Do I need to give up on this mold?

[hornady]

I bought a 7x57 Mauser too shoot cast bullets in, my first mistake was I bought the 135Gr, GC mold. From reading old post I should have used the160Gr, I have tried 3 different loads of Red dot with a max of 13 Grains with these cast bullets. Not all but half the bullets key hole. I stopped into the gun shop yesterday and bought a box of Hornady 154 Grain jacketed Bullets, I loaded 10 with 35.0 Grains of Varget for a test load. At 50 yards I had 10 perfect holes, with a 2-inch group off hand. I cast and load for 3- 30 cal, rifles and several handguns. This is a new one on me. Should I sell the 135gr, mold and retry with the heavier cast bullet.

[swheeler]

I bought a 7x57 Mauser too shoot cast bullets in, my first mistake was I bought the 135Gr, GC mold. From reading old post I should have used the160Gr, I have tried 3 different loads of Red dot with a max of 13 Grains with these cast bullets. Not all but half the bullets key hole. I stopped into the gun shop yesterday and bought a box of Hornady 154 Grain jacketed Bullets, I loaded 10 with 35.0 Grains of Varget for a test load. At 50 yards I had 10 perfect holes, with a 2-inch group off hand. I cast and load for 3- 30 cal, rifles and several handguns. This is a new one on me. Should I sell the 135gr, mold and retry with the heavier cast bullet.

Sounds like your bullets are undersize, what does the barrel slug and what size are your bullets casting/being sized to.

[Wally]

I shoot cast in my Rem 700 7mm Rem Mag...using 18.0 grains of Unique. I have a Lee 130 Cast GC and a RCBS 168 SP-GC bullet molds. I size to .285" and found that the heavier bullet is more accurate. Howver I plan on experimenting a bit more to see if I can change that. It is best to seat the bullet out long so that it engages the Leade when chambering...typically I only shoot my 700 as a single shot when using cast bullets. Also, I raise, then slowly lower the barrel so that the powder is in the same position when firing. I have used Hornady GCs and home made aluminum GC's...I have found no apprecaible difference between them.

[runfiverun]

i have both the rcbs 145 and the 168 gr molds.
i can't get the 168 to chamber in most of my x57 rifles.
you are either too small in diameter or you have a tight spot somewhere in the bbl.

[atr]

I shoot a 7x57 DWM made...and the tolerances are tight and bore is perfect....so I have found that the 135 gr does work well for me...
however I did have an old turkish 7x57 which was very rough and the 135 keyholed on me all the time no matter what dia. or charge I tried.

my suggestion would be to try your 135 as cast (largest dia. possible)....you may have to set the gas checks by hand and also pan lub

good luck

[Larry Gibson]

Hornady

What rifle?

Have you slugged the throat or bore?

What are you sizing the cast at?

What alloy?

GCs used?

Larry Gibson

[hornady]

What rifle? Chilean Mauser

Have you slugged the throat or bore? Bore .284

What are you sizing the cast at? .285 I mic, the bullets and they are .285

What alloy? It’s a little harder than Lyman #2. I use this same mix in my 30 cal bullets with no trouble.

GCs used? Hornady I use a Lyman 4500 Lube/Sizer. I am using BAC special blend lube

[1Shirt]

My 77 Ruger 7x57 shoots just about any cast or jacketed blt you stuff in it. Prefers, accuracy wise the heavier weights in either but is more than acceptable with less than 140 grainers. Mine shoots .285. Suggest that in all probability your milsurp requires a larger dia, of .286 or maybe even larger.
1Shirt!

[MtGun44]

I suggest .002 to .003 over groove diameter in rifles. For .284 groove, use .286 or .287.

Bill

[geargnasher]

Got one of those 7x57s with the humongous chamber neck? What's your loaded case neck/chamber neck clearance?

Gear

[hornady]

My friend still has the mold but I did a little experimenting with some of the bullets I had cast on hand. I played around with seating depth. I eased the depth out to 2.900. With 12.0 Grains of Red dot. One grease ring is out of the case. The key holing stopped, and groups tightened up, still nothing to brag about.
If I get the mold back I may cast some more of these bullets, I am thinking drop the GC and use a buffer, I have been reading a little on buffer agents. I have read the top three are cream of wheat, steel shot buffer, or hard wood sawdust. From what I read the Buffer should be slightly compressed.
Moving the bullet out of the case, too 2.900 seemed to be the COL I need, at 2.950 I started loosing accuracy. Now I kind of hope the mold doesn’t work for him. I think I may get this too work with different powder and buffer with the long COL.

[Bret4207]

Don't even bother trying it w/o the GC, it's not going to help at all.

First question- have you de-fouled your barrel? If it's still full of jacket fouling you are in for a rough road.

2nd- Seat the boolit, if possible, so it is well out into the throat and toughing the lands if you can. A larger boolit will likely help too. Your groove size may be ,284 but I bet your throat is much larger and a yard long. That may well be your problem area.

[Lance Boyle]

I would do all those suggestions but in order;

1. Decopper the bore - I would suggest using a good solvent like Wipe Out to get the old copper out. The stuff works and is safe for your bore unlike some of the older cop out solvents. Once you get it well decoppered you can go back to basic hoppes to save money or be really cheap and make your own Ed's Red solvent.

2. Slug your throat and your bore again, when you slug the bore take notice if you have any tight spots, I'd run a slug each way to be sure if you suspect this is the problem.

3. Assuming you have fat enough castings, I would definitely go 2/3 thousanths over bore. I'm of the notion this is a pretty easy shortcut for cutting out half the problems in cast boolit rifle reloading. Assuming your case neck has the room to expand.

That said, i'm a learning newb and SLUG myself (SLUG- Slow Learner Under Guidance).

[Bret4207]

Tom, GROOVE! 2/3 thous over GROOVE size, not bore, gotta watch the terminology ya dumb ol jarhead! :kidding: