Tuesday, December 14, 2010

"Shoots flat!"

I've owned a couple of Glock 33's in my time, which is Glock's itty-bitty subcompact in .357SIG. They were a hoot to shoot: Lots of flashenbangy with target ammo and they'd throw the brass into the next county.

Like half the .357SIG shooters on the internet, I'd crow about how "flat-shooting" the round was...

...which, in retrospect, made me look a little dumb.

See, at the time, I did almost all my shooting at an indoor range, and at seven yards, all pistol bullets shoot flat. At 21 feet, there just is not one lick of difference in trajectory between any two handgun rounds. At 25 yards, there's hardly any, and even 'way out at a hundred, beyond where most people will ever shoot a handgun, there's only about 7 or 8 inches of difference between the trajectories of a lumbering 230gr .45ACP and a zippy 125gr .357 Magnum.

This is because trajectory is mostly affected by speed¹. Bullets start falling at 32ft/sec² the instant they leave the barrel; the faster they're going, the more ground they'll cover before they fall. And pretty much all handgun rounds are travelling about the same speed, which is "slow", at least compared to rifle rounds. Seriously. There is a larger velocity spread between the slowest and fastest commercial .30-'06 loads than there is between a "slow" handgun round and a "fast" one², and the "lumbering, rainbow-trajectoried" .45-70 will outrun your "zippy" 5.7x28 wonderpellet.

Differences in handgun velocities and the resultant trajectories might be important if you're trying to whack a coyote at 100+ yards in a soybean field, but if you're only shooting at 7 yards at the indoor range, don't pop off a magazine and then turn to your buddy and natter about how "flat shooting" your favorite heater is, okay? It's like walking up to a painting and saying "Hmmm... Interesting use of negative space!" or swirling a mouthful of wine around and saying "Pretentious, yet understated!"; it makes you look kinda goofy.

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¹ And velocity is affected by ballistic coefficient, and... but that's a whole 'nother kettle of fish.

²The velocity spread between a "slow" handgun bullet at ~900fps and a "fast" one at ~1400fps is less than the difference between a 125gr .30-'06 at 3100fps and a 220gr .30-'06 at 2400fps.

30 comments:

  1. It's like walking up to a painting and saying "Hmmm... Interesting use of negative space!" or swirling a mouthful of wine around and saying "Pretentious, yet understated!"; it makes you look kinda goofy.

    I see you've been to the 4th floor of the IMA...oh, and my 'Geography of Wine' class!

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  2. But I like looking goofy. I thought that was understood by nigh all and sundry?

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  3. Speaking as one who DOES regularly try to whack coyotes and other things at 100+ yards in soybean fields, I reiterate my position that projectile trajectory IS important, but as you explain it is a function of velocity (1,200 fps+) AND the ballistic coefficient of the projectile.

    One of my objections to the .45 ACP is I was never able to whack anything with it in the field more than 100 yards away; especially after the first shot when they started MOVING.

    Thus my innate devotion to all things .41 Mag and 10mm Auto...

    All The Best,
    Frank W. James

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  4. Frank,

    "One of my objections to the .45 ACP is I was never able to whack anything with it in the field more than 100 yards away..."

    Did you think I pulled the soybean field thing at random? ;)

    True, out around 100 yards, seven inches is the difference between over a coyote and under it; magnum calibers make a ton of sense when trying to snap shoot targets with a handgun at that range.

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  5. Regarding footnote the second -- you should be using the ratio for comparison, not the "spread". Think it through at the extreme of your argument, in this case a thrown baseball.

    When making an engineering argument, subtraction is almost always the wrong operation.

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  6. Hypnagogue,

    None of which changes the fact that I'll bet:

    A) 90% of handgun shooters will ever shoot their handguns far enough to observe any meaningful difference in "trajectory", and...

    B) Whether we want to use ratio, spread, or inverse Hungarian algebraic notation, the difference in drop between a slow pistol bullet and a fast one is at any range out to 100 yards is completely negligible when compared to the difference in trajectory between a slow rifle bullet and a fast one at 300. We can leave the different weights of .30-'06 alone and compare, say .45-70 to .22-250, if we wanted to get extreme about it. :)

    As Farmer Frank pointed out, if you want to hit small, fast-moving targets beyond 100 yards, then trajectory matters. This is why I own things like .41 Magnums and .22 Rem Jets.

    This is not, however, a scenario oft encountered at the local indoor range or in real CCW use.

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  7. As long as we're talking math, it should be noted that the benefit of a flat-shooting round is directly proportional to the marksmanship skill of the shooter. For some people, 7" at 100yd is less than their wobble radius and therefore makes little to no difference. On the other hand, when you're trying to whack plates at 100yd+ it's really nice when you can maintain a consistent sight picture rather than trying to account for distance with kentucky windage.

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  8. ... or swirling a mouthful of wine around and saying "Pretentious, yet understated!"

    What I especially like about .357SIG is the subtle notes of cherry and tobacco on the finish ...

