257 Roberts problem

[georgewxxx]

This might be a bit off topic here for lead shooters, but it does include shooting cast so here goes.

Two weeks ago the phone rang, and it's the guy that owns the land I usually deer hunt on. His nephew is back here in South Dakota for a visit. He brought along his girlfriends custom Mauser 257 Roberts and they want me to help mount a new Bushnell 3X9 on it. No problem, bing it over I say. Well when he gets here it a beautiful 40 to 50's vintage custom Mauser with the most beautiful Birdseye maple stock I've ever seen. The kid says they can't keep the scope on target and it must be buggered up inside. The mounts and rings are old Weaver, but the rings are of the old solid type where you need to disassemble the scope to put on and take it off. So I send him into town to the gunsmith to get the proper hight rings and mounts.

Two days later they come back with $95 worth of Buhler rings and mounts partially fastened on. So we get the scope lined up and all cranked down tight and proceed to my pistol backstop to see how well we got it eyeballed straight. All he had along was a single box of high test Hornady 117gr 257plus P condom stuff. I grab a 50 rd box of my deer hunting Cast 257325HP that I shot my deer with last year just to get him close to where he needs to be. After we get him on target we switched to his plus P stuff. Every one of his key holed or slightly so. I've never seen factory ammo do that. His gun had no markings on of any kind. Not even a caliber designation.

Well he wasn't going to hunt with my cast stuff and that Hornady ammo was out, so We went down to the shop and assembled some condom 120gr Winchester stuff that I had a part box of. We loaded three and went back out and the gun shoots perfect, right on target. I had him shoot a few more of his factory stuff and it's back to the same tipping thing.

At first I thought we had a barrel with the wrong twist for 117gr boolits, but the 120gr shot fine as did my slow 2200fps cast ammo. Too slow a twist? I know hind sight is best, but I never did look down the bore. Not that it would tell me much anyway. Anybody know what happens to over stabilized boolits? Do they tip like under stabilized too?


I git a call yesterday saying Brian had sent a couple hundred rounds of fired brass for me to reload. I used up all the condom stuff I had so I guess I need to replace what we shot up or reloaded for him, but What weight and how snorty do I load for gun that's down in Missouri and more than likely I'll never see it again? ...Geo

[13Echo]

I suspect the 117 gr were boattails and actually slightly longer than your 120 gr bullets (flatbase I suspect) which put them just a bit too long to stabilize with the rifles twist. Since it is a custom it may have a 1:14 twist like the 250-3000 which is optimized for the shorter, lighter bullets. If so even your 120gr bullets may not be stable at longer ranges. I strongly suspect the rifle will shoot much better with lighter, 100 to 110gr bullets.

Jerry Liles

[runfiverun]

i have heard good stuff about the 95 gr partition.
i wouldn't want to do the mail me 5 more of those i think they were about what i wnt
deal though.

you have my sympathy.

[willwork4ww]

I've had problems getting the Bob to stabilize anything over 115 gr, lots of keyholes. I would suspect understabilization, over doesn't tend to harm anything acccuracy wise. At least not enough that u could tell in a sporting rifle. I too, would be extremely reluctant to ship off a bunch of ammo for a rifle I couldn't experiment with. My best advice to him would be, "take up handloading yourself and see what you can determine, or buy factory 100gr ammo and run with it".

[Lloyd Smale]

i would guess its twisted 1-14 back in the day it was common for 250s and 257s as they were primarily considered varmit rounds. Ive got a little light weight carbine win. in 250 that will drive nails with 87s does fair with 100s and shotgun patterns 117s. YOu might have a smidge more luck in a good strong 257 if you kick the velocity up a tad. But my first suggestion would be to try 100s. Ive had great luck on deer with sierra 100 flat based spitzers and speer 100 grain bt spitzers in the 25s.

[Bret4207]

Excellent 1 shot kills with the Nosler 100 gr Partition in my son's 250 Savage. I imagine the 257 would be more of the same.

[bobk]

Bret,
Roger that. I made the best whitetail kill I will ever make with my .257 a few years ago, with the 100 Partition. That's the gun I intend to give to my granddaughter, if she's interested. She hasn't expressed much interest yet, but she's not quite two years old.

Bob K

[georgewxxx]

I think Jerry(13Echo) had the right idea with the longer boat tail boolit being the problem. There must be a fine line between stable & unstable in that particular rifle. I've got two 257 Roberts and have shot slow to fast cast in both and have never tipped any. Those old 1960 vintage 120gr. Winchesters seems long when I compared them to my 119 gr 257325. Actually I have a notion to load him up with 50 rds of my cast hunting load and tell him to try them and see if he's satisfied. They shot extremely well at my range. If nothing else, he'd have loads of fun banging away real cheap. I haven't a clue what Missouri deer country looks like, but here in eastern South Dakota they do the job....Geo

[Parson]

257 Roberts is my personal favorite and have built more custom 257's than any other caliber. When I first started gunsmithing many many years ago I was warned by those who had been around a while that in spite of barrels being labeled 1 in 10 few were, some 1 in 9 1/2 and some in 1 in 10 1/2 etc. The 25 cal. 120's which by the book should be fine in a 1 in 10 were so border line that the standard factory round became the 117 because there were just too many good barrels that would not stabalize the 120's. It is almost a non existant problem with our barrels today. The advice above about stabalization is about 99.9% correct 90% of the time with the 25 cal. at in and around 120 gr. and a claimed 1 in 10 twist

[Ed Barrett]

Where in Missouri is he located?

