so much when shooting at different temperatures, would also change their precision, or does precision tend to stay the same?
Thank You,
Alvaro

Have you by chance checked the velocity on these loads? Reason I ask is because I recently got a 20" barrel carbine and the greatest loss from factory loads was only 42 fps less than from my 22" barrel Mauser but, one of my handloads was 130 fps slower. This 65 fps per inch of barrel puzzles me.

When I started working with 4320 in the 7x57, 45 gr would give me 2730 fps with a 120 gr Hornady SP. I left it at that as that's about as fast as I wanted to drive a "varmint" class bullet for antelope. The 46 gr 4064 load gives 2880 fps with the 120 gr Btips from my 21" tube and it is lights out on antelope out to 230 yds. These are 10% reduced Ken Waters' Pet Loads so I have a few grains to play with using 4320 & 4064 with the 120s but have never found the need to. In Pet Loads he lists 45 gr of 4320 as a Max load for a 140 gr Solid Base at a velocity of 2885 from a 22" barrel. I reduced that 10% and worked up to 44 gr, that's where I was comfortable with the brass and primer combo I was using and I suspect they might be running about 2800 but don't know for sure.

It must be Easter season; another old thread resurrected.

Mathman, how do you know then which powder to use? For instance, in the Nosler manual, the 7-08 data shows a switch from Big Game to Hunter at 150-grains, while in the 7x57 data Hunter is recommended for all loads. When would one know when to switch? I don't know if that question makes any sense, but I'd like to find one optimal powder for all C&C bullet weights from 150- to 160 grains, inclusive, pushing them at MD's magical 2700 fps, if there is one. Based on your comment that the optimum class of powder will shift with bullet weight, and knowing that there are at least four common bullet weights between 150- and 160 grains, it looks like there may not be.

I'd say the 150-160 range is well covered by H4350 and IMR 4451, and one of those is what I'd use first. I'm not familiar with the newer Reloder powders though, so I may be missing something there.

Am I correct in assuming you'll be loading for rifles that can handle modern pressures?

Thanks, as always. I have about a half pound of H4350 and a jug of the IMR version. Now that the general hunting seasons are over I'm going to try to work up a load for a cantankerous M70 using 154-grain Interlocks. It doesn't seem to like either Big Game or Hunter. I'm curious to see what JB's upcoming article has to say about new powders in the old cartridge.

Thanks again.

I`ve had very good results with RL 17 in mine...from 140`s to 162`s.

I have a Mod 70 Fwt. 7mm Mauser enroute. Missed having one or two in the safe. I will start with H4350 and the 150 BT, work into the Acc. and the Partition. I have the old MD story on the Mauser and frequently gone back to re-read it.

I have the M70 FWT and I've had excellent results with Re17 and the 150 gr. Partition. I'm not going to post loads as they're well past any published book loads. All I will add is they're safe in my M70 and Ruger #1A. Not so in my custom rifle based on a commercial FN action. That rifle shows high pressures much faster than factory rifles.
Paul B.

MD has written quite a few times about using your reliable chronograph to tell you when to stop.

My Winchester xtr only like H4831 for some reason. Does well with 130's and 140's.

H-414 works great with 154's for me. Even with temp sensitivity, the cartridges I've loaded with that powder have never let me down. Most of the shots with that carbine have been at woods ranges and one or two long shots (around 200 yds). All the deer died and were collected.

Dan

Ramshot Hunter out shot H4340 with 120 and 140 Ballistic Tips. Plus it meters like a dream.

The new Fwt. 7mm Mauser arrived today and getting it prepped for an eventual range trip.

Thanks, PJ for your report.

I have burned a bunch of AA 4350, IMR 4350, WC 852 and H414 in my 7x57. My shooting seldom goes past 250 yards and the temps I hunt in can vary from 10 degrees to over 100, I have never had temperature sensitivity of a powder make the slightest difference on any shot I have made. Come to think about it that rifle has had many pounds of powder run through it.

