Question about FL resizing

[slivoman]

Gentlemen I have a question for you. I just recently started reloading. I have about 700 rounds of once fired PPU brass from two different batches that were fired out of my rifle. I wanted to prep them correctly, and in order to use my Giraud, I had to full length re-size them with my Redding competition FL sizer which does not size the neck. Now i have read multiple times if you are going to FL size your once fired brass, that you should not bump the shoulders more than .003 from the fired size. Most of my brass measured 1.624 using the Hornady head space gauge.

So here is my dilemma, once I setup the die to push the shoulder back .003, I started to resize about 100 rounds. During resizing I noticed some were harder to size compared to others. Once I finished the 100 rounds, my actual head space measurement was as high as 1.623 and as low as 1.617. I realized the brass that was harder to size re-sized closest to 1.621 where the other brass that were easier to size would go as low as 1.617. Is this because of the PPU brass I am using or does all brass do this?? Could my FL die have an issue?

Down the road once I get more experience, I plan on buying either Winchester or Lapua brass, but I don't want to run into the same situation. I appreciate any and all input.

 

[armorpl8chikn]

I can assume you are running this in a gas gun. It won't matter too much. Yes it is probably the Prvi Partizan brass, it is some of the cheapest ammo available so....
Annealing your brass will solve the problem.

 

[wilecoyote]

in my opinion, you can trust in your die_ I can't trust on the cheap brass _ annealed or not, I try to avoid having something I don't trust chambered on my guns, (even pickier if semiautos, and more even if some annealing would be involved) because I have few guns and two eyes only_ If you can , go with "your planned" next brands, or you can spare some dime and go with L.C., if allowed from your caliber's choice and availability_

 

[slivoman]

I can assume you are running this in a gas gun. It won't matter too much. Yes it is probably the Prvi Partizan brass, it is some of the cheapest ammo available so....
Annealing your brass will solve the problem.

Its a bolt gun. The only reason I am even full length sizing is because of my Giraud. Otherwise they would not fit in the Giraud to trim.

 

[FLIGHT762]

Sometimes the brass will react (measure) differently depending on the amount of lubrication during sizing and the duration in the F/L die. Take a couple of the cases that measured out to 1.621-23, re-lube them well and run them again in the F/L die. Sometimes, if you run the brass into the die quickly in and out and the the lube is too thin, it can cause the the sizing to bump a little less. When I have cases that are work hardened, I run them in the F/L die twice, slowly and turning the brass 180º on the second pass it will sometimes work. To cure it though, annealing the brass will do it.

 

[slivoman]

So its normal to run the brass twice? I mean cheap brass that is. I was thinking about running it once through the die without bumping the shoulder at all, then checking my head-space measurement and sorting then by size and finally adjusting the die to bump it to spec. Does this sound like I will get more consistent size?

 

[FLIGHT762]

I am just suggesting you try what I recommended to see if it works for you. Cheap brass or expensive brass, it doesn't matter. Brass that has been work hardened or not annealed properly will react (spring back) differently when resized. You just need to try it to see. If my suggestion doesn't work in getting consistent shoulder bump measurements (within .002") your brass may need to be annealed.

I don't know how you ran your brass through your press. I know from my experience, if I run the brass really fast in and out of the die and with the combination of thin lube, I will get inconsistent sizing / bumping.

I've found running the brass slower into the die, with a well lubed case and a 2 second stop at the top of the ram stroke will give me better results.

 

[slivoman]

Yeah, I did run the brass pretty quick through the die with a normal amount of lube. I will try your recommendation. Thanks.

 

[targaflorio]

What press are you using? I had inconsistent headspace readings on a progressive that went to zero inconsistency with my Redding Big Boss.

 

[slivoman]

I'm using a Redding T7 with Redding dies. I have some Federal brass to prep as well this weekend. I am hoping the Federal don't give me the same issues the PPU brass did.

 

[former naval person]

Annealing probably won't help...the bind is down toward the base is my bet. Lube? I like the castor oil/lanolin/alcohol mix. Works best for me.

 

[Juma]

Bet good annealing will make a huge difference and slow sizing i.e. not bouncing the case in the die.

 

[918v]

PPU has two different cases, one weighing 10grs more than the other. They look identical. I suggest you sort them by weight.

The heavier of the two will have thicker case walls and may be harder to resize. Harder to resize means more springing of the press. The more your press springs the less the shoulder will be bumped back. Hence the difference in headspace.

The way to ensure all shoulders are sized even is to set the die to cam over the shell holder. This will remove any influence press springing may have over the sizing operation. But you want to bump the shoulder only .003". Can't set the die like that using a standard shell holder. So get a Redding Competition Shell Holder set. It has 5 shell holders in five different heights, each .002" taller than the other. They allow you to bump the shoulder in .002" increments while camming over.

No slack, no springing, all shoulders even.

 

[wchartz]

I have been down this road many times with several cartridges. There is one and only one sure fix for this problem. Fortunately it is an easy one. Buy a set of Redding Competition shell holders. They are made in increments of .002" from +.002" to + .010". Set them up as you would a standard shell holder; a positive hard contact between the die and shell holder. Start with a fired case that is tight in your chamber. Using your resizing die start with the .010 shell holder and resize as usual. Try the case in your chamber. Work down from there one holder at a time until you get to the one that allows the acceptable clearance. Record that size shell holder in your notes. None of the above mentioned fixes will work all of the time even with new brass of the same lot. There are just too many variables. Save time and aggravation, buy the shell holder set. Best of all most shell holders are used for several different cartridges.

 

[bigedp51]

As stated above pause for three seconds at the top of the ram stroke, lower the ram rotate 180 and size again pausing at the top of the ram stroke. The spring back rate of the brass can vary with hardness/thickness. Pausing at the top of the ram stroke lets the brass know who is the boss and to stay put after sizing. Doing this you will get much better consistent shoulder bump reading.

The brass got that long with 55,000 psi pressure so give the die a few seconds to force the brass into submission at the top of the stroke.

You need to put the press handle in park for three seconds and not try to go faster than the speed of light.

 

[mdmp5]

If you run across a bunch of surplus brass that was run through a variety of mystery rifles, the dimensions are going to be all different. Some brass will be smaller than your sizing dimensions. When this brass is sized, it may squeeze forward unpredictably, actually moving the shoulder forward, but it may not fill the die, and you will get different headspace readings. Once you fire this brass, it will all be shot from the same chamber, and the next time around your headspace readings will be more consistent.