Breathe.
Relax.
Aim.
Squeeze.

There’s no substitute for practice.

I am remiss in pointing out that my undergraduate alma mater, Wake Forest University (#15, 10-2 regular season), won the ACC football championship last weekend and will compete in the Orange Bowl against #5 Louisville. It’ll be a tough fight for either team to win. Louisville has the second-ranked offense in college football, averaging 477 yards and 39 points per game. Wake, on the other hand, allowed fewer than 15 average points per game. The Deacs also forced 21 turnovers in the last eight games of the season and finished the season ranked first in red zone defense. The game will be played at 8 p.m. EST, Jan. 2.

That’s what Mark English says Yankees owner George Steinbrenner has really been saying with all the talk about firing Manager Joe Torre.

Commissioner Bud Selig has put down the curtain on making any clubhouse changes during the playoffs so that fans remain focused on the playoffs. …

Suppose however, [Steinbrenner] was willing to play within the rules. If that is the case, then all this talk about Torre being fired could just be a publicity stunt to limit the coverage of the New York Mets as they prepare to play in the NLCS. Is this so far fetched? Not really. He’s done it before.

In 1988, he fired Lou Piniella (whom ironically could be hired to replace Torre)…and hired Dallas Green shortly before the Mets were set to play in the NLCS against the Dodgers. This set off a media storm which temporarily distracted the press from the Mets, and focused their attention onto the Yankees.

Also, from the Boss’s perspective it makes more sense to keep Torre on for at least one more year, since his contract is up next year anyway. Then next year, Torre can ride off into the sunset, while the Yankees look to move into a new direction.

Either way, the Boss has managed to dominate the back pages, even while his team could not dominate the Detroit Tigers.

And that makes a lot more sense than anything else I’ve heard or read about the Yankees saga. Especially since today Joe Torre announced he would not be leaving the club.

Some really good sports coverage over at Mark’s blog, American Legends.

Truth in posting: I am a secret Yankees fan while always cheering for my number one team, the Atlanta Braves. Alas, neither did much good this season.

Thye topic is baseball. Have you ever seen a double play at home plate? Neither had I until this afternoon. It’s the Mets v. the Dodgers in NLDS game 1.

Sorry, I don’t follow either team so I don’t know players’ names. But what happened is this:

Update: Now that news reports have hit (10/5) I’ve deleted my original text and inserted the Daily News account:

Mets catcher Paul Lo Duca tagged out two runners at home plate on the same play in the second inning of yesterday’s 6-5 series-opening victory at Shea.

“It was a bizarre play and it was a very good sign for us early in the game,” LoDuca said. “It was one of those I’d like to see again, because I’m still not sure exactly what happened.”

Don’t worry, this replay will make its away around highlight reels for years. Jeff Kent and J.D. Drew had opened the top of the second with singles against John Maine. Russell Martin followed with a liner to deep right that caromed off the base of the wall.

Kent had tagged up at second to see if the ball would be caught, and Drew correctly had gone slightly more than halfway up the line between first and second.

Kent said he turned and yelled to Drew “let’s go” when he saw the ball drop, thinking both runners could score. But Green made a perfect throw to relay man Jose Valentin, who wheeled a hurled another strike to Lo Duca.

“I turned and saw Kent tagging and knew we had a chance to get him,” Valentin said. “Then J.D. came in right behind him. I couldn’t believe we got them both.”

After Lo Duca applied the tag to nab the headfirst-sliding Kent, he couldn’t hear Maine, David Wright and Carlos Delgado screaming at him to turn around.

Lo Duca said he was tipped off that another runner was oncoming by the eyes of home-plate umpire John Hirshbeck.

“John didn’t make an emphatic out call on Kent probably because he saw Drew coming, too,” Lo Duca said. “As soon as I spun around, he was right there. Wild play. Huge play.”

Double play at home plate. Now, that’s unusual, to say the least. In fact, the last time it happened was in 1985 “when Yankees’ Bobby Meacham and Dale Berra were tagged out by Carlton Fisk.” When I find it on YouTube I’ll embed it here.

Will NFL player Albert Haynesworth go to jail for this?

By now every pro football fan in America knows that Tennessee Titans player Albert Haynesworth was ejected from the Titans’ thrubbing by the Cowboys Sunday. Haynesworth stomped on the bare forehead of Dallas player Andre Gurode, whose helmet had been knocked off during a play. Gurode suffered cuts on the forehead and below an eye that required 30 stitches.