I decided to see just what results I might get in my Custom Mauser with Re17 and the 160 gr. Speer Hot Core. Thought it might be a nice load for a cow elk hunt.

First I had to find a source of data as none of my manuals have much on Re17. I sent Speer an E-mail and they came though giving me a place to start. Then, using a set of data from a Quickload search a friend did for me giving me an idea of when I should quit. I got to the ranges yesterday and ran 12 loads from start to where I thought it would be a good idea to quit. I couldn't use my chronograph because it was acting up with weird readings. Load #10 was where I felt it was time to quit as bolt lift on load #11 was quite stiff.

This rifle usually shoot MOA or better with factory ammo so the disaster this groups of test loads surprised me. Best group was three inches. Worst was close to six inches. WTF?

I was out in my shed early this morning checking screw tightness, the muzzle's crown, you know, all the usual suspects and everything checked out good. I would have gone out today but it was a bit windy than what I care to shoot in so just worked on the brass and cleaned the gun. Gonna be windy the next few days so I'll probably just load another test series with the bullets seated a bit deeper. I had this batch just off the rifling.
Paul B.

Paul:

When you get a chance, please post an update. I'm mostly curious about the bullet and how it shoots in your set-up.

Thanks

After thumbing thru this thread...

I still go back to using two bullets in my Featherweight, with a factory barrel..

139 grain Hornady or the 140 grain Ballistic tip...

and two powders with those two bullets... IMR 4895 or 4064.. both with 44 grain charge..
chronographs right on the money at 2800 fps...

if the rare occasion I use a 160 grain or 175 grainer.... the load is 40 grains of 3031..
got that out of an older Hornady Manual...that turned into the magic powder for a Ruger 7 x 57.
velocity is higher than the Hornady manual says it should be...but its accurate and the rifle or brass don't seem to care...

Seafire, what does the Hornady manual say the velocity for 175 grain bullet should be, and what velocity do you get with 40 grains of 3031 in a Ruger 7 x 57 with I assume a 22" barrel?

PM is being sent...

I`ve been shooting RL-17 and the 162 ELDM`s in my 7x57. Excellent accuracy at 2750FPS to 300.
Anyone using this combo in their rifle?

I loaded up another test series using RL17 and the 160 gr. Speer bullet, There will be a few differences for this test. First all new Remington brass as the rifle used will be my M70 Featherweight rather than the custom Mauser. Second, I'll use the same seating depth for the M70 and third I'll use the chronograph for this next run. I probably should have changed the seating depth and do them in the Mauser but I'm curious on how the M70 handles that load. Now I have to wait or a day that has decent weather like little or no wind for a few hours. Looks as if next Wednesday is a possibility as Monday and Tuesday are forecast to be a bit breezy to windy.
Paul B.

I may have to try 175’s if I can’t get the 154’s to shoot well. Maybe I’m being to picky.

Rev. Mike. I hope this gives you what you want.

Well the weather forecast was for calm winds becoming light and variable in the afternoon. Yeah, sure. Got to the range and it was blowing 8 to 10 MHP easy. Temp was about 65* and the wind felt cold. I'm wearing a tee shirt and jeans.

I had ten sets of three rounds starting with 42.0 gr. with a half grain increase on up to 48.0 gr. Speer's max for the 160 gr. Hot Core is 44.0 gr. Before I go any further, this was in my rifle and nothing gave way. Results were if nothing else a bit on the weird side as will be explained. Sad to say these loads were tested in my FN Mauser and this M70 without my normal use of the chronograph as the last time I used it it gave very erratic readings. Just haven'y gotten down to sending it in for repair.

Load #1 Triangular group about 1.25x"3 5/8". Primer nice and round.

Load #2 Group is 1 1/16"x 1/16". No change in primers.

Load #3 Group 1 1/2' x 1/2" Primers round with slight cratering. (I should note that even the mild Winchester 145 gr. ammo shows mild cratering in this rifle.)

