Jacket stretch when reducing

[goblism]

I am wondering how much jacket stretch/lengthening occurs when reducing jackets. I plan to reduce some 308 jackets for 264. I plan to use them with a VLD point form die with a jacket length likely around 1.4" Do you think a 1.2" 308 jacket will stretch that far? What has been your experience with reducing jackets in regards to increased length?

[257]

well if you reduce it down it has to go some where a lot would depend on the wall thickness when you start verses when finished just try it and see if you can get the extra .200 of a inch. I have tried this with diferent ones some came up short of what I wanted others were to long and had to be trimed.

[midnight]

A while back I had a bunch of 308 jackets 1.15 in long of unidentified origin and I needed some 277 jackets. I made two draw dies to draw it to 282 and then to 275. The jackets had tapered walls too so I used them for practice to see how my draw dies worked. I can't recall the length of the 275 jacket but it made a 172gr 277 open tip bullet that was 1.32 in. long. You should plan on having to trim the final jacket because when you draw them down that far, the mouth will never be square. When you draw a jacket down, it's interior volume does't change much so if your don't trim the finished jacket it will produce a bullet of approximately the same weight bullet as the original jacket.

Bob

[Cane_man]

you should be able to do that without any problems so long as you anneal it a few times... I take 9mm cases that start at 0.390 and draw them down to 7mm at 0.280 ready for swaging... you may have to trim the cases first, but you wont know until you start the draws to see what happens...

[goblism]

Just an update if anyone cares to use this information but a 1.20 308 jacket reduced to a 264 jacket yielded a length of 1.408-1.411 on a sample of 3 jackets.

[257]

sounds like you got what you wanted