look at this brass, tell me what you think.

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mewachee

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Too much pressure.

That round circle on the headstamp is brass flowing back into the hole for the ejector and when you open the bolt (probably difficult to do) it's shearing off the high spot making it shiny.

If these are handloads, you're doing 'em wrong. LOL

Ed
 
Ejector marks from higher pressures and some cratering on some primers. Did you load these?
 
Are these hand loads or factory rounds? The raised circle is where the brass flows into the extractor groove, a sure sign of over pressure, along with what looks like cratered primers. Is there anything more you can share on this?
 
Okay, here is the deal.

Brand new Remington Sendero 7mm ultra. These are the first break in shots, shoot one clean. I shot this box, then started another before I saw this problem.

This box is from one store. It is remington ammo, 140 grain core-loct.\

The next box, different store, reminton ammo, 150 sciroccos.

This problem got worse, I think because it is a head space problem.

http://www.thehighroad.org/showthread.php?p=6789977&posted=1#post6789977
 
Maybe make sure there is not excess lubricant in the bore. Other than that contact the rifle maker to verify the chamber/headspace if it is a concern. I don't know what 7mm brass is suposed to look like.

PS. I don't see any primer flatening from the pictures. That's good. My AR15s and other AR15s show this type of ejector mark with 5.56 ammo FYI.
 
The primers were cratering. I see the conclusion of high pressure, but the fact that these signs increased in as I shot. Athough it is hard to see on the pictures every piece of brass had the problem. A primer fell out of one.
 
Cratered primers
Brass flowing into ejector hole
Primers falling out.

For some reason you are having pressure problems. Stop shooting until they are fixed.
 
You have excessive pressure. If you had head space problems one would expect to see web thinning and or head separation. There should be brass flow and neck stretching with excessive head space.

Put 2 pieces of scotch tape on the head of a cartridge...one on top the next. Trim the tape with a razor blade or exacto knife so that it is exactly the diameter of the case head. Insert the cartridge into the chamber and try to close the bolt. If it closes it should have more resistance. If it closes easily add another piece of tape and trim. Keep adding tape until it won't close. Scotch tape is roughly .002 thick. IN a properly chambered rifle I like to see it begin to close on 1 piece and resist closing on 2 pieces. This will give you some idea and works as a poor man's go / no go gauge.

Additionally you might use a dial caliper and measure your fired brass from the head to the neck opening on a new load vs a fired case. Make note of excessive growth in case length. Measure from the case head to the base of the neck..look for excessive growth.

You might also chamber a load and then remove it. Check the bullet for scratches from the rifling having engraved the bullet ogive. It may be that the bullet is firmly against the lands on firing. It could be the rifling throat wasn't cut deep enough to properly chamber. Also look at the case neck for scratches on the brass. This could indicate that the chamber reamer is cutting an undersize neck and thus the brass cannot expand to allow the bullet to freely exit the case. It could literally be making the case neck grip the bullet causing pressure to skyrocket. I would do a chamber cast of the barrel and measure the chamber neck dimension and compare to the loaded cartridges. You should have at minimum .002 tolerance at the neck to allow for brass expansion during firing.

In the end..call Remington and check with them regarding the rifle AND the ammo they are selling. You should not have brass flow into the ejector hole or primers THAT flat with cratering.

Resolve this problem before you shoot any more. While the Remington action is tough...you shouldn't press your luck. It may be that Remington has generated some over max loads or are using brass that is too thick in the neck.

Cheers
Mac.
 
I agree with what has been said. I like to load ammo on the hot side sometimes. But, I don't want to see any of that, especially the ejector mark.
 
You have excessive pressure. If you had head space problems one would expect to see web thinning and or head separation. There should be brass flow and neck stretching with excessive head space.

Put 2 pieces of scotch tape on the head of a cartridge...one on top the next. Trim the tape with a razor blade or exacto knife so that it is exactly the diameter of the case head. Insert the cartridge into the chamber and try to close the bolt. If it closes it should have more resistance. If it closes easily add another piece of tape and trim. Keep adding tape until it won't close. Scotch tape is roughly .002 thick. IN a properly chambered rifle I like to see it begin to close on 1 piece and resist closing on 2 pieces. This will give you some idea and works as a poor man's go / no go gauge.

Additionally you might use a dial caliper and measure your fired brass from the head to the neck opening on a new load vs a fired case. Make note of excessive growth in case length. Measure from the case head to the base of the neck..look for excessive growth.

You might also chamber a load and then remove it. Check the bullet for scratches from the rifling having engraved the bullet ogive. It may be that the bullet is firmly against the lands on firing. It could be the rifling throat wasn't cut deep enough to properly chamber. Also look at the case neck for scratches on the brass. This could indicate that the chamber reamer is cutting an undersize neck and thus the brass cannot expand to allow the bullet to freely exit the case. It could literally be making the case neck grip the bullet causing pressure to skyrocket. I would do a chamber cast of the barrel and measure the chamber neck dimension and compare to the loaded cartridges. You should have at minimum .002 tolerance at the neck to allow for brass expansion during firing.

In the end..call Remington and check with them regarding the rifle AND the ammo they are selling. You should not have brass flow into the ejector hole or primers THAT flat with cratering.

Resolve this problem before you shoot any more. While the Remington action is tough...you shouldn't press your luck. It may be that Remington has generated some over max loads or are using brass that is too thick in the neck.

Cheers
Mac.
Click to expand...

I don't think I've ever seen a post on THR with more useful, factual information in it than this. I would certainly follow it-

Larry
 
I viewed the pictures posted, and have to say that if this is factory ammo, it seems that it's exceeding SAAMI pressure spec.
Anytime you are extruding brass into the ejector hole, you are exceeding 70,000 PSI +.

It may be a tight neck in the chamber, or a short leade in the rifling causing the bullet to engage the rifling prior to firing. Both conditions will cause high pressure, and with it progressively getting worse, may indicate a build up of soot and jacket material in the neck and/or leade.
Running a fresh reamer in to open the chamber should fix both issues mentioned.

I see nothing to indicate a headspace problem.

I understand that the rifle has been repaired. Will you be shooting it soon to see if is truly fixed?



NCsmitty
 
This happens in both of my M700s. However, the same exact ammo (same ammo lot) does not do so in my Kimber M84 LPT, nor in my Winchester M70 Stealth. Seems to me Remington is chambering their rifles as tight as possible.

Geno
 
Took a while for this thread to warm up.

Thanks, I agree with the info. very useful. I don't always get the best answers to my questions.

The two boxes of ammo of ammo were entirely different (both Rem).

The paperwork says Problem found - M101. But it doesn't say that they really fixed anything.

Will not be able to shoot for the week, but plan on spending a day when I get back.
 
If you have a digital caliper or a micrometer, measure the case head. Should be at or below spec indicated for this ctg. If is not, then call Remington.
 
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