Load #4 Group 1 1/2"x 1 1/2" perfect triangle. Very slight flattening, no change in cratering and edges still nicely rounded.

Load #5 Group 1/4"x 1". Primer no different from load #4.

Load #6 Group 1"x 1 1/4" No change in primer flattening and no cratering.

Load #7 Group 13/16"x 3/8" Primers still with rounded edges and slight cratering.

Load #8 Group 3/8"x 1 3/8" Primers still have nicely rounded edges. slight cratering on one case only.  

Load #9 group 3/8"x1/2" Primers slightly flatter than previous cases. Cratering definitely more noticeable but not much different than what I've seem in factory .270 Win. and .300 Mag loads.

Load #10 Group 2 5/8" x 2/3/8". Primers flattest so far with still slight rounding at the edges. Cratering quite noticable.

Rifle Winchester M70 FWT, brass brand new Remington, flash holes reamed, trimmed and primer pockets uniformed.
Wind out of the east 8 to 12 MPH estimated, temperature about 62 when starting and 66 when done.

Target was a black 2.5"x2.5" square with a 1.0" white square in the center. Odd number shots were on the lower left hand corner and even numbered shots on the upper right hand corner. No effort was made to bring the scope into line with point of aim as the rifle is sighted in for a good load with the 150 gr. Nosler PT.

Interesting thing is shots on the lower left corner always seemed to me much better than when the upper right corner was used as the aiming point. I've used those target for more than twenty years and this is the first time I can recall that happening. It's also interesting that the FN Mauser showed pressure at load # 5 vs load #7 or 8 depending on how you look at it in the M70.

All in all an enlightening day at the range.
Paul B.

Very interesting, thank you. If what I've read is accurate, your most promising loads are No 4 and No 9. For No 4 it's an issue of just tweaking the seating depth. It looks like No 9 is already there, albeit with a bit of pressure signs.

That seems to be about it. Quickload estimated velocity for #4 was 2546 FPS and for #9, 2697 FPS. There was one other difference that I think I forgot to mention. The loads for the Mauser had IIRC Winchester primers and the M70 I used CCI primers, only because that's what was in the new cases. I read somewhere just the other day that CCI primers had softer cups than Winchester which could explain some of the cratering. However, I really have to get out and get more powder, My supply of Re17 is very low. I already have a very good load with the 150 gr. Nosler PT for the M70 and I'd like to see if the FN Mauser takes to that load as well. I'll be staying as far away from the range as possible with it being the Memorial day week end and all the mall ninjas and Rambo wannabes will certainly be there. That means I won't be.
Paul B.

No.9 also is right at MD's "magic" velocity of 2700 fps. With that velocity and accuracy, that might just be your hunting load.

I found a box of test load I made up probably about three years ago. The load was 47.0 gr. Re17 and the rounds had either the 150 gr. Nosler Partition or 150 gr. Nosler ABLR. Half the loads with each bullet had Winchester brass and half had Remington brass. I remember making up the loads for the M70 and had planned to shoot 3 shot groups and then using my Lyman tong tool seat the next three a little deeper and so on. My mistake was I forgot to take the tong tool.
I also took my 257 Bob out with me today. I had a few rounds loaded up with the 100gr. Barnes TSX. IIRC, they were running around 2900 FPS. Not one round hit the paper or the backer. I shot one at a rock on the berm with a fellow spotting for me and he could not see where the bullet hit.

Next plan, quit shooting and take up something simple like quantum physics . Not really. Two things up front. Clear all copper fouling from the barrels. I have a load for the M70 with the Partition. Why that rifle was all over hell and gone needs to be addressed. It dies tend to copper foul a bit so that'll be the first step.check all screws, you know, the usual subjects. Do the same with the .257 Bob plus do a bore siting while I'm at it. Tried to do a bore site at the range and due to the small bore didn't get anywhere. I think next I'll do a pressure work up for the Mauser with the ABLR. That damned bullet looks just too good to not shoot well. Come to think of it, I also have some 120 gr. and 140 gr. TSX bullets for the 7x57. I have gotten the 140/TSX up tp 2800 FPS but lousy accuracy so far. I notice that Barnes shows that 140 gr. TSX bullet to be good for elk in the 140 gr. weight. I think I used H4350 with that bullet years back. Gonna see how Re17 and it get along. So many choices.
Paul B.

