7x57 and RCBS 7 mm 168 sp

[Wolfer]

I am in the process of acquiring a mold for my 7x57. I'll probably start with 15 gr of 2400 and work up. I have no experience in anything cast below 30 cal.
Does anybody have any experience with this cartridge and boolit? Suggestions on powder? Things to watch out for?

[stubshaft]

Nothing unusual about this cartridge just cast and load as usual. I preferred the 145 RCBS ahead of 14.0 Unique. Just use basic cast loading techniques, don't forget the "M" die.

[405]

Have a bunch of experience with cast 7x57 in only one rifle. But there are many on this forum who will likely pipe up.

My 7x57 (95 Chilean original form) likes the Lyman 287641 bore rider sized to .285. One of the few milsurps of that age I've played with that required nearly no load "tuning". I load the 160 gr 12 BHN GC 287641 over 18 gr 5744 and use dacron filler. MV ~1600 with very low SD. Very accurate. I didn't need to try any other bullet nor any other powder or load once I tried this one. Don't know about the RCBS bullet as I have no experience with it.

[45-70marlin]

Wolfer, I use this mold for my 7mm-08 with 15 gr. of Unique and will do around a inch at 100yds. I also use IMR 4195 25.0gr. that even shoots better than unique. You will like this bullet for your 7x57.

[Wolfer]

I have unique on hand. Do you know what your velocity is?

[lotech]

While I no longer have the RCBS mould or a 7x57 rifle, I have some notes regarding loads I used in my bolt-action Ruger 15 or 20 years ago:
Linotype, sized .285" or .286", CCI-200 primers, Rem. brass, OAL= 3.10",
two best loads ( most accurate) - 29 grains Accurate Arms #2230 = 1872 fps
23 grains Reloder 7 = 1768 fps

[atr]

IMR 4895 is also a very good powder for cast loading in the 7x57.

[405]

Wolfer,
Since the devil's in the details with how well these thing work you might slug your bore to see what the best cast size might be.... especially with these bore riders like the Lyman I shoot and the RCBS you are talking about. BTW they appear to be very similar in design.

The nose of a bore rider bullet, to be most accurate, has to be a bore rider. The nose really needs to have good contact with the lands when the round is chambered. If the nose is a sloppy fit, there is no chance for good accuracy.

Example: My 7x57 has .276 bore and .285 groove. The Lyman I cast has .277 nose and is sized to .285.

Once you get your bore specs it'd be good to know the nose specs and as-cast drive band diameter of the RCBS bullet.

[Wolfer]

I agree 405. Once I get the mold I can see what it throws, slug my barrel, and decide if it will work or if it needs lapped. Worst or maybe best scenario I can always paper patch. I haven't had any luck P.P ing with any of my existing rifles because my molds all fit my barrels near perfect.
It seems like I'm trying to fix a nonexistent problem

[45-70marlin]

hey Wolfer,
In my Lyman book 7x57 160gr. with 14.5gr. Unique it goes about 1610 fps. I think the RCBS bullet would be close to that. you will a lot of fun playing with the diffrent type powders and such. One thing I will say is make sure you clean off the lube off the base of the gas check as it will affect accuracy.

[Larry Gibson]

I've the older origianl RCBS 28-168-FN and it is excellent in my M95 over 4895 with a dacron filler. I size at .287 which is "as cast" and find the best accuracy in the 1800 - 1900 fps range.

Larry Gibson

[x101airborne]

Larry, you really gotta quit showing pics of those BEAUTIFUL classics. Every time I see your posts I have the desire to go build another custom mauser. I love Manlichers!