.270 runout problems

[mgrs]

Not a competition related topic, but I am getting terrible runout loading .270.

Equipment:

Lee Classic Press

Lee FL sizing die and standard seat die

Federal once-fired, Prvi once- fired

Hornady Interlock 130gr flat base

Technique- FL size, tumble, load. When seating, I guide the bullet all the way into the die, seat part way, rotate 90*, seat part way rotate 90*, etc. After seating, I back it out and rotate 180* to seat again.

Observations:

Runout (measured just forward of the cannalure) is different from federal to Prvi brass:

Federal runout: .015-.023

Prvi runout: .006-.010

Seems like it should not be this bad. Some are difficult to chamber, and the ogive shows where the off-center bullets hit the chamber going in and dinged the jacket. I tried the lee factory crimp die that was included as it claims to reduce runout, but crimping has no effect. For what it is worth, I measured the runout of once fired cases and it is .002 or less.

My only other experience loading rifle has been 5.56 on my xl650 and .30-40 on the lee. With lee dies and brass of the same lot, I am getting .002-.004 out of the 5.56 and about the same on the .30-40, no special seating technique.

Should flat base bullets be more likely to "run out?" I've noticed seating was tough, as if the neck was not expanded enough. Perhaps the neck is being smashed in the difficult seating?

Edited September 23, 2014 by mgrs

[bigedp51]

More ammunition is reloaded and has excess runout for the simple reason the decapping rod/expander button is locked down off center.

1. Remove the decapping rod from the die and full length resize a case and then check your case neck runout, if the case has very little runout go to step 2.

NOTE: If you have excessive runout in step 1 the case most likely has uneven case wall thicknesses and warped when fired. (warped banana shape case)

2. Reinstall the decapping rod/expander button and full length resize the case and check the neck runout again, if the runout increases your expander button is not centered and is pulling the case neck off center. Look for dings in the case rim and extractor groove, this can on the down stroke cause the case to tilt in the shell holder and pull your necks off center.

3. After resizing and minimal runout and moving to bullet seating and you get runout then there is a seating problem.

So set up your dies in steps and find and eliminate at which step the alignment problem starts. The military considers anything under .003 match grade ammo for competition in military matches.

You can also place a rubber o-ring under the dies lock ring and only finger tighten the die, this allows the die to "float" and self center in the press threads. (or buy Lee lock rings with the o-rings pre-installed)

I also place a rubber o-ring under the decapping rods lock nut and this also allows the expander button to float and self center in the case neck.

Forster resizing dies have a flat rubber washer under the decapping rod/expander button from the factory. And the expander button is mounted high on the decapping rod, as the case is lowered it contacts the expander button while the neck of the case is still inside the neck of the die. This reduces neck alignment errors during full length resizing and you can adjust any sizing die this way "BUT" you will loose the ability to remove your primers. The fix for this is a universal depriming die.

Below are two different type runout gauges, I use the RCBS gauge for die setup and checking case neck runout, and then for the final loaded bullet runout check.

The Hornady concentricity gauge in the left rear is the "enforcer gauge" for bending warped brass that has unequal case wall thicknesses.

Meaning you can't make a silk purse form a sows ear and if you have bad warped brass you have to beat it into submission.

So again, find out at which stage the runout problem starts and "try" and fix the problem.

And some things will cost you to fix your runout, I bought a brand new Remington 700 that drove me nut reloading for it. And the problem was one locking lug was not making equal contact causing the bolt face to tilt when fired and this cause all the fired cases to have the base of the case to no longer be 90 degrees to the axis of the bore. Meaning my cases looked like the photo below AKA the leaning Tower of Pisa.

This was a very costly problem, my wife in the photo above said we had to go on a Mediterranean cruise before I got the rifle fixed, by this time I was broke so I traded the rifle to my son who doesn't reload for a S&W model 29 with a five inch barrel.

Now all the hair on my knuckles is gone, my right arm has a hair line fracture and I still have lights flashing before my eyes. So let this be a reloading warning, never load use a max load of H110 in a five inch .44 magnum to fix a runout problem.