Lots of good advice here on bullets and powders. When I get time to begin test the Fwt. and Mt. Rifle, I'll start mid range at 140-150 with H4350.
Its good to have a couple in the safe.

Decided to pull my old beater Mauser out today and shoot up some old reloads. It was scopeless so I put a Leupold M8 4x on it. I had 4 boxes of 7x57 ammo loaded with the 150 gr. Ballistic Tips powdered with WC 852 that I had put together back in 2014. Well 4 5 shot groups of 3 inch suck I found my action screws were a half turn loose, both of em! Tightened em up and went back at it same crap! So I decided to thoroughly clean it using Turtle wax chrome polish and a tight patch. Ran that in and out 4-5 times and then cleaned the residue out with clean patches. Went back out and immediately was back in business. POI had dropped to the 4 oclock position, first two an inch apart, 2nd pair touching and last three shotter 2.5 inches high, centered and right at an inch. Now the wind was heck 20 to 35 MPH gusting and shooting was a sporting proposition so I quit while I was ahead. So now I have more than 40 empty pieces of brass and some 160 gr. Partitions looking for a home hmmmm. Think I will load some up using IMR 4350 and play some more tomorrow.

Good idea using the chrome polish....never thought of that. May have to try that. Good to hear.......good luck with your 160gr Partitians.

I found upon inspecting the fired brass that 1 in 4 had split necks! Much of this brass had been fired plenty of times before. My "new" brass collection resides in unfired factory loads, Federal, PMC, Remington and Winchester collected long ago so I guess I am going to pull the bullets and dump the powder from that to load the Partitions in. No shooting this weekend as I am covered up with family for Fathers day.

I agree and H414/W760 is a great powder in the 7x57 with 140-160's. I have shot so much game with this rifle/powder combination that I wouldn't even guess how many, temperature sensitivity doesn't worry me much, it's a hunting rifle, not a 1000 yard match gun.I just work up a load when it's 100, so I know it's safe, then hunt with it.

Safety is not the sole concern re temp sensitivity.

I've used RL19 for many years in my 7x57. With a 140 grain Nosler Partition, it shoots excellent groups and performs well on whitetail deer.

I'm aware of that. I have always worked up loads that didn't change impact with relatively small changes in powder charge/velocity before the words 'nodes' and 'ladder tests' existed. For the most part, with a hunting rifle, it's a non-issue.

Finally got a decent day to go shoot. Ran a double test with Re17, One set was with the Nosler 150 gr. Partition and the other with the 150 gr. Accubond Long Range. I started with 44.5 gr and went up in 0.5 increments to 47.0 gr. which had shown good accuracy in an M70 FWT. Rifle is a custom based on a commercial FN Mauser action. Cartridge of course was the 7x57. The first loads would usually put two within an inch and then blow the third out of the groups. Actually the flyer could be from any one of the three shots. One load, #4 IIRC put two touching and blew the third shot 4 1/2" to the left. Vertically if it had stayed in the group it would have been a .250"x.375" group. Bullet was the Partition. After that particular set groups went haywire and scattered. Was it the loads? Scope? Something get loose in the scope mounts? I even had some of the ABLRs put two nearly touching the a shot out of the group. At the start I allowed a timed two minutes between shot and by 0830 it was starting to get hot so gave three minutes between shots. Once the temps get near 100 even a ten minute wait won't let the barrel cool very well.

My other two 7x57s were easy to find great groups but this Mauser is driving me sane.
Paul B.

Got an old '96 Mauser 7x57 for my son's 13th BD

Started working loads, more interested in lighter loading with accuracy.

