gentlemen -

as most of you know, i've got a cz m550 american in 7x57. i am going to begin some serious load development for it and invite any and all to check out the running thread as it progresses over the year. the culmination, of course, will be on game (deer and possibly antelope) this fall.

here is the link:

http://www.baitshopboyz.com/forum/forum_posts.asp?TID=12088&PN=1

this development is starting entirely from scratch. i've made some preliminary choices regarding components, but that's about it. feel free to offer any comments, suggestions, opinions or advice.

thanks!

ron

I'll be watching for your results. For your uses, there is no need for any bullet heavier than 140 grains, except to reduce meat damage.

I have had excellent results in the 7X57mm with WW760, H414 (almost, but not quite the same), and IMR 4350 with bullets up to 150 grains. Over 150 grains, I use Norma MRP or Alliant RE 22.

I have a load (for Rugers-a No. 1A and a Model 77 with long throats) that gives 2820 FPS with 160-grain bullets, one that gives 3000 with the 140-grain Sierra and Nosler Partition bullets, and one that gives slightly over 2700 with 175 grain Nosler Partition bullets. All these are MOA loads. And I'm getting at least 10 loadings out of a batch of brass with these loads!

In addition, I am presently working on a load using Nosler BT and Remington Corelokt 150-grain bullets for a Mannlicher-Schoenauer carbine with 20" barrel. My goal is 2800 FPS with at least 1.25 MOA accuracy. So far, I have been using IMR 4350 with these bullets. Started at 50 grains. So far, accuracy has been excellent!

I currently have the two Rugers, a Mannlicher-Schoenauer, and an FN Venezuelan M1924 Mauser in 7X57mm. All are quite accurate with the right loads! I doubt that there's a better cartridge in this caliber niche!

Good luck!

thanks for the comments, E.D. lots of good information there, and i'll be adding it to my notes, if you don't mind.

i'm basing my (preliminary) choice of 150-grain SGKs on the reports i've had that they are good, accurate, long-range bullets but tend to over-expand a bit. i figure the weight and boat tail will help accuracy downrange and also contribute to good, controlled expansion versus a lighter bullet. this is all hypothesis, but i figure that for my chosen bullet, a slightly-heavier-for-caliber bullet might be in order. the heavier bullet also means good SD (and, as you mentioned, less meat damage), and that never hurts, either.

regarding your attempts with the NBTs and the corelokts, you might contact a member there named tj3006. if i recall correctly, he was able to get 2800 fps with 160-grain bullets. i honestly have no idea what the load was, but for some reason VARGET rings a bell. if he can do it with 160s, you should be able to do it with 150s, assuming safe pressures. a search should be able to turn it up, or send him a PM. his rifle is a cz with the mannlicher stock.

If you don't already have it, I'd suggest the Load Book (Midway has them) for 7x57 which lists just about everyway you could possibly put 7x57 brass and 7mm bullets together safely.

Speer's data seems to run a bit hotter than the other data listed, I'd guess they could be called the +P data...

Good luck.

Taz...

For problem 7 x 57s with accuracy problems.. 40 grains of IMR 3031 has proven to solve a lot of them... don't ask me why, it just works..

It is not a real trendy powder in todays world, because it is not on the slow burning powder lists which seem to be in vogue.. however 3031 has been around for a long time.. for a reason...

With bullets from 139 grains to 175 grains, a charge of 40 grains will give you some very accurate loads.. ( especially recommend loading the cartridges magazine length, about 80mm COAL)...

with the 175s, MV is 2650 in my Ruger 7 x 57s (I have Two)...and with the 140s the MV is about 2750....so the point of impact is pretty close, with the extremes of 140s to 175s...in bullet weight...

I got started on this route in an older Hornady manual and the Lyman 47th Manual as reference..

click here for an update

quote:

Originally posted by El Deguello:
For your uses, there is no need for any bullet heavier than 140 grains, except to reduce meat damage.

I have had excellent results in the 7X57mm with WW760, H414 Good luck!

I second El Deguello's comments.....

H-4350 is also a good choice for the 7X57

For deer and Pronghorns I'd use Hornady interlocks (139 Grain) and you should be able to get at least 2,700'/sec and if you work up carefully 2,800'/sec...... as it is close on the heels of the .270 winchester when loaded in a modern bolt rifle.

The opinion that the 140 gr. bullets are as heavy as you need to go in the 7 X57 is not shared here. Bullets from 150 to 175 gr. adequately put the 7X57 in a catagory of animals larger than mule deer. IMHO a 175gr. 7mm bullet has a definite edge over a 140gr. when talking ,let's say, Elk.

I'm not sure what grain bullet Bell used on elephants but I'd be surprised if it were a 140. Back to de roger

Unless your barrel is significantly different from standard 7X57 design it is highly likely that it will perform at it's best with long heavy bullets.

If you want some frustration try the 140 grain Hornady boat tail.

quote:

Originally posted by ireload2:
Unless your barrel is significantly different from standard 7X57 design it is highly likely that it will perform at it's best with long heavy bullets.

If you want some frustration try the 140 grain Hornady boat tail.

roger

I have loaded for 27X57s.
My old CZ 550 full stock liked H-414 for lighter bullets.
But for the 160 grain slugs it was real fond of RL-19.
My currant #1A shoots extreemly well with IMR-4350. I am getting great groups and 2875, with 140 grain balistic tips.
...tj3006

"38 grns – One shot missed the target, leaving a wide four-shot group measuring 3.05 inches (net - 2.775 inches). The “center†of the group was approximately ¾ inch above and 1¼ inches to the right of the bull’s eye. One case ended up with a split neck for unknown reasons."

I'd bet that the round that missed the target was from the case with the split neck. Seems to me that maybe your brass needs to have the necks annealed.
Paul B.

Some good advice given here - but I would add one caveat: Don't use the lighter bullets to shoot anything you are going to eat! I think the worst shot up deer I have ever seen in some fifty years of hunting was shot with a 7X57 with 139gr Norma Tri-Clad bullets. Wonderful for varmits but not worth a damn for shooting white tails!
My own experience has been best with the Hornady bullets, the 154 gr RN and the 162 gr BT being my all time favorites. I load them over H4350 and in a word: They work! I find the RN to be ideal for most shooting if I stay in the woods, out in the open the 162 BT seems to be the better long range - no surprise there.
So, we are on the verge of the season so we will be looking forward to some reports from you.
And remember, the 7X57 was developed with the 173 gr bullet so they had to know something!