[dauntedfuture]

Mgrs,

That's some great information to get you started. I would ask you to consider this: What kind of accuracy are you getting now with what you have? What kind of rifle are you shooting? What is your accuracy requirement? If you are shooting a factory .270 hunting rifle with a skinny barrel I suspect that you are going to get 1.5-2 MOA. Consider that this is most likely with hunting bullets that are not match bullets. If you plan on shooting 300 yds on deer size game, I suspect that that's plenty good for what you need. IF you are shooting hunting bullets in a factory hunting rifle, reducing runout from .01 to .000 will not make the rifle go from 2 MOA to .25 MOA. It might go from 2 MOA to 1.5 MOA or something along those lines. I also suspect that your lee press has lots of flex and the PV brass is inconsistent but im not sure.

[Steve RA]

Somewhat along the lines of the post above, loosen the decapping rod and the die slightly - so they both float - and run a case up into the die and then tighten up the die lock ring and the decapping rod nut and see if this helps line things up better.

Also you might try chamfering the inside of the case neck so there aren't any little burrs or anything to impede the flat base bullets from seating straight.

[fastshooter03]

Is the brass OK(runout) before u seat????

Nick

[Powder Finger]

also does the seating plug touch only the ogive of the bullet, it should not touch the point of the bullet.

[fastshooter03]

Also make sure you r not contacting the crimp part of the die(if so equipped) while seating=bad...

Run the longest case length up and turn seater down til contact then back off a little

Nick

Edited October 7, 2014 by fastshooter03

[mgrs]

Gents,

First I would to apologize for taking so long to follow up on this thread. I was overcome by events at work for a few weeks.

You provided some outstanding information! Thanks to your help, I found the culprit (see below).

To clarify, I am not looking for zero runout "perfect" ammunition. It is, however, so bad right now, that some won't even chamber. The ammunition is being reloaded for a Steyr-Mannlicher Professional carbine with full stock. Not exactly a bench gun, and the only bench time it sees is for load development. I'd still like to see 1-2 minute predictability on the first round. The bolt uses rear locking lugs, but everything about the rifle is so well made, I would hope the lockup or chamber are not to blame!

Fired Prvi brass is coming out straighter than it went in. Factory Prvi .270 runout is averaging .006. Fired Prvi is coming back .002-003 before sizing.

I am already floating the die (lee dies), so I removed the expander. Case necks are staying straight post sizing without expander.

Next, I put the expander back in. Prvi cases are coming out of the full length die (with neck expander) at .010-015.

Now that we have identified where it is happening, let's check the runout of the decap/expander when removed from the die body: .001. That seems good enough, leading me to think that either the shell holder is off, or the lock nut threads are tapped into the die body off center.

I may try different dies, or just stop reloading for this rifle altogether as I almost never shoot it.

[dauntedfuture]

If your ammunition is not chambering for some reason its not excessive runout that is causing the problem. I suspect you have other serious issues to contend with. Until you figure this out, don't worry about the .006" runout. I suspect that if fix what ever the other issue is some of the runout will resolve itself. If you cant chamber ammunition and you are FL sizing make sure you can chamber your sized brass, if you cant do that, screw the die in a little more and try again until you can. Now, you are going to need an expander ball in your dies to open the case neck back up for the bullets and it needs to be .306 or so ID. You need to center the expander ball inside of the die, you can look at the previous posts to tell you how to do this. I don't use much of any lee stuff but I suspect that there is something not adjusted correctly.

[mgrs]

Daunted-

It was the runout on some rounds that was in excess of .015 that resulted in the failures to chamber. This Steyr rifle has a tight chamber as is, and combined with the abrupt ogives on the hornady 130gr interlocks that I am using, is what I think is giving me trouble. I'd be perfectly content with a .006 average for this purpose, but it was much worse than that. I tried seating deeper, as in well below book OAL for that bullet, but it made no difference.

I think I am FL sizing enough- the die is screwed down all the way so that ram bottoms out on it when I size. Sizing without the expander is fine- it's neck expanding that is giving me trouble. The way lee dies are made, I am not sure if there is a way to float the neck expander and still have it in tight enough to work.

I settled on buying an M die and using it to neck size. I use one on .30-40 for cast bullets with excellent results.

Thanks all for the advice- the tips on floating dies were excellent.

[dauntedfuture]

What ever works. An M die is an expander die not a neck sizing die. You can size without the expander ball and then run through an Mdie and I think that's what you are doing but to be clear you are expanding the neck, not sizing it.