45gr of 4350 with 140gr BT or 145gr Win SP

Outstanding accuracy and 9 deer later, I see no need to change.

Took the rifle out, last season. Grandson turned 13. 145gr Win and deer dropped in its tracks @185 yards, makes a happy boy.
Less than hour later, 140# hog @ 130 yards met the same fate.

Well the next batch of tests for the 7x57 should start tomorrow. I'm just gonna run the 150 gr. Accubond Long Range at different seating depths using the load that was the last one before starting to see pressure signs. I should have made a same set using the 150 gr. Nosler Partition but the heat drove me out of the shed where I do my reloading. Brass will be the well used Remington that I started with, CCI 200 primer and 45.5 gr. of Re17.

The rifle was a J.C. Higgins M50 in .270 Win. so I'm not worried about the strength of the rifle. barrel is a 23" Douglas that showed to be quite accurate shooting Winchester 145 gr. factor ammo on that same rifle. When I did a test run using the same load in a Ruger #1, Winchester M70 FWT and this Mauser running the 175 gr. Hornady round Nose, the Mauser averaged 150 FPS faster than the 2315 Average from the other two rifles. This rifle has an extremely tight chamber which just may be the source of the higher pressures. I just don't know. I do know that so far, the 150 gr. ABLR has not been accurate in any of those 7x57s nor in a custom .280 Remington.
Paul B.

Paul:

Thanks for the update. JB has mentioned that in his experience some 7x57s just don’t like boat-tail bullets. Any chance of loading a 150-grain flat-base?

Mike

Yeah, I guess I'll know tomorrow. I get decent results with the 150 gr. Nosler Partition so I'm good there. I can push it to 2900 should OIO feel the need and as a matter of fact that is the most accurate load in my M70 FWT . I can't say what they'll do in the Mauser so I'll have to do a run with those as well. I got a bit of a late start this AM so by the time I was done with the ABLRs it was way too hot to keep on keepin' on.
Paul B.

I just gotta wonder about all the angst and drama over the selection of temperature sensitive powders. Sure, if you know you are going to be hunting in Sonora on the 4th of July, you may want to step your charge weight down, if you know you are going to draw a wildebeeste tag in Cut Bank Montana in January you can stoke 'er up pretty good...but good grief, has it occurred to anyone that we have loaded the '06 and 7.62 with funky old blc-2 and H380 for eons? Korea and eastern Europe to Africa and SE Asia.... c'mon guys, you are going to extremes (pun is the lowest form of humor).

Oh my. Going to an extreme? I think not. I may not hunt in Sonora and I do most of my reload experiments right here in the Sonora Desert but hunt in New Mexico when temps can be as low as 4 above zero (been the and done that)so yes, working with powders that that may give problems due to temperature extremes is something I look closely at. I'll be doing some load testing tomorrow and it's forecast to be around 100 so I'll be working in the upper 80s to lower 90s during the time I'm there. FWIW, it was 4 above zero in the late afternoon when I shot my elk last year. The late Elmer Keith once said, "I believe every man should scratch his own fleas in whatever manner he chooses." I think the same should work when deciding on powders for handloads.
Paul B.

PJ....in your post on page 2 you said you didn't notice much difference in poi. Which was kinda, sorta my point. But you are dead on right, powder choice on your bench is a matter of personal preference. When a poster asks for input from other's experience here, I don't think any of us try to lead him astray. I was merely pointing out, in my flawed communication, that the military felt quite comfortable loading millions of rounds with ball powders for a variety of climates. My position is, perhaps we are overthinking temp sensitivity...any small change in MV is generally overshadowed by the variables in shooting game animals offhand at varying ranges. Admittedly, the new trends of long range sniping of game animals may benefit from more stable powders.

Sometimes the changes in velocity cause differences in POI other than vertical.

Flintlocke, I get your point. Problem is the military standard for accuracy from the average rifles isn't looking for sub-moa grouping, just minute of man type accuracy.
Paul B.

