I need some help in the loading room

[archerforkids]

But here’s the thing I don’t understand. If a sized case clothes perfectly fine how would a small base die solve the neck issue. After sizing it’s flawless, the second I seat a bullet it won’t close at all. There is very little resistance on seating and no notable changes. The only dimension that should be changing significantly when seating at that point should be the neck. How would a small base die clean this up?

I could be absolutely wrong friend. But....eliminates one variable at no cost.

 

[Matt_3479]

I could be absolutely wrong friend. But....eliminates one variable at no cost.

No not saying you’re wrong, I’m just trying to wrap my head around it. Im open to everything right now as I’m stuck. I’m just struggling to grasp how seating a bullet with minimal neck tension is causing the brass to change in the body?

 

[Ringostar]

It has nothing to do with the neck tension of your loads. My understanding is it happens from resizing. Think about this. You fire a round and it expands to your chamber. Then you run it into your die to resize it. The die contacts the side walls first, pushing them back in. The squeeze has to move the brass somewhere. The farther it goes into the die, it start to move towards the shoulder.

 

[Ringostar]

If you back up a sizing die a half turn, so that it doesn’t contact the shoulder. Then measure a fired case from base to datum. Then run it into the sizing die, and measure again. The base to datum will grow in length, from squeezing the side walls in. Now if the die is in the proper adjustment, this still happens until the die contacts the shoulder. So that continues to move brass into the neck.

 

[jackieschmidt]

I have fired thousands and thousands of 6PPC, 6BR, and 30BR rounds over the years, and have never seen necks get any thicker.

From what the OP has said, I don’t have a clue what the problem is since he doesn’t know what diameter the chamber’s neck is.

 

[Matt_3479]

I have fired thousands and thousands of 6PPC, 6BR, and 30BR rounds over the years, and have never seen necks get any thicker.

From what the OP has said, I don’t have a clue what the problem is since he doesn’t know what diameter the chamber’s neck is.

My reamer print just came in actually! So it’s not the neck so it has to be in the shoulder or body.

 

[Sundown]

Matt... A friend came into the shop one day and was having the same problem you're having. Turned out he switched brands of bullets and all he had to do was seat the bullets a little deeper. He Killer a 15 point non-typical that year... Maybe your problem... try it!

 

[rwj]

My reamer print just came in actually! So it’s not the neck so it has to be in the shoulder or body.

Are you using a full length die (one piece die that resizes both the case body and neck) or a body/bushing die? If the latter, have you measured the neck OD near the shoulder/neck junction? This area will not be sized by a bushing and is a likely area for a donut to form after multiple firing cycles.

 

[Matt_3479]

Are you using a full length die (one piece die that resizes both the case body and neck) or a body/bushing die? If the latter, have you measured the neck OD near the shoulder/neck junction? This area will not be sized by a bushing and is a likely area for a donut to form after multiple firing cycles.

I’m using a full length bushing die. I measured for a donut and it doesn’t seem to be the problem. I loaded up a few and coloured with a marker and got no reading. So I put polish over the cases and chambered it and it pushed all the polish and stopped dead at 1/2 down the body of the brass. The polish on the neck and shoulder was untouched. According to the reamer print it isn’t anything to do with the neck, and according to the marker/polish it has nothing to do with the shoulder.

It seems that as I’m searing the bullet now it’s blowing out the body of the brass 50% the way down the body. I’ve heard of measurements changing at the .200 datum line but it’s much higher than that and the .200 datum line measures fine. Some how there’s enough pressure seating a bullet now or something in the brass has changed after 7 firings that it’s now blowing out the body in the Center as I seat a bullet.

My smith has a small base die I’m going try, i also ordered different size mandrels to reduce neck tension even more and I will seat with dry lube to reduce seating force and see where this takes me.

 

[Alaska Bush Man]

Set the shoulder back on case just 1/4 turn on your sizer die and then test the brass in your gun until it cambers smoothly. Trim to spec afterwards.
I only crimp bullets with Lee Factory Crimp Die !

 

[Matt_3479]

Set the shoulder back on case just 1/4 turn on your sizer die and then test the brass in your gun until it cambers smoothly. Trim to spec afterwards.
I only crimp bullets with Lee Factory Crimp Die !

The brass chambers perfectly fine after sizing as it stands and I don’t crimp anything

 

[rwj]

It seems that as I’m searing the bullet now it’s blowing out the body of the brass 50% the way down the body. I’ve heard of measurements changing at the .200 datum line but it’s much higher than that and the .200 datum line measures fine. Some how there’s enough pressure seating a bullet now or something in the brass has changed after 7 firings that it’s now blowing out the body in the Center as I seat a bullet.

My smith has a small base die I’m going try, i also ordered different size mandrels to reduce neck tension even more and I will seat with dry lube to reduce seating force and see where this takes me.

I would have expected the case shoulder to collapse before bulging the case body. Is it correct to state that the seating die does not support the case body? Reducing neck tension via different mandrels is a good idea. Please advise the outcome.

 

[Matt_3479]

I would have expected the case shoulder to collapse before bulging the case body. Is it correct to state that the seating die does not support the case body? Reducing neck tension via different mandrels is a good idea. Please advise the outcome.

I fully expected the neck or shoulder to collapse, bulge, swell, or change well before the body as well!

My smith is going send me his small base die and im going to try it. I’ve ordered different mandrels to reduce neck tension and going to try that as well! I was speaking with a local guy at the range today and he believes something may have changed with my annealing process whether I had the flame too low or too hot and softened the body too far down. Now when I seat a bullet he believes it’s swelling the case body

 

[Mulligan]

When you chambered the rounds that were problematic, how did they eject after firing?

CW

 

[Matt_3479]

When you chambered the rounds that were problematic, how did they eject after firing?

CW

Normal. I visually inspected them but unfortunately like a dummy didn’t take measurements and all. I resized, tested the brass, it was fine and then seated and same problem. I wish I took more time with the fired brass

 

[WVRJ]

make sure your seating die isn't screwed down a little too far.If it gets screwed in too far and the brass goes against the crimp shoulder in the seating die and the bullet doesn't have a crimp groove,you can buckle the case a tiny bit and make it hard to chamber and extract.Back the seater die out one turn to make sure.

 

[Matt_3479]

make sure your seating die isn't screwed down a little too far.If it gets screwed in too far and the brass goes against the crimp shoulder in the seating die and the bullet doesn't have a crimp groove,you can buckle the case a tiny bit and make it hard to chamber and extract.Back the seater die out one turn to make sure.

I did that early on and again 2 nights ago. My buddy was trying to help me figure it out and he was convinced it was that at first as well

 

[divingin]

In my rifles, brass grows in both length and thickness.
I find I have to turn the brass again after a few firings.
CW

Funny; mine's the opposite. For my short range, no-turn barrel, brass that was 13 to 14 thousandths out of the box is now measuring about 12. This is after 15 firings. I don't typically run my loads very hot though.

 

[ronemus]

In my rifles, brass grows in both length and thickness.
I find I have to turn the brass again after a few firings.
CW

This is my experience also.