Washington's Birthday CHOKE!

204-1x out of 300.

[hangs head in shame]

That's 68%, whereas my last two matches have been 80%.

I think I got bit by a lack of environmental knowledge.  We went directly from standing to rapid prone with no sighters.  I was shooting low, by about 3-4 MOA.  Part-way through my rapid prone my spotter team-mate told me I was hitting low.  I adjusted hold from 6-o'clock on target to center of target for 3MOA increase.  That moved me from the 5/6 ring area to the 7 ring.  I dropped off-target with 1 shot, scoring 1 miss.  Part way through that string the sun peaked out.  "Lights up, sights up!"  When the light gets significantly brighter, you tend to drop your shots 2 MOA on target.  So, my 3MOA sight hold adjustment got mostly negated by the increase in light.

So, I now know I lose about 3-4 MOA when going from standing to prone.

And I'll remember to compensate for increased light (or a decrease in light by dropping my sights 2MOA when the sun is obscured by a cloud).

Not happy with that score.  But, there's always next year.

Who Says Nickel-Plated Brass Isn't Any Good?

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.