Home Forums Hunting & Shooting Ask The Gunwriters JB, what do you make of this?

Did you by any chance resize the new Winchester cases before you loaded them?

Yes Sir i did. I did it to round out the necks mostly. They came a little distorted and i wanted to get them even again. Is that a bad thing? I hope not, but i didnt want to gouge the bullets when i seated them.

You may have the sizer screwed to far down creating a headspace issue would be my guess but I'm sure John will get it figured out.

Rounding out the necks is one thing, but if you full-length sized the new cases you probably shortened them slightly, due to your die being set improperly, as 28lx hinted. That's why you're getting case-head cracks.

Full-length dies should be set so there's a tiny bit if resistance when you close the action. If you just screw 'em down until the die firmly contacts the shell-holder, many dies will size cases so there's a slight amount of excess headspace. When the round goes off the case stretches enough to crack or even totally separate--which is exactly what you've been seeing.

A lot of handloaders believe this cracking is due to excess pressure, but in bolt actions it isn't. Instead it means the cases have been sized too short.

There are several ways to set a full-length die, some even involving buying new measuring tools--and many handloaders love to buy new tools. But it can also be done by screwing the die down so it contacts the shell-holder, then backing it off half a turn. Resize a FIRED case that isn't cracked, then try it in your rifle's chamber. Chances are it won't fit, or will chamber hard. Screw the die in SLIGHTLY, then size the case again, and see if it fits the chamber. Keep repeating this as necessary, until the case will chamber with a very slight amount of resistance. Reset the lock ring on the die in that position, and your problem with cracked cases and head separations will go away.

If you want to round-out dinged necks on new brass, just run the neck over the expander ball. There's no need to full-length size the case. That was done at the factory.

Ok, i should mention that the dies are set properly. They dont touch the shellholder. The only resistance I got on the stroke of the ram was when the case hit the expander ball.

I will try adjusting the die until i get the slight resistance I need to make sure it is a tight fit in the chamber rather than an easy fit.

Thanks John!

Another thought on this is what type seater die are you using? If you are using a standard seater that comes with the die set it is possible that a crimp is being placed on the case mouths. Also at this point in your loading career I wouldn't use the marking of a cleaning rod with bullet in chamber then measuring to the bolt face as a way to determine the max bullet length. Think Barnes recommends their bullets be seated at 50 thousants off the lands to start and go shorter from that, not longer.Rick.

I use an RCBS basic seater die.

I dont have it adjusted down to crimp. I set it a long time ago and have never adjusted anything but the seating height adjustment. I did get the loaded rounds i did not fire out and measure them at the neck. they did not move more than .0002" from one to the next, and end to end on the neck. I believe that means that there is no crimping going on. I could be wrong.

Ok, the group sizes went as follows...

57 grains IMR 4350, Fed. LR match primer, W-W cases, second loading...

1. 2827 fps (sticky bolt lift, split case head)
2. 2806 fps (sticky bolt lift, pancaked primer, split case head)
3. 2839 fps (shiny line around case head)

2824 fps Ave. .782" group.

I did not fire the other brass loaded to 57.5 grains after splitting two of three rounds loaded with less powder than the ones i had left to fire.

58 grains of IMR 4350, Fed. LR match primer, new W-W cases

1. 2862 fps (no bolt issues, case and primer look fine)
2. 2869 fps (no bolt issues, case and primer look fine)
3. 2861 fps (no bolt issues, case and primer look fine)

2864 fps Ave. .649" group.

58.5 grains of IMR 4350, Fed. Lr match primer, new W-W cases

1. 2885 fps (no bolt issues, case and primer look fine)
2. 2889 fps (no bolt issues, case and primer look fine)
3. 2870 fps (no bolt issues, case and primer look fine)

2881 fps Ave. .773" group.

59 grains of IMR 4350, Fed. LR match primer, new W-W cases

1. 2915 fps (no bolt issues, case and primer look fine)
2. 2915 fps (no bolt issues, case and primer look fine)
3. Error... The wind blew right as i was firing and moved the chronograph...

2915 fps Ave. .320" group.

John, after taking several of the fired cases and trying what you suggested, i found that even after adjusting the die out two full turns, and only hitting the neck on the case about 2/3 of the way down, the FIRED cases still chamber just as smoothly as new brass.

What do you make of that? I heard tell that it takes a firing or two sometimes to make brass fit a chamber, but i dont know what i should do with my dies in the mean time. adjust them down so the whole neck is resized, or just leave them where they are?

That's what happens when none of the body of the case is sized, which is exactly what happens when the sizing die is backed way off--as in 2 turns. Basically, you are only neck-sizing the cases.

When the sizing die is backed off only 1/2 turn (which is what I suggested, not 2 turns) then the case body is partially sized. This often squeezes the shoulder a little further forward, the reason you'll feel resistance when a slightly-sized case is chambered.

Often partial sizing, such as turning the sizing die 2 turns up, results in fine accuracy, and prevent the case separations you experienced. But if you fire the cases several times they'll resist chambering, and you'll need to full-length size them--correctly.

Ok John, i failed to mention in my above post that i did 6 different cases, all fired in the Remington's chamber, starting with 1/4 turn, and moving my way up to 2 full turns out.

In all of the cases i tried in the chamber, none of them gave me any resistance.

With this knowledge, where would you suggest i set my dies?

You might just leave the die backed off two turns for now, and see how the rifle shoots.

Right. I will give it a shot and see how it works from there.

Just a thought you might try. Use some unfired brass, don't size, a moderate load of a powder of your choice, use a cheap bullet if you have one, and seat it into the lands. Just try three cases and then reload them with one of your test loads. This will fireform your brass to your chamber. After having head separations on second loading, I am thinking the chamber is a bit long, and the first firing is stretching too much. Having the bullet in the lands will keep the case head against the bolt face and reduce the stretching. Worth a try.

Jeff, i will try that too and see what happens.

I noticed that the 59 grain load was leaving me with nice brass, and the 58, and 58.5 grain loads did as well, but the milder load of 57 grains was the one splitting the new brass after two shots.

Kinda weird, keep us informed.