Well, miracles of miracle I actually made it to the range this morning. Left the house at 0615 and reached the range at 0645. Temp according the thermometer in my truck said 68*. Wind was forecast to be calm and was blowing about 6 to 12 MPH quartering the range from the southwest.

The rifle was the custom Mauser in 7x57 as mentioned earlier and the load was 45.5 gr. Re17, Remington brass, CCI 200 primer and the 150 gr. ABLR. I shot three shot groups. All powder charges hand weighed.

Load #1. two shots 15/16" No third shot. Dud primer failed to ignite the powder I've been getting quite a few misfired from those primers.

Load #2. 2 1/8" x 1" Best group of the test series.

Load #3. 2 3/8" x 1 3/8" Group was vertical in nature with the 2 3/8" the height.

Load #4. 2 1/16" x 1 3/8". Load #5 1 3/4" x 2 3/8". Not quite a perfect triangle.

This rifle is an enigma. Not only is accuracy eccentric, but loads will extract nice and easy one time that hard to open the action the next and this even with a known mild load. Here's where it gets even more weird. Case head expansion and pressure ring expanse are perfectly normal. Primer pocket after and average six loadings of hotter than normal loads from slightly over max to possibly close to absolute maximum for that particular rifle are still tight in that batch of brass. I've run those same loads in my M70 FWT and more reaching a very accurate load with the Nosler Partition and running 2900 FPS+. I also reached that 2900 FPS with the ABLR but with dismal or should I just say lousy accuracy. (with the ABLR)

I'm a bit on the stubborn side. I once bought a Ruger M77 RSI (The one with the Mannlicher style stock) on the cheap because it's original owner could not get it to shoot a group with anything he tried. It took me a little over two years to find a load that would give reasonably accuracy for hunting. I figured if I could get a consistent load that would do 1.5" at 100 yards then I'd call it good. Well it took a stiff charge of W760 and the Speer 165 gr. Hot Core. Velocity is only 2550 from the stubby 18.5" barrel but I've taken deer from 35 feet to 250 yards with it. Try any other 165 gr. bullet and forget about it. That's the only combo that will work in that rifle. My point being, I'll get that Mauser to shooting right. May not be tomorrow or next week but I'll figure it out hopefully before I turn toes up.
Paul B.

Howdy, All,

I started experimenting with the 7x57 Mauser (and from there the 7x57 Mauser Ackley Improved) about twelve years ago. My current 7x57 Mauser is a Model 70 Featherweight with a 22" barrel, a rifle which has received various tweaks and tinkerings over the years from a variety of gunsmiths. The rifle, still with its original stock, is glass- and pillar-bedded with a Timney trigger. With proper handloads, and if I do my job properly, this rifle is a sub-MOA shooter.

The 7x57 I had for several years before the Model 70 was built on a Mauser 98 action made in Czechoslovakia circa 1936 or so and fitted with a 24" Douglas barrel and Hogue stock. That rifle is now a 7x57 AI rifle with a new 24" Douglas barrel. It took several years (and two barrels, one in 280 Remington) before I managed to get the rifle to shoot straight. A friend of mine who is mechanically inclined deduced that the box-style magazine in the M98 is vunerable to lateral and frontal torsions if it is not fitted perfectly to a given stock. The torsions, which can be difficult to detect, were what caused the M98 to shoot everywhere except at a bullseye. Once we figured that out, we modified the Hogue stock and rebedded the action into the stock. With careful handload development, I have since shot some of the best groups I've ever produced with any high-powered centerfire rifle. It now routinely produces MOA or better groups with the right loads.

I also have two other 7x57 AI rifles, one built on a left-handed Remington 700 action with a 25" McGowen barrel and an HS-Precision stock, the other a Remington 700 right-handed action with a heavy (as in too heavy, which is my fault; it was my first custom rifle) Shilen 24" barrel, also in an HS-Precision stock. Both rifles are extremely accurate.

