question about trimming Brass

[atr]

I bought some used 257 Roberts brass from a member here and found that it was all trimmed very short
the published design length is 2.233"
however this brass was incorrectly trimmed to 1.9"

any adverse ramifications if I use this brass for full power loads??...I can think of higher pressures but I doubt if the higher pressure would be significant.

your thoughts are appreciated

thanks
atr

[TNsailorman]

That's pretty short but I can't think of any reason for safety concerns. Unless the shoulder is set back too far. Maybe accuracy concerns---maybe not. They will grow with a few firings and will eventually grown back to proper dimensions if all other dimensions are correct. I once bought a bunch of 30-06 brass that had been trimmed way short. I reformed it and turned it into 8x57. That is not what I wanted the brass for but it worked out for me--after a lot of work. The guy I bought the brass from told me he would replace the brass but never did and I could not contact or get him to answer again after that promise. I would contact that member and ask him for replacement or refund if I was in your shoes. Unless you have another cartridge that you can convert the brass and use--which I doubt. james

[losttrail]

I'm thinking differently.

Looking at a dimensioned schematic of a .257 Roberts case, 2.233" - 1.9" = .333" or over 5/16"! 1.911" is the center of the shoulder-to-neck radius so the neck would be completely gone if these numbers are correct.

Yes, cases will grow some when fired, but I doubt .333". That's 3/10 of an inch.

Am I misreading or misunderstanding something?

[atr]

thanks guys...
I am going to use the brass with loads at the low end of the charge scale. The neck was not set back; I snapped a couple of primer caps just to make sure...
and yes 0.333 is 21/64...
atr

[losttrail]

106829

I guess I'm having a hard time understanding how cases being trimmed to 1.9" would not be a problem based on this.

[magic mike]

I'm with you on this one losttrail. There is no way those cases will work if they've been cut (way past trimmed) to 1.900". Something is not right here.

[country gent]

Im wondering if its not a 250 Savage as its trim to length is 1.912. A .257 roberts trimmed to 1.900 would have no shoulder left. ATR what rifle is this for? My numbers are coming from Lymans Cast Bullet Handbook 4th edition. 250 savage 257 Roberts
CAse length 1.912 Case trim to length 2.233
OAL 2.515 oal 2.775

[boho]

Are you sure they haven't been sized in Ackley Improved dies? What's the shoulder angle?

[str8wal]

If you cut a 257 Bob to 1.9" there will be no neck left. Impossible to use.

[seaboltm]

If you cut a 257 Bob to 1.9" there will be no neck left. Impossible to use.

+1

That brass has been converted to something else. 250 Savage or some wildcat. Who knows. The bob has a relatively short neck. cut that much off and you are into the shoulder. It would almost look like a straight walled case.

[atr]

My apologies guy....the number i should have typed is 2.19"....ahhhhhh !!!!

[FLHTC]

it will save you from trimming for a while. i actually trim shorter than .004 from spec.

[TNsailorman]

The new length figure changes things dramatically. 2.19 instead of 1.91 means that you have a rifle with case that is introducing "freebore" to the equation and that is not necessarily a bad thing. Theoretically, you should be able to run the velocity a little higher with those cases because of this. Its like the use of a 5.56 case in relationship to a .223 Remington. The 5.56 chambers in AR15/16's have a little freebore and thus can be loaded to higher chamber pressure--depending on the case used and rifle. In this instance, the case itself is introducing the freebore instead of the chamber. I hope I stated this correctly, its keeps going round and round in the old noodle. james