[georgewxxx]

Ed, From what I hear, it's somewhere around Joplin...Geo

[twotrees]

BUT it has a Ken Obermyer barrel on it.

It is the ONLY gun I have that I have loads for 75 gr (Max in Nosler book) with IMR 4064. At 3300+ FPS.

100 gr loads for Hornady and Nosler partition with IMR 4831 (3100 fps.

And 117 Hornady bullets at 2800 fps (IMR 4831).

The only thing that changes is vertical zero. 75's are 2" up at 100 ( Varmint)
100 Both are 1" up at 100. Deer.

the 117's are on zero at 100 (hogs).

Of all the guns Ive owned, all have had some horz. spread when changing bullets or powder. This one is a jewel as all I need to change the game I'm hunting , is pick up the right bullet box.

The guys are right, sounds like you need to measure the twist of that Barrel, and load the bullets it likes at the right Vels.

BTW: Ken throated this one for a 3" loaded length,and thats what I load to. So I will NOT give powder charges , as they might be too hot for a standard length 257 Bob.

Good Shooting,

TwoTrees

[NoDakJak]

Over the years I have owned five custom Mauser 257 Roberts rifles plus one in a 77 Ruger. All had 1 in 10 twist Douglas barrels and handled the 100 grain flat base slugs very well. A couple didn't want to stabilize 120 grain flat base slugs and none would handle th 120 graint boat tails. Ah well! Nothing that I shot ever seemed to know the difference. I have an almost new reamer and plan on building another series of custom Mausers for my grandsons and maybe my grand daughter also. Save the 120 grain boat tails for the 25-06. And yes, I have an almost new reamer for that alo. Neil

[carpetman]

NoDakJak--Read your post that you were Navy/Air Force. Me too. Naval Reserve time and 24 1/2 active AF. Read you like CZ's---me too but dont have one. Read you have grandkids--me too--one grandson is big time hunter. Read you like .257 Roberts--me too never had one. Read you like .223---me too--and have one. Read you like the hornet--me too--never had one. Read you like .204---dont have one but it perks my interest. Now I read save bullets for 25-06---WHAT????? What will a 25-06 do that a .270 wont do better and a .257 Roberts will do with more class? oh and BTW for title of thread and to be on subject I'm uhh ummm 21. OOOpppsss-wrong thread but had it been the other one I'd been on subject.

[georgewxxx]

Guys you gotta understand that there won't be any money exchanged in this reloading project, so I'm not about to shell out for some fancy high end boolits. If you read what I said at the beginning, it's a nephew of the gent that owns the land where I've been privileged to hunt. So I'm trying to get by as cheap as possible and still get them ammo that will do the job. I see Graf has Hornady 117 round nose,and they'll work out just fine I;m sure. Graf has My C&R license so I get a bit of a cut there too. When I first saw the price on his box of his plus P 257 Hornady's I about choked. I Haven't paid for factory fodder since 1964. You all know how all components have gone up in just the last 6 months. UF-DA....Geo

[DLCTEX]

"You all know how all components have gone up in just the last 6 months. UF-DA....Geo"
Have you priced 257 Weatherby lately? STICKER SHOCK!!!! DALE

[NoDakJak]

Carpetman-I can't really say what the 270 will do better than the 25-06. Every time that i build one or the other someone comes along tht seems to need it worse than I do. Ah well! I know damned well that the Roberts will certainly take either deer or antelope at 400 yards. Don need no steenkin short magnums. Iffen ya kaint do it with a Roberts then get a bigger gun. 25-06 or 270! For those that swoon at the thought of sheer power i would even consider the 30-06. Neil the Airdale

[Bret4207]

George- That 117 RN should work fine. So will the standard 100 gr SP type designs as long as the game isn't too heavy. I have Junior use the Partitions more froma lack of trust of his judgement than a lack of faith in the 250.

[georgewxxx]

Bret,
A few years ago I loaded uo the tail end of some 117 Herters round nose I had stashed for my nephew who had just started his deer hunting carrer. His first kills where small does. Then one year he took a nice sized deer off their back borch at close to 200yds.

I did did a quick 257 cast article for Beagle that's in Castpics if any of you care to see my two rifles and load data. It's in the Members Articles section. In it there are pictures of the boolis moulds I had at the time. My favorite is the hokey looking 257306. ...Geo