Cases arrived a little short

spclPatrolGroup · April 4, 2011, 09:39 AM

I purchased some new Winchester brass in .270, minimum case length is .530 but a couple that came were .529 and one or two were .528, should I throw these out, or are they ok to load?

mapsjanhere · April 4, 2011, 09:43 AM

Ok to load, and after the first resizing they'll be the right length.

**Mal H** · April 4, 2011, 09:56 AM

Wow! You're right, those were really short! All of my .270 Win cases are easily 2 inches longer than that.

2.530" is a "trim-to" length, not necessarily a minimum length. New cases a few thousandths less are not unusual, but you don't want them a lot shorter than that or the bullet purchase length starts getting to be a factor.

spclPatrolGroup · April 4, 2011, 09:57 AM

Thanks guys, thats what I thought but wanted to make sure, its been a while since I last reloaded, and am getting back into it.

**Unclenick** · April 4, 2011, 10:44 AM

Mal gave you the right steer. Cases are specified at their maximum length with a tolerance of -0.020" for most rifle chamberings, so for .270 Winchester, 2.520"-2.540" is the normal length tolerance range. The high speed factory trimmers aren't as precise as a slow-going home trimmer, so the factory just aims for the middle of that range and it's not uncommon to see +/- 0.005 variance in some lots.

The middle of that tolerance range is where the standard trim length comes from, but a lot of folks with more precise gear actually trim down to minimum so they don't have to trim as frequently. The RCBS X-die actually requires you to trim to minimum before your start using it, then its design limits growth to the average trim length thereafter with no further trimming required. Lots of choices out there.

edward5759 · April 4, 2011, 05:21 PM

I had a 270 that the cases had to be trimmed to 2.500 just to fit into the magazine.
don't worry about it

April 4, 2011, 09:39 AM	#1
spclPatrolGroup Senior Member Join Date: August 19, 2010 Location: North Dakota Posts: 349	Cases arrived a little short I purchased some new Winchester brass in .270, minimum case length is .530 but a couple that came were .529 and one or two were .528, should I throw these out, or are they ok to load?

April 4, 2011, 09:43 AM	#2
mapsjanhere Senior Member Join Date: August 6, 2009 Location: Albuquerque Posts: 2,832	Ok to load, and after the first resizing they'll be the right length. __________________ I used to love being able to hit hard at 1000 yards. As I get older I find hitting a mini ram at 200 yards with the 22 oddly more satisfying.

April 4, 2011, 10:44 AM	#5
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Mal gave you the right steer. Cases are specified at their maximum length with a tolerance of -0.020" for most rifle chamberings, so for .270 Winchester, 2.520"-2.540" is the normal length tolerance range. The high speed factory trimmers aren't as precise as a slow-going home trimmer, so the factory just aims for the middle of that range and it's not uncommon to see +/- 0.005 variance in some lots. The middle of that tolerance range is where the standard trim length comes from, but a lot of folks with more precise gear actually trim down to minimum so they don't have to trim as frequently. The RCBS X-die actually requires you to trim to minimum before your start using it, then its design limits growth to the average trim length thereafter with no further trimming required. Lots of choices out there. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle Last edited by Unclenick; April 5, 2011 at 10:09 AM.

April 4, 2011, 09:56 AM	#3
Mal H Staff Join Date: March 20, 1999 Location: Somewhere in the woods of Northern Virginia Posts: 16,955	Wow! You're right, those were really short! All of my .270 Win cases are easily 2 inches longer than that. 2.530" is a "trim-to" length, not necessarily a minimum length. New cases a few thousandths less are not unusual, but you don't want them a lot shorter than that or the bullet purchase length starts getting to be a factor.

April 4, 2011, 09:57 AM	#4
spclPatrolGroup Senior Member Join Date: August 19, 2010 Location: North Dakota Posts: 349	Thanks guys, thats what I thought but wanted to make sure, its been a while since I last reloaded, and am getting back into it.

April 4, 2011, 05:21 PM	#6
edward5759 Senior Member Join Date: September 15, 2009 Location: Phoenix, AZ. 30 miles from water, two feet from Hell. Posts: 355	I had a 270 that the cases had to be trimmed to 2.500 just to fit into the magazine. don't worry about it