Loads that Work for My Model 70 Featherweight in 7x57 Mauser (all muzzle velocities are the average velocity of a five- or ten-shot group):

120 grain Barnes TTSX, 3.025" OAL, starting at 51g. of H-414 and chronographed 15' from the muzzle: 3041 FPS.

Slowly increased the load to 53g. of H-414 and 3144 FPS.

Note: I did incrementally increase the load to 54g of H-414 and 3218 FPS, but felt the pressures were becoming a concern, especially in the intense heat and sun of NE TX. H-414 powder is temperature sensitive. I discovered this with cartridges left out in the sun on a summer day.

120g. Nosler BT, 52g. RL 17, 3100 FPS.

120g. Nosler BT, 53.5g. H-4350, 3150 FPS.

120g. TTSX, 51.5g. RL17, 3100 FPS.

120g. TTSX, 54.5g. H-4350, 3165 FPS.

130g. Sierra Match King, 51g. H-414, 3030 FPS. Note: An accurate load.

139g. Hornady SST, 50.1g. H-4350, 2850 FPS.

139g. Hornady SST, 50.5g. H-4350, 2904 FPS. Note: This load, which is an MOA load, is as warm as I care to go. My field notes from eight years ago, which were usually derived the hard way, state: "Do not exceed 51g. of H-4350 with 139-140g. bullets."

140g. Nosler Partition, 50.2g., H-4350, 2845 FPS. This is an MOA or better load which appears to be safe in all temperature conditions. I did experiment with slightly increased powder loads--up to 51g. of H-4350 and 2920 FPS muzzle velocity--but observed primers beginning to look flat and the bolt developing slight resistance, so I backed the load down, incrementally, to 50.2g., which is accurate and has never given my rifle any problems.

Note: I have attempted load development with the both the 139g. Hornady SST and the 140g. Nosler Partition and RL 19 powder. I could not get satisfactory velocities (e.g., around 2850 FPS or higher) with either bullet without pouring so much powder in the case that it filled completely to the top of the neck. I compressed it, added more powder to the case, and compressed it again before finally seating a bullet. At this point, with up to 51.6g. of powder stuffed into the case, I developed a concern of future bad things at the shooting bench, so I discontinued using RL 19. (I am aware Nosler reloading manuals from the past decade list up to 51.5g of RL19 for 140g. Partitions or Accubonds, but at well over 100% compression rates. Why bother?) H-4350 is a fine powder for the 7x57 Mauser with appropriate bullet weights, as is H-414.

I have used all of the above loads (except the Sierra Match King) on wild hogs ranging from 75 lbs. to 300+ lbs, at distances of 25 yards to 250 yards or slightly farther. When I made a proper shot, I could not detect any difference in the stopping power of any of the loads. Wild hogs are incredibly tough. I have made numerous heart-lung shots at 25-50 yards with the TTSX and NBT loads, field-dressed the hogs and found nothing but mush where the heart-lungs used to be, yet the hogs always ran 30-50 yards anyway, which is impossible, but there it is. The only times I've seen instant kills on any of the hogs I've taken were with head shots, and I won't take a head shot unless I am 100% positive of my load, my rifle, the shot picture, the distance and myself on a given day. The vast majority of my shooting is done at the bench, with paper targets and often a chronograph at hand.

Regards,

Renaissance

Just my opinion but I think Re19 just might be a bit too slow for a 140 gr. bullet in a 7x57. However I have gotten some interesting results using Re17 in that cartridge. One load with Re17 and the 150 gr. Nosler Partition does 2847 FPS. Primers look reasonable that the cases have been loaded 5 or 6 times and primer pockets are still reasonably tight. With that said though, I've dropped the load back enough for a velocity of 2710 FPS with only a slight loss in accuracy. Rifle is a Winchester M70 Featherweight. That top load also shot well in a Ruger #A in 7x57 but even the 2710 FPS load locks up the bolt on a custom Mauser I have. I have absolutely no idea why but it shows high pressures long before the other two rifles. Damn thing is driving me sane.
Right now I'm trying to get the Nosler ABLR 150 gr. bullet to give some modicum of accuracy but it hasn't worked in any of my 7x57s and not in my .280 Remington as well. Probably be a few days before I can get to the range. We've had a few heavy rain showers the past few days and the range is usually a mud hole.
I did a bit of work with the 160 gr. Speer Hot Core but it and Re17 apparently don't agree with each other. I'll probably run a series with H4350 when I get done with the ABLRs.
Paul B.

