loss of faith in Quickload

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mtngun
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loss of faith in Quickload

Postby mtngun » Sun Feb 10, 2008 5:49 pm

from the old forum:

More 3006 traces: 4895, 3031, primer falls out.

This is the usual 180 gr. loverin in the 30-06. Today I tried faster stick powders hoping to make the secondary spike go away.

50.3 gr. H4895, 2.790" COL, 0.314" HTWW, Rooster HVR, Fed #210. My Quickload prediction was 2624 fps at 53 ksi, it was actually 2789 fps and 75 ksi. The second shot "let the smoke out", the bolt had to be hammered open, and the primer fell out of the case. Oooops :oops: Needless to say, that was the end of that test.
Image

Same load except 49.0 IMR 3031. Quickload had predicted 2661 fps at 53 ksi, it actually was 2777 fps at 73 ksi. Oooops :oops: Bolt lift was normal. Primers were slightly flat but not out of the ordinary. The cases do show a faint ejector mark, but I wouldn't have noticed it had not Pressure Trace alerted me to a high pressure condition.
Image

If time allows, I'll double check my Quickload calculations, and post pictures of the cases, and measure case head expansion. In the meantime, we can say that 3031 reduced the secondary spike (compared to Big Game or 4350) but did not eliminate it. I didn't bother measuring groups today, but based on my experiences with these powders in the 7-30 waters, I now doubt that 4895 or 3031 would give decent accuracy with full throttle cast bullet loads.

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mtngun
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Posts: 1633
Joined: Fri Feb 01, 2008 5:45 pm
Location: Where the Salmon joins the Snake

Re: loss of faith in Quickload

Postby mtngun » Sun Feb 10, 2008 5:54 pm

Here's a picture of the cartridges.:cry:
Image

When viewed with a magnifying glass, the 3031/4895 cases show an ejector mark on the head and a tiny bit of protrusion around the firing pin, while the validation case does not. Without magnification, you wouldn't notice a difference. As you can see in the picture, the primers were not severely flattened, not even the primer that fell out.

The case that spit out the primer has partially seperated at the web. It had been reloaded 20 - 30 times previously.

The other 4895/3031 cases have about 0.0015" - 0.0020" expansion at the web, compared to resized cases from the same batch. The validation case has no expansion at the web.

I double checked my Quickload calculations. The loads had been based on a 58 ksi estimate rather than 53 ksi as stated earlier, but otherwise everything checked out. I hate to admit it, but Quickload was very wrong. :o


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