Uh. Causes for case damage?

[Dishonored]

I was showing Logislan some load work for my LR308 and I started to question my loads because I noticed my label was missing after I got back from shooting.
This picture is of a 5 shot group. 80yards with these rounds.

I got back and wanted to recheck my loads. I pulled 3 loads out of the box (all the same as I shot) I have 15 left I shot 9 total.
They are all at 2.818-2.82 OAL using a 168gr SMK. And remington brass. also CCI primers.
here is the problem. I wanted to double check the powder weight. I only use varget and h4895.
I calibrated the scale twice now and re zeroed. Always comes up to 46.1-46.2gr.
Now since I lost my label I don't know which powder it is and these two powders are identical! So I checked my loading manual. And then noticed these loads are way over the Recommended max for both powders. So I examined the casings. No "over pressure" signs that I can spot but here are some pics of what damage is evident and I don't know what would cause this. Looks like a gash on the back of the round (near primer) some hash marks halfway to the rim and two sets of marks on the neck. Any idea what these are caused by and why with almost 3.4grains over the max there are no signs of "over pressure"?

 

[Leadfoot]

There's your overpressure signs.

 

[Dishonored]

There's your overpressure signs.

.

 

[mickey]

Back the charge down before you blow yourself or the gun up.

 

[mickey]

 

[Dishonored]

This post was typed before mickeys response. That picture is worth a thousand words.


Well no maybe not over pressure signs.
I have this CBC ammo from magtech that is just ball stuff I shot today before the others. Same markings. Just not as predominant.

The gashes are all on the right side in this photo

 

[Ritten]

I don't see what "gashes" you are talking about, but you are definitely WAAAAY overpressure. The wipes on the back of your brass is from the ejector where the case is pressured up against it while the bolt rotates out of battery. The nicks on your neck are caused by sharp feeding ramps and the rub on the outside of the case head is caused by the extractor slipping over the case. Welcome to the world of .308 gas guns....they will destroy your brass.

 

[xmeister]

The 'gashes' shown in the picture above (post #6) are classic ejector swipes. It could be a sign of high pressure, but just as likely soft brass or a rough bolt face/ejector. Under pressure brass flows into the hole occupied by the spring loaded ejector button. When the bolt unlocks and rotates, that 'high spot' gets smeared on the edge of the ejector hole.

It is just one of many potential pressure indicators.

The marks in the middle of the brass body in the first post are merely the brass striking the ejection port. Nothing to worry about.

Get a grip on your reloading procedures before something ugly happens.

Lanny

 

[Ritten]

I also see that you have a nick in the middle of your brass halfway between the case head and the neck. This is caused by the round getting jammed at an angle while the bolt is coming forward pressing it against the lip of the chamber wall. Check to see if your ejector pin is sitting proud of the bolt nose or if it has any sharp edges on it that may be catching the case. If it does sit proud, use a stone or some coarse sand paper to take off .020-.030" and smooth it out. It will help your round to feed smoother. Stoning the feed ramp points will help mediate those notches in your case necks too.

 

[Dishonored]

The 'gashes' shown in the picture above (post #6) are classic ejector swipes. It could be a sign of high pressure, but just as likely soft brass or a rough bolt face/ejector. Under pressure brass flows into the hole occupied by the spring loaded ejector button. When the bolt unlocks and rotates, that 'high spot' gets smeared on the edge of the ejector hole.

It is just one of many potential pressure indicators.

The marks in the middle of the brass body in the first post are merely the brass striking the ejection port. Nothing to worry about.

Get a grip on your reloading procedures before something ugly happens.

Lanny

.

 

[Dishonored]

I also see that you have a nick in the middle of your brass halfway between the case head and the neck. This is caused by the round getting jammed at an angle while the bolt is coming forward pressing it against the lip of the chamber wall. Check to see if your ejector pin is sitting proud of the bolt nose or if it has any sharp edges on it that may be catching the case. If it does sit proud, use a stone or some coarse sand paper to take off .020-.030" and smooth it out. It will help your round to feed smoother. Stoning the feed ramp points will help mediate those notches in your case necks too.

Thanks I will check that myself and have it looked over as well. I do think the feed ramp points need to be sanded down looking at those neck marks.
I appreciate the information and how to fix it.

 

[Sugarbug]

Back the charge down before you blow yourself or the gun up.

Don't be a *****. You got 3 or 4 more grains of wiggle room.

 

[eMGunslinger]

Well the neck on the brass didn't split....yet!


Sent from my iPhone using Tapatalk

 

[CATS]

http://stevespages.com/diagnosingproblems.html

 

[Akajun]

as was said before, way overpressure. My Varget load with 168's for my palma gun and my LR308 is 44 grains. When I was shooting 45 grains I was getting extractore flow and enlarged primer pockets. Back down you wont give up anything meaningful in terms of velocity.