Neck wall thickness for 30x44

F

feffer

Member
Shot in benchrest and hunter bench competition some years ago, but had a years long lay-off. Now I'd like to do some shooting again. My 30x44 barrel is marked .330 Neck. What should my neck wall thickness be...min and max? I'm using GTB 135 and 150 grain bullets which mike .3086 in. I made a chamber cast which mikes .333 on the neck...so that's different from the barrel stamp.

On a related note: I have Redding FL reloading dies, which I probably bought for case forming. But I'd like to use my Wilson .308 neck sizing dies for general reloading, if possible. A measurement shows putting a spacer (prox .185") under the case would push the (shortened .308) 30x44 case into the die about the right amount. Any reason not to do this?
 
Turns out I had Jone's dies for the 30x44 hiding on a shelf, so the die issue is moot.

I'm still a bit concerned about the difference between my chamber cast with a measured .333 neck and the number marked on the barrel of .330 Neck. Cases I set up long ago have .0105" walls, so these would be OK in a .333" chamber neck but too much for a .330" neck. Any reason not to trust the chamber cast?
 
The cast should tell all if done right. Can you have the gunsmith measure the reamer if still available?
 
I'm still a bit concerned about the difference between my chamber cast with a measured .333 neck and the number marked on the barrel of .330 Neck. Cases I set up long ago have .0105" walls, so these would be OK in a .333" chamber neck but too much for a .330" neck. Any reason not to trust the chamber cast?

Make a go and no-go round to determine the probable neck size. Measure two bullets to make sure they are the same size and fashion two neck thicknesses such that you have a go and a no-go load. Make sure the sized cases fit and close easily before you add the bullets. That will eliminate any guesswork and won't take too long to do. Seat the bullets in such that they don't touch the rifling. If you feel anything greater than the empty case felt...it's probably too big. Do this with the spring out of the bolt as well so you don't have to feel the spring.

I hesitated to write this as there may be something I didn't think of....and it would be stupid. I've never done this on purpose but have found my chamber different than specified by the same method....just not in the same order.
 
feffer said:
OK, thx guys...I think that gives me the info I need.
Click to expand...
It would seem to me a chamber cast is more reliable than what is marked on the barrel. People make chamber casts to double check neck size written on barrels. Measure your loaded round neck size to be sure all your calculations are good, be sure to measure largest part (over the pressure ring) of the neck. Remember too much neck clearance may work your brass a little too much but is not a cause of high pressure . Too large a loaded neck diameter for the chamber on the other hand can lead to dangerously high pressures.
I have zero experience with the 30x44 but considerable with the similar 30x47L I run around .003" neck clearance with good success.
Dick
 
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