So, previously in January I wrote about a need for new brass. I ended up ordering 500pcs of Remington nickel-plated new brass.
I went out Sunday morning to test my loads.
Load:
New Remington nickel-plated brass
168gr Hornady A-Max bullet
CCI #34 primer
IMR 4895 powder
2.790 OAL
Lee FCD, moderate crimp
Case trim length: 1.990
I found a LOT of case weight variation. 164.0 to 167.5. I'm not certain if that's because it's Remington brass rather than something with a higher reputation for consistency (Nosler, Norma, etc) or due to the nickel plating that could introduce greater variation. I grouped the cases into similar-weighted (+/- 0.2gr from a center standard) lots of 5 for each powder charge below:
Powder charges:
5 rounds 39.5gr
5 rounds 40.0gr
5 rounds 40.5gr
5 rounds 41.0gr
5 rounds 41.5gr
I did confirm the weight of each powder charge, though I allowed for a variance of +/- 0.1gr rather than trickling for a perfect target weight.
I didn't weigh the bullets.
Discard farthest "flier" from each 5 round group. All fliers were called as sight picture was brought into question. Measure group with 4 best confident shots. Shooting position was improvised prone rest on top of range bag and padding. Target was 100 yards. Groups measured with a tape measure since I'm too lazy to go hunt down my micrometer right now.
39.5 group: 1.875"
40.0 group: 2.375"
40.5 group: 1.125"
41.0 group: 0.5"
41.5 group: 1.625"
Pretty clear what it likes. I've never found a sub-MOA group before. Nifty. I've never shot a sub-MOA group before, even with a scoped rifle. Yeah, it was from an improvised field rest, but it still wasn't some stupid caldwell lead sled from a concrete bench.
And... did I mention I trimmed all my new brass for this load development (25 pieces) in about 4 minutes? I love my new Giraud trimmer.
I'm happy with the nickel-plated brass. It's not nicked/dinged on extraction so far, whereas new brass will pick up a nice gouge on the side of the case as the extractor flings the case against the front of the op-rod. These cases are tough enough to escape unscathed. Extraction groove on the case also has no visible deformity, whereas a typical Federal brass case will have a visible scratch or dent on the rim from even the first firing. After 4 firings, the rim becomes difficult to seat into a reloading shell holder due to the scratches in the extractor groove. We'll see how these hold up over time.
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