    ;-)

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  9. ToddG,

    "On the other hand, when you're trying to whack plates at 100yd+ it's really nice when you can maintain a consistent sight picture rather than trying to account for distance with kentucky windage."

    Harder to estimate holdover with that big, black HK45 slide in the way, eh? ;)

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  10. I had a Glock 33 once.

    I had to sell the thing when I couldn't find ammo for it anywhere in Northern Minnesota.

    In retrospect I should have just converted it over to .40 S&W but I was young and didn't.

    Traded it for a steyr instead.

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  11. Tam said: "Harder to estimate holdover with that big, black HK45 slide in the way, eh? ;)"

    Oy vey! On the other hand, after a day at the range it makes for a very convenient picnic table.

    In all seriousness, though, it does point out the contrast. Years ago I took a class that included a walkback drill on a steel target. At 130+ yards I was still shooting POA/POI with a P229 in 357 SIG and won the contest. The last contender was shooting a Govt Model and while he had the benefits of a far better trigger and longer sight radius, eventually his trigonometry skills are what cost him the win.

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  12. This is precisely why I don't have any interest in the last decade or more of mini-maxi-magnumitis that has befallen the rifle world.

    I've been quite happy with the performance of cartridges that were designed in the middle twentieth century or before, and I will continue to use these until I see something that is truly an improvement on what I know works, and see the supply line keep up with that improvement for at least ten years or more.

    The .357 Sig, for example, just doesn't qualify by those standards (for me), as I just don't see the advantage that it has on, say, +P loadings of 9mm.

    Again, if we are looking at rifle cartridges, my .308 looks really good compared to the latest WinWonderSuperShortUltra-Whatever caliber for taking out Bambi. Range isn't much of a consideration for the typical hunting scenario, and most people who think they need to step up to a Magnum of any sort usually tell you that they need, "more power," for taking down something bigger than your average whitetail. What they need in that case, as Col. Cooper explained many years ago, is more bullet, not more powder, and they usually need it on an order of magnitude higher than they think they need. Going from a .30 in 150 grains to 165 isn't buying any more takedown ability, nor would be the case be by stepping up to 180 grains, since the diameter and relative velocities are the same.

    What is clear, at that point, is that moving up to something in the .35 to .375 range, and 250 grains or more is something that is necessary for better performance on large critters, in which case I'll take a .35 Whelen or .375 H&H or any of the 9.3 European pills for taking elk or hogs or whatever.

    Jeezis, you'd think that everyone would know this stuff.

    Still, whatever floats yer boat...by all means, have at it.

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  13. You want flatter, try the 9x25 Dillon (Glock 20 in 10mm is convertible). This only barely approaches a rifle velocity (about 1950fps with a 95gr 9mm projectile).

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  14. JB,

    Begs the question here, why, so the comp guns that it is chambered for can more easily utilize the excessive gas to cut recoil?

    I suppose this makes some sense for those who engage in competitive shooting in the upper echelon of the sport, but, seriously...who cares?

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  15. JB,

    I've known about the 9x25 Dillon for a long time.

    I'd like to think I'm part of the reason why Mike McNett started loading 9x25 Dillon...


    irritablearchitect,

    "I suppose this makes some sense for those who engage in competitive shooting in the upper echelon of the sport..."

    Actually, Leatham tried out the 9x25 back in the day, but it was giving him tennis elbow.

    That volume of gas drives a comp really swell, but I'd rather not have an orthopedic surgeon on speed-dial just to potentially shave a few hundredths off my splits... ;)

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  16. I've shot our 200-yard gong a few times with the '43 Colt and I was a bit surprised at how much I did not have to incline the elevation of the front blade, maybe not as much as the .2WRF model 90 of my wife's. I wasn't in the mortar-platoon in other words.

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  17. ToddG speaks true.

    It's why I have 3" tall Creedmoor rear sights on my 32" .45-70 Sharps Business Rifle. You may have to call ahead for a reservation on a given venison meal or steel buffalo silhouette way out there, but 535gr of lead still speaks with authority. To paraphrase, "Fear not the range tables, but the holes they make..."

    I discovered you can reliably connect to 300 meter gongs with a Bo-Mar sighted .45 ACP 1911 by using the notches on the front sight as a forward vernier. Sure, the .357 Desert Eagle made it easier, but where's the fun in that?

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  18. It's like walking up to a painting and saying "Hmmm... Interesting use of negative space!"

    But... some paintings really do use negative space interestingly!

    That'll teach me to take fine arts classes, I know...

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  19. It's close enough for the current context but a speeding bullet doesn't actually drop at the same rate as a bullet dropped from your hand. There is a component of the horizontal velocity that causes it to reach terminal velocity in the vertical direction more quickly than if merely dropped. Hence the fired bullet will drop a bit more slowly. Look at the range tables with time of flight and drop on them then do the math.

    That nit-picking engineer moment aside... you describe a feature of newbies in almost any field that my friend Ry has termed, "Enthusiastically stupid."

