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atyszka
11-19-2012, 21:44
Was at the range today testing some loads I'm working on and found these 2 cases early on. There were no others, but it's not that hot of a round so I'm surprised and wondering if anyone else has seen this. I wouldn't be concerned if this was the 3rd time for this brass, but they're brand new.

New Starline brass
Stock G20
50F, 81% Humidity, 902 ft elevation
165 gr GDHP
15.6 gr AA #9
CCI 350
1311 avg fps
1.255 OAL

No other pressure signs (other than slightly flat primers which is always the case for me), case head is only .433

Thanks

_The_Shadow
11-19-2012, 22:00
That happens sometimes, brass may have been brittle in that area and as it stretched it split. Usually Star Line is soft and rarel splits like that, however I have seen many factory loads split their cases on the initial firing! Better case support can also help as the stock Glock chambers are loose.
Good luck!

Yondering
11-19-2012, 22:33
I agree with Shadow. Weird that it happened with new Starline brass, but with that load, I think you just got some bad brass. I've run into batches of Winchester and Lake City 5.56 brass that do that in factory ammo; sometimes it just happens.

WeeWilly
11-19-2012, 23:13
I have had an occasional split on new Starline with my G20/29 loads. I think if you are getting more than a couple in a batch of hundreds, I would contact Starline and see what they think. I think my failure rate might be like 1-2 every few thousand.

atyszka
11-20-2012, 06:17
Thanks for the insight guys. I've loaded tens of thousands of .40 and only see this on cases that I've shot 3-4 times. So I was surprised when it happened to a new case. I'll watch and if anymore pop up with mild loads I'll contact Starline. I ordered 1500 new and have shot about 700, so almost half way through the batch.

SDGlock23
11-20-2012, 09:00
I had the same thing happen with some Top Brass I had at one time, lots of splitting going on.

OregonG20
11-21-2012, 13:58
Was at the range today testing some loads I'm working on and found these 2 cases early on. There were no others, but it's not that hot of a round so I'm surprised and wondering if anyone else has seen this. I wouldn't be concerned if this was the 3rd time for this brass, but they're brand new.

New Starline brass
Stock G20
50F, 81% Humidity, 902 ft elevation
165 gr GDHP
15.6 gr AA #9
CCI 350
1311 avg fps
1.255 OAL

No other pressure signs (other than slightly flat primers which is always the case for me), case head is only .433

Thanks

I've had new Starline do the same to me with 155gr and 180gr XTP's. CCI300, 1.26 COAL and close to book max charges of AA #9 as well. No other signs of pressure. No problems either.
I think it just happens with Starline brass sometimes. Hasn't stopped me from shooting or changing my loads. YMMV.

Taterhead
11-21-2012, 21:06
The charge is certainly not a mild load. It is a tad over book max, but the brass is the culprit. Sometimes they are not properly annealed from the factory. It happens. Vertical splits in the middle of the case are not terribly problematic. Horizontal ones near the head are a different story.

A small handful out of a box of a thousand will do that in my experience.

AstraPat
11-22-2012, 10:11
Brass issue for sure. I would suspect the annealing process wasn't properly completed

P

Kwesi
11-22-2012, 10:35
It happens to my 10mm Starline brass after numerous loadings. My nickel seem to last longer compared to regular brass.