fire formed case problem

G

Gina1

Guest
OK guys, this one has me scratching my head.

Here's the problem I've got and any advice, recommendations or explanations would be greatly appreciated.
I've got a Savage 12FCV .223 and have been reloading for about a year now. I'm not sure this problem was always present or I've just become more attuned to the idiosyncrasies of hand loading.
When reloading new brass, the round will fit into the chamber with no effort, and if unfired can be ejected, with no problems or effort.

On the other hand, using fire formed brass, there is a small effort to close the bolt, and it is difficult to pull the bolt back and remove an unfired round. This happen whether using an FL die or a necking die.

Both new brass and fire formed cases, are set to the same specs. Case trimmed to length, cases are FL re-sized, so head space is the same. OCL is the same, using the same type of bullet. Bullet depth is the same.

In looking at an unfired, fire formed reload after it is removed from the chamber, a scuff mark can be seen on the bullet. The orientation of the scuff mark is always on the bottom left of the bullet.

The picture I've attached is not the best, but it does show the scuff mark.

So what's going on ?? Is something wrong with the rifle or am I doing something wrong. ?
Is the chamber out of alignment so that when the brass is fire formed, it now out of alignment?

So what advice do you have...?? Any and all help will be appreciated

Much thanks
 

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Do you have access to a bore scope? I believe the throat is not symmetrical and the lands extend back further at that point. How did you determine your seating depth? Any signs of pressure, is your velocity what you expect? Have you seen the bore scope pictures of the Savage barrel on another recent post on the benchrest forum? I also have a Savage (several) and I have the same problem. I measured the jam length with a Stoney Point (Hornady) gage and then subtract 0.015" or jump 0.015". If I force the bullet in the gage it will slip past the long land and give me a different length and give me a jam condition. Despite that it shoots very well off the 0.015" jump. Have you measured runout? - nhk
 
I checked bullet runout with the Hornady Lock-N-Load concentricity tool. All were with in .001 after adjustments.
I'll ask around at the range to find out about a bore scope. I'm also leaning to a non-symmetrical throat.
Gina.
 
The mark you show may or may not indicate a problem. Except for one factory rifle, the rest of my rifles are benchrest competition rifles, with the chamberings checked for runout

Bona Fides: Some I chamber myself, the rest were done by professionals, either Joel Pendergraft or Dave Tooley, with me standing by, looking over their shoulder, trying to pick up speed tips. Professionals work faster, a lot you can learn. Now that Tooley's gone to a Haas CNC lathe, no more speed tips, but when he was using his old Nardini, it was amazing how fast he could chamber a barrel, with measured results well within what's "accepted benchrest quality" (AKA really damn good).

That said, I see that mark on several of my rifles when setting up to establish/check bullet seating depth. IIRC, only on those that have an ejector. None of them shoot anything with a loaded factory round available, so I can't check a factory-loaded round as a test.

Things you could try, since you're chasing down a mark that may not matter:

1. Advance your seating depth so the rifling makes good, hard marks on the bullets. Ignore the scuff mark. Are the rifling marks even?

2. Strip the bolt of the ejector and extractor. When chambering your test round, push it in as far as it will go by hand (gently), then close the bolt. Push it out with a cleaning rod. Is the scuff mark still there?

* * *

BTW, it may just be the people I hang out with, but I've never used, or heard used, the term *asymmetric* for a chamber that is not centered on the bore. It's too vague. The chamber is going to be round (symmetrical). I can't think of an easy way to get an "oval" chamber using a lathe. Maybe my lack of imagination. It may be round, but a touch too large (poor technique), or round, but a bit off-center from the bore at the point where the rifling begins (poor setup).
 
Hi!.......Your problem may lie in the reloading dies. Borrow another set and resize your fired brass. On the other hand you may want to contact Savage......oval chambers are not rare,IMHO.

Ted
 
Before trying new dies, you should determine if the problem of a small effort in closing the bolt still exists with no bullet seated in the brass. If the effort is still there with no bullet, it is a sizing problem. If the bullet is causing a small effort in closing the bolt, seat the bullet deeper and test.
 
