Brass hard to resize

[RonS]

I recently purchased an AR-10, using 168gr Federal Gold Match ammo, I fired 50 rounds through the barrel to break it in, cleaning periodically. The brass showed no sign of high pressure or extractor marks and shot every well at 200 yards, under 1 MOA. When I tried to resize the brass after cleaning it, I could not get the brass go half way into the die, even after running it through my 45 ACP resizing die I could not resize the brass. Did the heat from shooting this ammo through the AR harden the brass? Is my chamber that much over sized? When I shoot this ammo in my bolt gun I have no problems resizing it. Thanks for your comments...

Ron

 

[Ggmac]

Measure your fired brass and compare to your bolt gun . Sounds like a generous chamber. Are your dies std or custom for your bolt gun ?
is your bolt gun using a custom match /target chamber ?

 

[onelastshot]

Measure your fired brass and compare to your bolt gun . Sounds like a generous chamber. Are your dies std or custom for your bolt gun ?
is your bolt gun using a custom match /target chamber ?

I would agree, it sounds as though you've got a generous chamber. Will the brass cycle through the bolt gun after being fired in the other?

 

[Comrade Terry]

Is my chamber that much over sized?

I'm going with that.

 

[ireload2]

If you have an adequate press and lube you should be able to size even oversize brass without difficulty. So what kind of lube and press are you using?

One thing you might do is buy another box of that ammo.
Measure the diameter of the loaded rounds at the body shoulder junction and measure at the pressure ring for about 5 cases. Mark each round with a number 1 to 5. Then fire those in your rifle.
Finally measure each fired case at the shoulder and at the pressure ring. Then tell us what you found.
Youi do not have to guess if your chamber is over size or not.

PS The only thing heat can do is anneal brass. Brass is not a heat hardenable alloy.
The only way brass gets harder is by cold working such as forming or shooting it.

 

[alb]

As has been stated, the right lube can make a world of difference. I resize a lot of Lake City 7.62 that's been fired in machine guns, using a T-7 press. I've tried a number of lubes, but keep coming back to Imperial; it makes sizing effortless for me.

 

[jonbearman]

I agree that even a semi auto with a larger chamber you should be able to size with little effort. I want to know just like the other posters which lube you are using and how much. Try the old stand by rcbs high pressure lube. You don't need hardly any of it near the shoulder and a tiny tiny amount on the inside of the neck and just a tiny amount on the outside of the neck other wise you will get grease dents. You can lube the body with a bit more but the old rcbs liquid grease does a great job with stubborn brass. When you are done get some alcohol and a clean cloth or paper towel to remove the case lube when done or tumble them in untreated corncob to remove the grease. I would also think about getting them annealed if indeed they are that work hardened. Please let us know how this turns out. One last thing if you are using a hand press that is why you are having such a hard time. Get a rockchucker or a lee classic cast single stage press and decent dies and then you should be on your way. Do you know you have to trim to length and chafer each case initially so you cases don't interfere with the chamber of your rifle.

 

[jonbearman]

What brand of AR-10 do you have?

 

[243winxb]

Rcbs lube applied using a pad. Lube the inside of the case neck with an RCBS nylon brush.

 

[dickn52]

I have had this problem with Federal Match before. Local SWAT team gave me their brass from Rem 700's. Never got that brass resized.

 

[RonS]

Gentlemen, thanks for all your thoughts. Where do I start, I have a RCBS Rockchucker press and a Lee Precision classic press, been thinking about the T-7. I use Hornady custom grade bushing dies. I'm using Imperial sizing die wax as well as Sharp Shoot R Precision royal case and die lube, but not together. The AR-10 is a DPMS, the fired brass from the AR will fit the chamber of both my factory barreled Savage bolt guns. There is a slight difference in headspace but the bolts will close with just minimum effort with the fired brass from the AR. Chamber deminsions are virtually identical on fired brass between my bolt gun and AR. The headspace difference is 0.005", the AR being 1.630" and my bolt gun at 1.625" according to my Hornady headspace comparator on two fired cases, I use Lapua brass in my bolt guns. My dies are set to bump the shoulders 0.001" when sized in either my FL or NS dies. The Federal brass was deprimed with a universal deprimer and then wet tumbled in a Thumbler Tumbler before lubricating the cases with royal case and die lube...I'm gonna try the Imperial wax tonight.

