light ejector marks but good groups

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VinceMarksman

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My new load with SMK 175g looks to be settled at 45g of varget in lapua case with a 0.020 jump. During my OCW test 45g was the one that grouped the best and POI seemed about right with surrounding loads. I tested 44.8 in 5 shot groups and had a flyer each time.

I shot 2 x 5 shot groups today and group size was .75 MOA and .5 MOA. There was moderate mirage and I was shooting with my new chassis, one group from the mag and one group single loaded. The group from the mag was the biggest one.

With that 45g load im getting very slith ejector marks but no crater and no hard bolt lift. Should I keep this load despite the ejector marks? Im guessing it will have a nice speed on the chrono...
 
VinceMarksman said:
My new load with SMK 175g looks to be settled at 45g of varget in lapua case with a 0.020 jump. During my OCW test 45g was the one that grouped the best and POI seemed about right with surrounding loads. I tested 44.8 in 5 shot groups and had a flyer each time.

I shot 2 x 5 shot groups today and group size was .75 MOA and .5 MOA. There was moderate mirage and I was shooting with my new chassis, one group from the mag and one group single loaded. The group from the mag was the biggest one.

With that 45g load im getting very slith ejector marks but no crater and no hard bolt lift. Should I keep this load despite the ejector marks? Im guessing it will have a nice speed on the chrono...
Click to expand...

If your ejector mark is a raised bump it means the chamber pressure is to high and you have brass flow into the ejector.

If you just have a circular ring you might have sharp edges around the ejector hole in the bolt face. And stoning and polishing the the edges of the hole with fix the problem.

Below is a raised bump caused by high pressure, and the raised bump varies with brass hardness between manufactures. And it also means your primer pockets are expanding and you will have oversized loose primer pockets.

KtO65uH.jpg


How Hard is Your Brass? 5.56 and .223 Rem Base Hardness Tests
http://bulletin.accurateshooter.com/2014/05/how-hard-is-your-brass-5-56-and-223-rem-base-hardness-tests/

Simple Trick for Monitoring Pressure of Your Rifle Reloads
http://www.hodgdonreloading.com/reloading-education/tips-and-tricks/simple-trick-monitoring-pressure-your-rifle-reloads

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I've spent a lot of time talking myself into believing that ejector marks weren't a sign that Id already gone to far because so many loads shoot well at the red-
line . It helps that I a have the the gift of being at once convincing and gullible; but eventually the truth wont be denied.
 
Dogleg said:
I've spent a lot of time talking myself into believing that ejector marks weren't a sign that Id already gone to far because so many loads shoot well at the red-
line . It helps that I a have the the gift of being at once convincing and gullible; but eventually the truth wont be denied.
Click to expand...


That is the absolute truth, many times the best groups and lowest ES come right at the ejector mark level.................that's why I bought Henry Remple's primer pocket shrinker.......onward and upward now !!!!
 
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