How thick should my necks be

[David R]

OK, I bought the fatter 30 a while back. I bought the mold for a 7.65 argentine. I loaded 50 with 12.5 red dot and shot the best group ever. Some of the cases were too big from using 270 or '06 brass. I sized the boolits to .314, same as groove diameter. Some of the cases were too big at the neck and the bolt wouldn't close and 2 split I am guessing from overpressure. I bought an outside case neck turner. How thick should the necks be? I used a Brown and Sharp dial caliper to measure and they are .013 to .015 thick. I am turning them down to .012.

Never did this before. They sure are purdy when I am done.

Here is the target hanging up behind the pot. 1 3/8" group.

The coffee can full of scrap boolits and sprues and the ones on the bench are from the last group buy I did. (freekin mess)

5454

[felix]

To give a total clearance of 0.001. Use magic marker on clean loaded necks, and turn bolt gently. If there are any closing marks on the magic marker, go 0.0005 thinner until necks remain black. Check with magic marker after every other firing. If marks re-appear, then redu for another 0.0005 takeoff. Continue for three times. For the fourth time, take off a whole 0.001. Dropping the load down will also stop the neck thickening from firing. ... felix

[NVcurmudgeon]

After I got my full growth, such as it is, 14 1/2. Now that age has wrought a few minor redistributions, 15.

[Buckshot]

.................Good work David. Useually casenecks run from .008 to .011". As Felix describes, fitting to the chamber for our boolit diameter is the hot setup. Many long years ago I had a Rem 788 in 243. I found out I could make brass from 308. Having a cousin who was a Gunnery Sgt in the Co-aah, I recieved a huge quantity on links. For an M60 I guess.

This was way long ago so don't laugh too loud, but I never thought to wonder where all that brass when when going from .308 to .243, hah! I altered some and loaded them up. I even managed to fire some, and the primers looked like silver greenie stickum caps on the bases of the cases.

I finally had one that wouldn't fully chamber, and it wouldn't 'un-chamber' either. That's when I found out that Remington silver brazed the bolt handles on. The cheap so and so's. I managed to remove it via a baseball bat. Pretty moronic, eh? I don't recall at this late removed date how I got it opened and the case out, but I sent it off to the people at Remington.

I got it back with a charge to my folks credit card for rtn shipping, but that was it. I suppose they put in a new bolt (I don't remember) and they noted they installed a new trigger.

.................Buckshot

[David R]

I will try the black sharpie. This thing is going to be powered by a drill. I did about 30 cases and my arms are tired.

Thanks for the info.

David

[eka]

I have necked brass up for a couple of calibers, but not down. I have been thinking of doing the .308 to .243, but was not real clear on how to get the necks turned down to the right amount. It seemed a little intimidating, but the magic marker trick Felix described sounds great. I think I'll have to try that. Thanks for the excellent tip.

Keith

[trooperdan]

Buckshot, you HAVE lead an adventurous life! Do you still have all your OEM parts, and in unmodified condition? After seeing your '03, it would be a wonder!

[Larry Gibson]

How thick depends on whether or not you're "in the rut"!

Larry Gibson

PS; seems NVCurmudgeon and I are the only ones that saw humor in the question......

[Ricochet]

Neck thickness is limited by collar size.

[leftiye]

Naw Larry, the rest of us jist kept our mouths shet (LOL).

Nobody seems to have suggested casting the chamber, and calculating chamber neck minus .002", this minus boolit diameter (also obtained from chamber cast or sluggung) divided by two gives max useable neck wall thickness. Felix's method only works if you can get the cartridge to chamber, this will get you to where it should chamber, and felix will get you from there to where you need to be.

[David R]

I turned 48 of em. This thing is going to be powered by a dewalt or something. They look good, going to load this weekend and shoot em on tuesday. I'll post pics of targets.

I noticed some were thick in the front, some in the middle and all at then base of the neck. All are turned to .012 thick. I have a bunch of fatter 30s lubed with LEE mule snot, sized in a push through .314 sizer with gas checks installed and re lubed.

Only time will tell.

David