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  1. D

    I'll Post This Here - Hornady's Podcast #50. I thought it was one of their best, but some reloaders might not like what they see....

    Extreme Spread can only increase with group size. If you think that there is some absolute upper bound on shot dispersion then you could bound the sample distribution so that you never see an extreme spread beyond that, but even then the average spread for a given number of shots would only...
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    I'll Post This Here - Hornady's Podcast #50. I thought it was one of their best, but some reloaders might not like what they see....

    Real math and statistics for this has all been worked out in detail on Ballistipedia, with significant improvements over what Grubbs was able to do 60 years ago.
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    Adjustable butt pad (for MRAD)

    I really want an AI AX-style adjustable butt pad on this MRAD, like the part highlighted here: (I.e., at least vertical adjustment; ideally adjustable for cant as well.) The MRAD butt plate, shown attached, is tapped for two machine screws 5" on center. So if I could find something like this I...
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    Range Report What is the purpose of the tail on Lapua's Lock Base bullets?

    Ah ha: So the LB was likely created to provide better accuracy (under broader loads) than the D46 while still satisfying conservative legal interpretations of the Hague Conventions. Before considering that I was also wondering if the closed tip might offer the benefit of a consistent point vs...
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    Rifle ergonomics

    I'm trying to figure out how well I should expect my rifle to fit me. I have a lanky build, and I've shot a number of different stocks with various degrees of adjustment and never found one that lets me get my head positioned so that I don't have to cant it severely to get my dominant eye...
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    Range Report Federal dumping light loads of .308 FGMM?

    I've been wondering why .308 FGMM has been showing up under $1/round recently. I bought some 168gr and pulled a round and found it only had 40.3gr of powder, which IIRC is light for them. I chronographed the box at 2645fps from a 22" bbl. IIRC we could expect more like 2730fps out of 22" with...
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    Where would demil 220gr .30" OTFB bullets come from?

    Would make sense, except it's the same length as a 220gr SMK (see photo here). I do believe it's from a subsonic 300BLK run: Seating to the cannelure results in COAL of about 2.15", which was Remington's preferred subsonic length. Still curious what possible advantage the flat base provides....
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    Where would demil 220gr .30" OTFB bullets come from?

    Ah ha: Good finds! I don't doubt that for subsonics the flat base doesn't hurt ballistics significantly, but it doesn't help, and it's still an open-tip bullet. Is it so much more expensive to put a boat-tail on such a bullet that it could be cheaper to produce flat bases (even given that the...
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    Where would demil 220gr .30" OTFB bullets come from?

    I've gotten some interesting demil'ed bullets from American Reloading, but they can never tell me their origins. I've been using 220gr OTFB bullets (attached) for subsonics and (not surprisingly) they're just as accurate as premium BTHP pills. But I can't figure out what mil-spec cartridge...
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    Range Report What is the purpose of the tail on Lapua's Lock Base bullets?

    I just pulled a factory Lapua .338LM 250gr Lock Base and had never seen a bullet with this ... sprue? ... in the base before. What is the purpose of this design? My best guess is that it's like an open-tip in reverse – i.e., the jacket is drawn from the tip to the tail. So it saves the trouble...
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    RL-17 and RL-19 for 225gr .339LM

    I can't find any reference loads using RL-17 or RL-19 for 225gr bullets in .338LM. QuickLOAD suggests that any slower Reloder powders won't fully burn out of a 25" barrel. So is QuickLOAD way off here? Or is there some other good reason these faster powders aren't listed with lighter bullets...
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    Night Vision Why do NVDs mount in front of scopes?

    I can't understand why all of the common NVDs mount in front of the standard "daytime" rifle scopes: Doesn't this require extra optics to focus the image on the intensifier and then back it out to the original focal distance so the day scope can make use of it? Why wouldn't it be simpler and...
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    Labradar doppler chronograph

    Ah ha, I knew there had to be something! Human ingenuity to the rescue: first the invention of gunpowder, then movable type, and now e-readers! Of course it's asking a lot of someone in this day and age to take a handwritten manuscript and pay not only to typeset it but also to somehow...
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    Labradar doppler chronograph

    If only there were some way to ship information cheaply without printing bound paper copies and physically transporting those copies around the world.... ;)
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    Range Report Boat-tail backward ballistics

    Homemade subsonic hollowpoints Knew I had tried this: Here's a 240gr SMK drilled out and fired subsonic into a Fackler box. Fragments broke off but only down to the drilled depth.
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    Range Report Boat-tail backward ballistics

    Wow. Stop teasing! Where's a copy?
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    Range Report Boat-tail backward ballistics

    Do you have any photos post expansion? I noticed your paper said of back-drilled Partitions: I tried drilling bullets for this purpose some time ago and testing them in a water tank: They would essentially shed fragments to the drill point and otherwise stay intact. I couldn't get any sort...
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    Range Report Boat-tail backward ballistics

    Yeah, there are a few pricey options like Lehigh Defense and Outlaw State. The Lapua 200gr subsonic bullets are (supposedly) optimized for external ballistics and accuracy. They absolutely will not expand.
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    Range Report Boat-tail backward ballistics

    No traditional rifle bullets currently available expand subsonic. (Looking forward to Norma importing their Plastic Points next year!) From what I've tested nose first tends to upset faster. The reason I've been playing with them backwards is that they have an uncanny ability to "swim"...
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    Range Report Boat-tail backward ballistics

    Is anyone aware of exterior ballistics data or coefficients on boat-tail bullets fired backwards (i.e., base first)?