Dennis has it pegged either way.
One more thing to check is..you show what may be land marks on one side of the bullet, is there any scuffing on the tip on the opposite side?
I noticed in the rife accuracy facts book it pointed out that a lot of factory chambers are actually offset.
 
Well...try this. Using a Resized Loaded Round, mark the rim and place it in the chamber(marked side up) and close the bolt. Open the bolt, remove the scuff-marked cartridge, rotate it 180*, rechamber and extract. If there are Two Scuff Marks 180* apart, then you have a misaligned chamber problem.
 
TheoW said:
Well...try this. Using a Resized Loaded Round, mark the rim and place it in the chamber(marked side up) and close the bolt. Open the bolt, remove the scuff-marked cartridge, rotate it 180*, rechamber and extract. If there are Two Scuff Marks 180* apart, then you have a misaligned chamber problem.
Click to expand...
Or more likely, a strong ejector spring . . .
 
Concentric or Symmetric

Charles E said:
BTW, it may just be the people I hang out with, but I've never used, or heard used, the term *asymmetric* for a chamber that is not centered on the bore. It's too vague. The chamber is going to be round (symmetrical). I can't think of an easy way to get an "oval" chamber using a lathe. Maybe my lack of imagination. It may be round, but a touch too large (poor technique), or round, but a bit off-center from the bore at the point where the rifling begins (poor setup).
Click to expand...

OK, maybe a bad choice of words, but when you rotate the bore scope in the throat the lands are longer on one side than the other in the leade. - nhk
 
Another thing you may wish.................

to try, and less initial trouble if you use the sliding-chamber type dies. I usually Batch-Load, so you could try this over a couple days, or just get out 20 formed cases fresh out of the tumbler and load them.

Here's an easy check, dismantle the dies one at a time and clean them well w/some Ronsonol or other lighter fluid and Q-tips, unless you have the long handled swabs.

As you reassemble the dies, leave the springs that power the chamber on the downstroke OUT of the die, assemble and then load as usual.

One of the problems I had was encountered this way, the scuffing was there too, and I know how I caused the problem, by inadvertently bottoming the die body on the shellholder. Another one came that way from the factory.

The reason I say remove the springs is because in both cases I had to 'feel' it, and those springs wouldn't allow that. In the one die, I found an almost imperceptible 'tug', as I was withdrawing the loaded round.

HTH
 
Well..... I can't explain it, but the problem with the scuff mark, was coming from bullet runout. After rotating the the round several times, and rechambering after ejecting it, the scuff mark was always in the same place with new scuff marks over the old ones. The reason I can't explain it is becaue I was using the Hornady Lock-N-Load concentricity tool to check runout. Runout could be adjusted out using the same tool. After adjusting runout was less than .001.
Of all places I found the answer for this was on YouTube. Seems the seating die I was using RCBS competition die is prone to causing bullet runout. (see the video yourself, search "reload dies" can't remember the exact author of the video. Have replaced the RCBS die with the Redding competition die and no longer have the problems.
Ran the Redding die rounds through the concentricity gage and have less than .5 mils out of round/ with no adjustment. With the RCBS die I always had to adjust 5-7 mils.
Went to the range yesteday and group was less than 1" at 200 yards with the new Redding seated rounds. I'm happy now. ;D

Gina... Thanks for all your input guys
 
Some lessons for us all. In your original post, you'd said:

In looking at an unfired, fire formed reload after it is removed from the chamber, a scuff mark can be seen on the bullet. The orientation of the scuff mark is always on the bottom left of the bullet.
Click to expand...

Obviously, this was happenstance. No reason why a chambered round, having a bullet with runout, will always be oriented so the run-out bullet is bottom left.

An for the rest of us, no reason to look at expensive, unlikely fixes before the more common, and cheaper, solutions are examined first!
 
Charles E said:
Some lessons for us all. In your original post, you'd said:



Obviously, this was happenstance. No reason why a chambered round, having a bullet with runout, will always be oriented so the run-out bullet is bottom left.

An for the rest of us, no reason to look at expensive, unlikely fixes before the more common, and cheaper, solutions are examined first!
Click to expand...

How about if the the runout is contacting an offset? - nhk
 
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