Here's my situation: I had to remove 22 cases out of 50 tonight due to case separation. These are .41 magnum cases (Project 41) on their 5th. reload. I have my die adjusted so I only reform the first .66" of the case. I was hoping to keep the cases as tight as possible to my chamber. It turns out that right where the die stops is where the cases have a ring around them. I've never encountered this with a bottleneck case before. The problem was brought to my attention at the range Saturday on my last set of rounds with 210 grn. Hornady's and 22.7 grns. H110. The first round rocketed at 1865 fps, which was over the max I was expecting to see. So, I checked the case as it came out of the barrel; no sticking, nothing abnormal with the primer or rim, then I saw the ring around the shell. It looked as if I had taken a pipe cutter the whole way around the rim, just not the whole way through.

Well, being the curious soul that I am, I chambered the next round and squeezed the trigger. 1857 fps, and the same ring around the case only not as pronounced. Then I knocked over the first case, which promptly split in two pieces when it met the concrete floor. WOW! Case thickness at the point where the ring was is all but non-existent, and a perfectly clean break. The remaining three rounds were not fired.

Now, I have two questions: 1) Is 5 reloadings an acceptable life span for straight wall cases? and, 2) Are my cases being destroyed because my dies are set wrong? (It appears the metal is being worked in the area where the ring is showing up).

One adder: Ambient temps were in the mid-80's and barrel temp was 83.5 to 85 degrees when this all went down.

That load is a lil stout! I have seem max loads around 21 grains of H110 with a 210 grain bullet for the 41mag. I just chrono'd my 414 Super Mag loads and they are running 1850 fps with a 210 grain bullet at 27.0 of H110 in a 12" barrel!

The ring that you speak of is the case stretching and then seperating. I have experienced this in the 41mag but it is after 12 or more loads typically.

I full length size straight wall cases as i have never seen any accuracy improvement from a partial resize, a few times the accuracy even became worse.

Evening Mike! Even with that load, I still liked shooting it! And, yes that is a stoudt load, and accuracy proved I was only burning powder.

I've just never seen one split where this one did, is almost right inthe middle of the case. (.622" from the rim to be exact)That leaves .659" for the other piece. It just hurt me to lose that many cases all at once, the last mass failure I had was with 30-30 shells that were formed for my 7-30 - at least they went into the 20's for me.

That velocity was a jump from the previous 5 shot average of 1775 fps - which is why I say it was a little higher than I was expecting. I thought with a .3 grn powder increase I'd be in the 1790's, not well into the 1800's.

[ 07-29-2003, 06:57: Message edited by: T/C nimrod ]

LOL! Yea, that is some SERIOUS velocity outta the mag. Your barrel is a 14"?

Mine split in the same place. I have tons of brass for the mag now but still hate throwing it away, LOL!

I will be working with the 414 some more as i think i should be able to get close to 2k fps with the 210's. I am also going to try some of the Remington 200's, soon! I need a bullet that will rip a woodchuck in half like the 444 and nosler's 240jhp!

[ 07-29-2003, 07:17: Message edited by: MSSmagnum ]

Yeah, 14". It was slighly amusing to see my setup at the range on Saturday: wind flags out to 70 yards, chrono set-up at 12 feet with the remote reader on the bench, a Fluke 52II temperature meter w/one lead hanging at my front rest and the other lead(clamp) on the barrel just after the forend, notebook open, spotting scope on the bench, and an insulated cup full of grape juice.

You'd think I spent the night!

Oh, forgot the timer. I wanted to see how long it took for the barrel to cool down after each shot. I figured that was the only way to keep my loads consistant, keeping a 3 degree temp difference between the barrel and the surrounding air.

Your load is a little on the heavy side, I have loaded up to 22.9 grains before running into pressure problems.

Your cases are being work-hardened, and with that load, 4 or 5 loadings is about all you can expect...

Hey Steve, I was going to contact you on this one, if you didn't post. Have you seen any issues with partial resizing straight wall cases? I started only resizing the area that holds the bullet on these shells, so the case(s) fit my chamber like a sleeve.