Tighter, shorter throat?

PJGunner, your comment about RL19 and 140g bullets is not something that had occurred to me before, but I think you are right on in your assessment that RL19 is too slow for optimal performance with 140g. bullets. I have never gotten desired velocities with RL19 and 140g bullets in any 7x57 Mauser or 7x57AI I've owned.

Note: I too have had difficulties obtaining MOA or better groups with Accubonds, in every caliber and every rifle I've fired them in. I've done so only with difficulty. Oddly, I've routinely shot far better groups with Partitions and Ballistic Tips, so that's what I use in Nosler bullets these days.

Regards,

Renaissance

No, it has the standard long throat common to the 7x57. One thing I have notices is it has the tightest chamber of any rifle I own. You know how when you look at a fired case how there is usually a slight bulge to one side near the hear of the case? Well the bulge from ammo shot in that rifle literally has no bulge. It's there but most of the time it takes a micrometer to find it. Only the really hot load show it enough to be easily visible.
Paul B.

I've found that in my rifle H4350 is as good as it gets. RL19 was too slow, and even with 4831sc and 50.6gn in the case behind a 160gn Protected Point Woodleigh bullet, it didn't shoot as well as H4350 did. at the moment I'm pretty happy with Norma Brass, CCI LR primers, 50gn H4350 and a 139gn Hornady SST doing 2,800 at the muzzle. 154gn Hornady Interlocks aren't too shabby either. It was mentioned somewhere here that you should try for a reasonable muzzle velocity, and work your load development around that, not a bad idea as long as accuracy is not compromised.

Paul I seem to recall that the Mauser custom rifle has a shorter throat than your other sevens, if that's correct, your problem may be due to the short throat not in agreement with those heavier bullets. How does it handle the 100grainers?

My Mauser custom has the standard long throat common to military barrels as this was one of my specifications when I had the rifle build done. Twist is also the standard as originally used in the 7x57 rifles. Lightest bullets I used in that rifle are the Barnes 140 gr. TSX which it definitely does not like. Federal 175 gr. factory shoot reasonably well and Winchester 145 gr. factory ammo are decently accurate but I'm looking for the potential the cartridge has, not the underloaded factory levels. I get great velocity and accuracy from a Ruger #1A with 22"barrel and even better velocity from a Winchester M70 XTR Featherweight with 22" barrel. The Mauser has a 23" barrel.
Paul B.

RL19 has worked very well for me in the 7X57.

The best powders for 3 of the 7x57s that I have had was always 4320 ,4895 , or 4064. I did not try to push them to max and tihs powder was always with 139, 140, 150, and 154 grain

bullets.

I have had good results with Woodleigh 160 grain pp bullets ahead of IMR 4451 or H4350 in my 2014 M70 featherweight. Cases and primers are both by Remington. I will not state what the powder charges were (as they are "over book"), but I followed MD's recommendations as published here on the "Fire and in his magazine articles. They work! A chronograph is a great help in load development. No over pressure signs noted.

My seven also likes the 160gn Woodleighs but not using H4831sc. I've found that H4350 works best on all bullet weights from 140 to 160 and that's about the only weights I shoot now. Although I did give the Hornady Interlock 154gn a run, and they did Ok. I only shoot 3 round groups in my hunting rifles, because A) the barrel gets too hot, and B) if you haven't killed it in 3 shots maybe hunting is not for you.

Powder temperature sensitivity better known as ( hunters excuse for missing) LOL