 

[243winxb]

Wax buildup- clean die. Change lube.

 

[joshb]

Is it possible that your depriming pin rod has loosened and "dropped" too low?

 

[Shynloco]

Ron,
I've found that Federal Brass has historically been "harder" to resize than most others on the market. But as others have said, use Imperial Resizing or the RCBS Lube 2 and apply a generous coat. Its not your press that is the issue but rather the brass itself. I've used four different presses to resize brass and Federal has always needed that extra UMPF when throwing the lever arm. And yes your chamber on your AR10 can be liberal and the more the brass (Federal) is worked, the more stubborn it can be. That is why I bought a bunch of LC Brass for my son's AR10. It's a lot easier to resize than the Federal Gold Match stuff. But be liberal with the resizing wax and things should come around. BTW, don't waste the Lapua brass on the AR10 which is brutal on brass anyways. Lapua is great brass for a bolt gun, but too soft for the semi's.

Alex

 

[Milo 2.0]

Your Rockchucker every bit as stout as a T-7 will be, I had an oversized chamber in a 338 snipetac, based off 375 cheytac, on some cases it would take 6 pumps to get it all the way into the die, each time I came down with the brass I would have to massage the lube toward the case base. Imperial alone would not do it, I needed a mix of it that rcbs spray lube,not sure what it is called.
I could only size 6-7 cases before I would get hydraulic dents on the shoulder and die would need cleaned, yours not that straight of a case wall, so you may not have that issue.

 

[Cecil S.]

I resize LC brass and it is tough stuff. I found that annealing first helps a lot. The best advice was to back your dies off 2 turns and resize in 1/2 turn steps. This made a world of difference in my process. Pay attention to spring back. Keep at it you will get it.

 

[RonS]

Wow, last night I wiped the that royal case lube off and applied the Imperial wax, night and day. The Royal case lube works fine on any 308 brass that was shot in my bolt guns, that's why I used it with the Federal stuff. I was able to resize all fifty cases in less than 30 minutes. My first AR-10 would chew up LC brass so bad that it wasn't worth picking up off the ground. But this one, is very easy on the brass, in fact that Federal brass looks like it was shot from a bolt gun, that's why I picked it all up. And I would never use Lapua brass in any AR's. I have about a hundred pieces of LC Match brass I'm gonna try in this AR to see which is easier to resize after firing. I want a T-7 for the convenience of sitting up all the dies for a particular cartridge at one time and not having to flip flopping back and forth like I do on a single stage press.

...a 338 SniperTac sounds like a neat little toy

 

[alb]

Another tip with the Imperial is that it removes very easily using the inexpensive microfiber towels that they sell at Harbor Freight; just a quick wipe and it's gone, and a towel will last very a long time. Seems to me to be the easiest method (I clean after depriming and before sizing, so the case is clean at that point and I'd rather not clean it again), and it forces me to take another good look at the case condition, which is never a bad idea.

I really do like my T-7; for my purposes it's just a great press. However, if they'll fit in your Rockchucker, you might want to take a look at the Hornady lock and load bushings, as they certainly take a lot of the tedium out of swapping dies in a single stage.

 

[KMart]

Ron, do you clean your cases prior sizing them?

 

[RonS]

KMart, first I use a universal deprimer before placing them in the tumbler, whether it be the wet or dry tumbler, then I resize my brass. I never put a dirty case in my resizing dies, full length or neck sizer dies.

alb, microfiber cloth...okay! I've been using a damp paper towel to remove the Imperial wax. Also, Dollar Tree sells microfiber towels too.