    While I endorse the use of this phrase it isn't really quite fair. Given enough time these people mature and become tolerable enough for association in polite company. If they were truly stupid maturity would only cause them to grow more quiet rather than smarten up.

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  20. Joe,

    "It's close enough for the current context but a speeding bullet doesn't actually drop at the same rate as a bullet dropped from your hand."

    I know that, but for pistol bullets at <100yds, I figured it was immaterial, and there was no need to go to Ballistics 202... ;)

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  21. Eric Timrud and I were shooting 200 yard highpower once, a few decades ago, down at Blue Trail Range in Wallingford.

    They had a chunk of boilerplate about 20 inches wide and 30 inches long dangling from two chains at 150 yards.

    We took Eric's creampuff 1950's Colt 1911, took turns stretching out in prone with the butt on the ground, and learned that holding one third of the front sight over the rear gave consistent 6 to 8 inch groups at point of aim.

    Admittedly, an exceptional pistol, two good shots just home from working for Uncle, and Eric's very fussy handloads (6.5 gr. Unique/Lyman 225gr. roundnose).

    But, again, from a rest, I've gone 5 straight on bowling pins at 100 yards (the trick is to hold a tad below the bottom, as, if you miss, you get a second chance with the ricochet and various clods thrown up).

    I'm suprised someone doesn't have 100 yard prone unsupported pistol as a viable target event. I can actually see it as a useful extra for law enforcement.

    If some cop out in Wyoming or Utah found himself seperated from the rifle in his cruiser and under attack by a dingleberry with a 94 Winchester, he might well be able to discourage the perp, while also presenting a minimal target.

    But only if he practiced enough to "git'er done".

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  22. Tam,
    Flat shooting pilots.
    https://mail.google.com/mail/?ui=2&ik=1932454130&view=att&th=12ce721fa94370e3&attid=0.1&disp=attd&zw

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  23. This is partially why FrankenGun is a 10mm, and a large reason why SpaceGun follows the same path.

    If I'm having trouble with 165gr (I think? haven't seen them in a while) doubletap 10mm making the grade at distance out of the big pistol, then all I need to do is drop the mag and clear, then insert same mag and ammo into SpaceGun and enjoy a more stable platform, "better" trigger (FG is a Para LDA while SG has a standard 1911 FCG), and a reflex sight.

    If I recall correctly that ammo is rated for ~1400fps at the muzzle with a roughly 5" barrel... 16.5" should give me around 200 more, you think? And they have a 135gr load with 1600 at the muzzle as well.

    And if that doesn't do it, the carbine should push their 230gr WFN hard-casts at 1300-1400 or so, if they'll feed.

    Of course, ballistic coefficient bites me in the ass on those so range isn't anywhere near the two stats would seem to support. But who cares, I have a 20 round double-stack 1911-triggered short carbine with a frickin' laser (ok, LED sight) beam on it's head, AND a matching pistol! Yeehaw :)

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  24. There's a madman who ran amok at the Fairchild AFB base clinic in 1994 who was dropped by an E-4 SP with two out of four rounds from issued M9 (USGI Beretta 92) at 70 yards. Him what died of lead poisoning upside the head was also slinging a MAK-90 at the time, killing 5 people before aforementioned SP ended his time on earth. Probably the exception rather than the rule, but one can't say it never happens...

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  25. G98,

    I was wondering when that particular Ayoob File was going to make its appearance. I thought about mentioning it as an aside in the initial post, but I trust my commenters. :)

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  26. Truthfully, I never thought of it as an Ayoob File, Tam. The story stays fresh in my mind because I was attached to the 92nd Bomb Wing, flying modified B-52H Giant Fish variants out of Fairchild AFB at the time. I'd actually used the flight surgeon at that base hospital when I had a squeaker of a sinus infection - he got the privilege of both grounding me and releasing me for flight duty. The MAK-90 gunman incident really messed up the SrA SP, who wasn't allowed to seek counseling without turning in his badge and gun. He later sought and received a medical discharge. "Here, have a limited-edition, highly-coveted Airman's Medal, but we ain't gonna help you with the aftermath..."

    All of which I found disheartening, considering that the SERE instructors down the street at Fairchild AFB who delighted in tormenting me at both Combat Survival and Advanced Beatings all had regularly-scheduled psych evals as part of their duties.

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  27. G98,

    Ouch.

    That's an unpleasant postscript to the story. :(

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  28. I, myself, have travelled faster through the air than the bullets emitted from either of my hand-pieces, assuming standard generic loads.

    It was in a Delta Convair 880 back around 1969. It was the best airline trip I ever had; the airplane was mostly empty, and I had a good conversation with the stewardess.

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  29. Hah! I saw that "inverse Hungarian algebraic notation." You wouldn't happen to have an old HP calculator lying about, would you? I have an HP-11c with a busted display, and an HP-12c which I bought recently, and am disappointed to find that it was built in the Middle Kingdom.

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  30. Oh, Joe! You mean the bullet gets a bit of lift from passing through the air?

    WV: awismal. Is that worse than abysmal?

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