I am loading for a friends rifle, 6-284. I am using necked down 6.5-284 brass from Norma that I purchased new. First testing was with 75 gr. V-max and H4350. Worked up using Hodgdon's data from 49gr., stopping at 51.5gr. at 3600fps. Didn't notice anything out of the ordinary untill measuring brass afterward. Using the Hornady tool, the shoulders on fired brass measure .020" longer than new brass. Have only been reloading a couple of years but this gives me pause. The rest of the guns I have loaded for have shown .005" growth or less from new brass. Case head separations don't sound fun. I have used the bent paper clip trick to feel around and dont notice anything but don't really know what an incipient separation would feel like. Visual inspection of the inside of the case doesn't raise any suspicions either.
What do you guys think? Would I be safe to proceed as long as I dont set the shoulders back more than a couple thou, or is one time stretching of the brass by this much enough to compromise it to the point I should abandon the project? Any advice is much appreciated, I can provide more detail if it would be helpful. Thanks.
I think you're on the right track,.
You could back your sizing die off so you aren't sizing the entire neck down but are leaving a false neck just in front of the case shoulder, to keep the case seated tight against the bolt face and then fire form the brass.
Once formed to fill your chamber, only bump the shoulder back a couple thou when reloading and you'll be good to go.
Just ff your brass to the chamber and set your die for the brass to have a snug fit. powdr
That is a powerful round and .020" is too much. Stop, check the headspace on that rifle and correct it if needed. Better to be safe 100 times then dead once. The folks that tell you "all ya gotta do" ARE NOT THE ONES that will be firing the rifle.
I agree with others, you really need to check the headspace.Is this a newly chambered barrel? If so and the gunsmith is nearby I would have him check the headspace.
If you can't get to the gunsmith and don't have a head space gauge set you can use some cellophane tape. Trim the tape to fit on the case head of a new cartridge. Add tape till you get bolt closure resistance, then measure the tape to get an approximate measurement. If it is over .005" the barrel should be setback.
If you can't get to the gunsmith and don't have a head space gauge set you can use some cellophane tape. Trim the tape to fit on the case head of a new cartridge. Add tape till you get bolt closure resistance, then measure the tape to get an approximate measurement. If it is over .005" the barrel should be setback.
This is assuming there is good new ammo available for the rifle, but it's a wildcat chamber. You can't rely on new brass to be correct without checking, and being Norma brass doesn't carry any water in that department. Heck I'm working through a new box of Lapua 6.5 Grendel brass right now that is .010" shorter headspace than it should be.
You only have to worry about headspace once, then the brass is fireformed to the chamber, and will stay that way unless you set the headspace back when sizing the case. No problem.
My father had a beautiful Kimber 22-250 that had a dangerously long chamber. His cases lasted 2 firings, because he didn't understand that you either create a false shoulder, or jam a fireformer into the lands for the first firing, then your brass is GTG for the duration, when sized properly. My brother inherited that Kimber. The headspace is at least .05" too long, but the firing pin must compensate a bit, because it doesn't misfire as often as you'd think it should with new brass and jammed bullets. Sure, one could expect Kimber to build a high-dollar gun right the first time, or to make it right, but....well, I wouldn't count on it, and neither did my brother. Easy fixes.
I am loading for a friends rifle, 6-284. I am using necked down 6.5-284 brass from Norma that I purchased new. First testing was with 75 gr. V-max and H4350. Worked up using Hodgdon's data from 49gr., stopping at 51.5gr. at 3600fps. Didn't notice anything out of the ordinary untill measuring brass afterward. Using the Hornady tool, the shoulders on fired brass measure .020" longer than new brass. Have only been reloading a couple of years but this gives me pause. The rest of the guns I have loaded for have shown .005" growth or less from new brass. Case head separations don't sound fun. I have used the bent paper clip trick to feel around and dont notice anything but don't really know what an incipient separation would feel like. Visual inspection of the inside of the case doesn't raise any suspicions either.
What do you guys think? Would I be safe to proceed as long as I dont set the shoulders back more than a couple thou, or is one time stretching of the brass by this much enough to compromise it to the point I should abandon the project? Any advice is much appreciated, I can provide more detail if it would be helpful. Thanks.
Although that is a lot of stretch, the brass might have started out undersized (not familiar with Norma 284 brass). One, initial big stretch is probably fine. Most brass is going to crack from oversizing and being repeatedly stretched. And my experience with Norma brass is it's usually rather soft brass to begin with so it's a bit more tolerant. You could section a case or two to see if the dreaded incipient separation is present just to be sure and for peace of mind.
I'm assuming this a custom/rechambered bbl?
Casey
I am loading for a friends rifle, 6-284. I am using necked down 6.5-284 brass from Norma that I purchased new. First testing was with 75 gr. V-max and H4350. Worked up using Hodgdon's data from 49gr., stopping at 51.5gr. at 3600fps. Didn't notice anything out of the ordinary untill measuring brass afterward. Using the Hornady tool, the shoulders on fired brass measure .020" longer than new brass. Have only been reloading a couple of years but this gives me pause. The rest of the guns I have loaded for have shown .005" growth or less from new brass. Case head separations don't sound fun. I have used the bent paper clip trick to feel around and dont notice anything but don't really know what an incipient separation would feel like. Visual inspection of the inside of the case doesn't raise any suspicions either.
What do you guys think? Would I be safe to proceed as long as I dont set the shoulders back more than a couple thou, or is one time stretching of the brass by this much enough to compromise it to the point I should abandon the project? Any advice is much appreciated, I can provide more detail if it would be helpful. Thanks.
Although that is a lot of stretch, the brass might have started out undersized (not familiar with Norma 284 brass). One, initial big stretch is probably fine. Most brass is going to crack from oversizing and being repeatedly stretched. And my experience with Norma brass is it's usually rather soft brass to begin with so it's a bit more tolerant. You could section a case or two to see if the dreaded incipient separation is present just to be sure and for peace of mind.
I'm assuming this a custom/rechambered bbl?
Casey
Casey, custom chambered McGowen bbl.
Two nights ago I did section a case to get a good look. Looks good, no visible stretching in the case walls. Wish I would have thought to jam the bullets on the first firing but after seeing the sectioned brass I'm confident I can proceed safely.
As an aside, reloading advice can be scary. One guy at work said as long as I'm not blowing primers I'm good to go, and that since it's a mauser action I have nothing to worry about anyways. Another told me not to worry, he sets his shoulders back .020" after every firing. I'm glad I did as much reading as I did before I got started reloading