Pressure signs

[BoomFlop]

I am a new Reloader, and have been having very good success with the 5 rifles I am loading for.

Today we were testing our 3- 7mm-08's. I am loading a 120 grain Ballistic Tip, CCI BR primer with Varget. At 45 grains, I'm getting slight ejector marks on my Lapua brass (loaded At 2.1920 CBTO) as well as my son's Nosler brass (loaded to 2.2120 CBTO). I did not have any hard bolt lift.

How much should I drop charge? Is .5 grain appropriate? More? Less? Worst part is my best group came at 45 grains. Oh well, I'd rather be safe than sorry. It was 35 degrees today. Which is approximately our hunting conditions of 0-50 degrees.

Thanks all.
Steve

 

[GLTaylor]

Are you cratering primers or noting gas leakage around your primers? "Slight" ejector marks is subjective. If you are seeing any ejector marks, you are shortening brass life and seeing higher pressure. Also, at warmer temps you will likely increase pressure substantially. Your call. See if .5 reduction stops ejector marks.

 

[BoomFlop]

Primers are a little flat. No cratering of primers, all perfectly smooth. Ejector mark can only be noticed in the right light and no swipe.

I want to be safe first and foremost.

Steve

 

[26Reload]

Last year someone else was showing pressure signs in cold weather shooting...have a looksee...

 

[antelopedundee]

Primers are a little flat. No cratering of primers, all perfectly smooth. Ejector mark can only be noticed in the right light and no swipe.

I want to be safe first and foremost.

Steve

I don't think I'd worry about it in a hunting round as it seems to be maybe top load. I'd keep any cases like that as a separate lot from the others. Cool a couple down in the freezer and see what happens. Reduce your load and see if accuracy suffers.

 

[BoomFlop]

As I worked up, I didn't have any of these marks on 44.5 in either gun. In fact, I missed the marks at the range. It wasn't until I was home and turned a case just right in the light that I seen it.

Accuracy in my Remington Mountain rifle was best at 45 grains, however, I don't want to push the envelop so to speak either.

I'm guessing I am seeing pressure at Nosler max with Lapua and shorter CBTO, which was determined by seating depth test. My son is loaded longer but Nosler brass from my understanding is pretty soft.

Please advise - what would you do?
Steve

 

[GLTaylor]

If the ejector mark is that light and no primer cratering and no primer deformation, I'd say go with it for hunting. Just remember pressure will rise with temp.

 

[BoomFlop]

By primer deformation, do you mean flattening? I have flattening, but no cratering.

 

[sedancowboy]

Steve your loads are ok. A rough ejector tip or any number of things could be causing a slight ejector swipe. Nosler brass is soft and almost all loads i have seen with Nosler brass has some swipe marks. For hunting loads you will be fine. Remember not to shoot your hunting loads when it is 100F next summer.
Henry

 

[243winxb]

7mm-08's, running at 61,000 PSI may produce some light ejector marks firing factory ammo. A wet chamber & extra head clearance may cause it to appear sooner.

Keep brass separated for each rifle. link to photos

 

[BoomFlop]

I tried to take the best pictures I could. I put the marks at the 3 o'clock position for reference.

Lapau top case is on "em" and the bottom case is on "7m"

Nosler top case is on "7-0" and the bottom case is on the "L".

I want to be safe, I don't want to ruin my brass way early (they are hunting rifles that are not shot a lot) but at the same time I don't want them to be "slow" either.

I have read I should reduce 5%? What do you guys do when you get an ejector mark on a case with 45 gr?

Thanks
Steve

 

[LVJ76]

Hey Steve, like @GLTaylor mentioned, back off 0.5gr and play it safe. Varget is not really temp sensitive but your brass will still thank you.

0.5gr won't kill you on velocity or terminal performance, the whitetail still won't know what hit him or at what speed.

I do envy your 30 degrees, it was 88 today and it seems it will still be hot in two weeks when we go after coues.

Stay safe brother and happy hunting.

 

[jebel]

I agree with backing off about 0.5 grain and then +/- 0.1 or so if it helps with accuracy. You are likely fine at 45.0, but loads closer to the edge must be watched more closely and brass likely will suffer.

Even if you had to drop further to get accuracy where you want it, I suspect you'd still be at a velocity that allows you to do everything you want.

 

[Deleted member 115654]

Primers DMS. Hornady Outfitter ammo has rounded primers (like Winchester). When they come out of my 300 WinMag the radius is flat. Runs thru the Chrono at what the box says, shoots 1/2 moa and cases fall out of my Blaser which no 98 Mauser when it comes to extraction.

Absent a pressure transducer, "pressure signs" are a best guess.

A Chrono and reloading data matched to your powder and bullet exactly will keep you safe. (As has been said here too many times to count)

No Elk ever died faster due to an extra 100 fps.