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View Full Version : Which cast boolit varminter... 257R or 6mm?



Marlin Junky
05-03-2012, 02:35 PM
I'm wondering if anyone has done any serious accuracy load development with these two and what were the results.

Oh yeah, I'd also like to know if the .257 has any advantage over the 6mm in terms of performance on "game"; i.e., does the 12% increase in cross sectional area mean anything in terms of real world performance on critters less than 100 pounds, or is it mute when twist, velocity, etc. are part if the equation? Obviously, dependable, repeatable accuracy is paramount.

Thanks,
MJ

miestro_jerry
05-03-2012, 05:18 PM
I use a 243 and took it over my 257 Roberts. I took a deer over in W.V a while ago at 175 yards with a CB in my Rem 700 BDL.

Jerry

x101airborne
05-03-2012, 06:37 PM
For varmints, it's tomato, toma'to. For an opinion, I like the boolit / bullet selection for the 243 / 6mm family more than the 257's. Eh, it's what you like ultimately.

Bob Krack
05-03-2012, 07:31 PM
I'm not a .257 fan but given the choice, I would choose the .257. Just like most girls say "the bigger the better". 'course my experience is with a .257 Wheatherby Mag!

Embarrassed face and all.


Bob

runfiverun
05-03-2012, 08:17 PM
if you can find an older 6mm rem it has the slower twist rate, that will help things along.
some of the early 260's had a slower twist too.
otherwise they both have a 10 twist bbl and about 2-3 factory mold choices.

excess650
05-03-2012, 08:32 PM
I was going to chime in that the 6mm Rem and 257 Roberts share the same 7x57mm case. The 244 Rem was the early version with 1-12" twist while the 6mm was 1-9". I would have guessed the 257 Roberts to have a 1-12" twist (vs 25-06 with a 1-10"). Regardless I would expect it easier to get good results with the 257 Roberts with cast even if both are 1-10" twist. Most definitely a 1-12" twist would be preferable (over a quicker twist) for cast from either bore size.

The 100gr Saeco 25cal has tempted me, but I have enough 30s to feed. My 25-06 and 7mm RemMag will just have to wait....

303Guy
05-03-2012, 11:15 PM
I would think that because cast is better with heavier and lower pressure, the 257 might be better but with equal twists, the smaller bore might win on spin. But for the same weight boolit the 257 would have a lower pressure for the same velocity. Then again, the 243 has a smaller case which might be better for cast - then again, maybe not. But if'n it were between the 257R and 6mm Remington, I'd take the 257. Easier to cast bigger boolits if nothing else plus it has a heavier boolit choice for game.

quilbilly
05-03-2012, 11:23 PM
The nice long neck on the 6mm Rem case really helps to make it accurate. I have a 250/3000 and a mold but as of yet have not done an accuracy test but if I am having a good day, my 6mm Rem already gives me groups under 3/4" at 100 with the Lyman 90 gr boolit. The operative phrase there is "if I am having a good day" of course.

Marlin Junky
05-04-2012, 07:08 PM
Nobody mentioned anything about typical throat config's for .244/6mm/.257R chambers.

MJ

Marlin Junky
05-04-2012, 07:12 PM
...6mm Rem already gives me groups under 3/4" at 100 with the Lyman 90 gr boolit. The operative phrase there is "if I am having a good day" of course.

Any experience varminting with that boolit (I assume it's a round nose Loverin)?

MJ

quilbilly
05-08-2012, 12:45 AM
It is a round nose boolit. I haven't taken it in the field much yet but did get one coyote at about 150 yards and he was DRT.

reloader28
05-08-2012, 09:05 AM
I know the 95gr RCBS SP shoots like a dream out of my 243's.
1/16" hollow point 3/8" deep is very impressive on varmint's. Very accurate too. 3/4" @ 100. Good enough for me.

I need to get a different boolit for my 257 because of the wrong barrel twist (custom built varminter). I told the wife I needed a different 257 to match the mold I have, but she said NO. Kinda narrow minded of her I thought.
So I guess I'm stuck getting a different mold instead.

Marlin Junky
05-08-2012, 03:26 PM
I know the 95gr RCBS SP shoots like a dream out of my 243's.
1/16" hollow point 3/8" deep is very impressive on varmint's. Very accurate too. 3/4" @ 100. Good enough for me.

Here as well. What velocity are we talking about?


I need to get a different boolit for my 257 because of the wrong barrel twist (custom built varminter). I told the wife I needed a different 257 to match the mold I have, but she said NO. Kinda narrow minded of her I thought.
So I guess I'm stuck getting a different mold instead.

Or your own checking account. :bigsmyl2:

MJ

reloader28
05-09-2012, 09:05 AM
That is only around 1750fps. I aint took the time to try faster loads yet.
I shot a skunk once at about 80 yards and it pretty much blew out the whole exit side. Big pile of goo. I'll have to look and see if I still have the picture.:bigsmyl2: