update: oh, snap!! wouldn't you just know it. after i have gone through all of this, friend drew at www.barking-moonbat.com has found two commercial sources for .280 brit sizing dies. laughing. now he finds them!! well, makes no difference, i am gonna go through with my plans, because i think the "jj's brit" just a bit better, and more suited for the ar-15 platform. i may be stupid, but, i am stubborn, too.
for those of you not inclined to punish yourself by hard work, here are the links that drew found to the .280 brit reloading dies. hint: they are expensive. and, i don't know that case fabrication will be all that much easier. and, i think my creation "better."
pick your poison.
(just "click" the picture for a larger view.)
left background: an empty 7mm-08 cartridge case, and a .22-250 loaded with a .284 bullet, for scale.
right background: a .30-30 winchester and a dummy "jj's brit" for scale.
way way back background: stuff, and a 7mm weatherby case found at the range loaded with a .284 bullet, and a 7mm remington magnum, for scale.
the front row: a fired .243 winchester brass case; case run through the sizing die w/ the resizing stem removed, showing neck & case shoulder moved back, & elongated case neck; case w/ "excess" neck removed by "chopping" w/ dremel tool, and cut section of neck lying at case head; case run through the sizing die with the resizing stem in place, to give the neck the proper "inside" diameter for the following trim operations; case trimmed to length, & run through the neck turning operation to remove excess brass material from the neck, it will now be .311" (+ a smidge) in size w/ loaded bullet; and, a loaded round of "jj's brit" with a shortened 130 grain sierra bthp (stock # 1903) at its base.
well, this pretty much shows the labor involved in making these cases, especially when all tools are "hand powered," instead of electricity power.
i want to talk in closing about the bullet involved, the very accurate 130 grain sierra match king (bthp, or, more accurately, "otm.")
"otm" stands for "open tip meplat."
the "meplat" is the tip of the bullet. (no, i don't know what they just don't call it a tip? a mystery to me.) if you will look closely at the tip of an unaltered sierra bullet, (such as in a dummy round), you will see a little hole, a "pin" hole: this little hole goes down for a while into the bullet, and then widens as it approaches that portion of the bullet that houses the lead in the bullet. (the bullet has a hollow cavity there.) the tip is formed after the lead goes in, and then the bullet is run through very precise dies to close the tip up tighter than a ticks rear end vent, except for the little hole. the tip is very very stout, and very strong, and you aren't gonna deform it unless you hit something very very hard. it is not meant to expand.
well, what's the point of this whole discussion.
look at the dummy rounds. people will criticize this round because the neck is too short and the bullet seated too deeply to hold the bullet securely in all the rough and tumble of field use, and before firing.
look at the bullet lying on it's side. it is 1.040" long, and look at the robust & thick gilding material walls, forming the outside of the bullet. the longer 130 grain bullets are 1.154" long. the abbreviated bullet has had .114" of length removed from it by the dremel, about a tenth and 1/6th more of a tenth.
now, this will sound a little confusing, but, it is stated with absolute clarity.
if i need to ever add a little more neck to this cartridge and bullet combination, (which i doubt), to grip the bullet more securely, i shall simply file 0.0150" or 0.0200" off the tip of the sierra bullet, which will do it absolutely no harm. and, then i will have all the neck i need in the world. it is an insurance policy, that file.
caption: nothing could illustrate my points more clearly than these two sectioned cases. the case on the right is a bullet seated to 2.260" overall cartridge length. the case on the left has a bullet that has been "abbreviated" somewhat, and then moved forward to achieve that same 2.260" overall cartridge length. every bit of the case neck grips the bullet at its fullest circumference, ensuring a good grip, and the cartridges effect chamber/powder capacity has been increased rather markedly. my arguments cannot be shown any more clearly, at least, in my estimation.
do you understand?
by shortening the bullet that little bit, i will then be able to move it forward and still be with the cartridge overall length of 2.260", and the neck will have a more secure hold on the full .284" bullet shank diameter.
it is a small point, but one i wanted to make in addition to the rather obvious stages of cartridge case fabrication, while i was here and had your attention.
john jay @ 04.10.2012