But, in the sometimes screwy rules of the NFL, he wasn’t ejected for kicking Gurode, which drew only an “unsportsmanlike conduct” call. He was ejected for taking his helmet off on the field of play, a severe no-no in the rulebook. (However, there is a report that he was ejected for too-vigorously protesting the original call to a referee. Rumors abound.)

Yesterday, NFL commissioner Roger Goodell delivered a stomp of his own on Haynesworth: a five-game suspension without pay. That’s three games longer than anyone has been suspended before.

How much will Albert lose in income? Again, reports conflict. Last night on ESPN’s Monday Night Football, an announcer said it would amount to $500,000. But Mickey Spagnola says it will amount to $190,000, still serious coin, to be sure.

Immediately after the game, Titans Coach Jeff Fisher told Dallas Coach Bill Parcells that he was “outraged at what happened” and promised that if the Commissioner didn’t render severe enough punishment, the Titans would. Apparently the League’s smackdown is deemed sufficient. “‘I believe that what the league has done right now is adequate,’ Fisher said” (link).

Nashville Titans fans were not defending Haynesworth; many told WKRN TV (ABC affiliate) that criminal action was justified. “If I did the same thing out on the street,” said one, “I’d be going to jail.”

It wasn’t just some fans who thought that way. During the halftime show of NBC Sports’ Sunday night football game, commentator Chris Collinsworth said that Haynesworth’s deed went beyond mere a rules violation. “This was not a personal foul,” he said, “it was a criminal act.” He added that Haynesworth should have been taken off the field in handcuffs. Spagnola reports further,

Should Gurode file criminal charges with the Nashville police[?] In fact, the suggestion has gone so far the Nashville Police Department already felt compelled to release a statement on the issue:

“In assault situations, an affirmative desire for prosecution and an acknowledgement of cooperation from the victim, in this case Gurode, are preferable before officers and prosecuting attorneys move forward with the development of a case.” …

Now there are some of the Cowboys players who believe what Haynesworth did should be subject to police action. Ferguson responded “definitely” when asked if Gurode should press charges. Cowboys quarterback Drew Bledsoe answered similarly.

Some didn’t want to touch the issue, including Cowboys head coach Bill Parcells, who said he appreciated Tennessee head coach Jeff Fisher’s apology after the game… .

Nashville’s Tennessean newspaper reports that Gurode’s agent says this issue is not closed.

Metro [Nashvile] Police contacted the Dallas Cowboys Monday afternoon to indicate they “stood ready to assist” offensive lineman Andre Gurode if he wanted to pursue criminal charges against Titans defensive tackle Albert Haynesworth.

But through the team Gurode told Nashville police he didn’t want to file a complaint, Metro Police Department spokesman Don Aaron said.

Gurode’s agent, Kennard McGuire, said no such conclusion has been reached, however.

“That decision has not been made,” McGuire said. “I expect it will be in the coming days. I have not had the opportunity to fully speak with Andre and his family.”

I am guessing that the legal action that agent McGuire says is still possible is a civil suit rather than a criminal complaint.

The Titans stunk up the joint Sunday, losing 45-14, their worst loss since coming to Tennessee from Houston, Texas, in 1997, when they were still known as the Oilers. With an 0-4 record and poor morale even team members admit, this incident won’t help.

A longer Youtube segment from the beginning of the play is here.

Yesterday I posted about the fallacies of barrel porting or choke porting to reduce recoil in shotguns. My point was that venting the propellant gases laterally to the outside of the barrel or choke has an insigiificant effect (if any effect at all) on the recoil of the gun, for reasons I delved into in some detail in the post. But basically, I maintained that the great majority of the recoil is caused by the reaction to the movement of the shot pellets down the barrel, not the “rocket” effect of the gases.

An interesting discussion followed by commenters, such as Dusty, who wrote,

Actually, the recoil directly relates to the energy released by the chemical reaction of the powder which creates a massive change in pressure due to the gases it creates, and is not, per se, due to the acceleration of the projectile. It is the expansion of the gases, the release of energy, that are propelling both the projectile and the rifle or shotgun. …

To which I replied,

But all this is empirically testable, yes? Someone who reloads (a lot of high-volume shooters do) just reload a shell with the standard amount of propellant and wad and leave out the shot pellets. Then shoot the round. Anyone really think your shoulder will feel the same imnpact absent the shot load?

Now I found a web site that calculates recoil energy right on the page. It uses grains to measure bullet and propellant weights. A grain equals 0.002285 ounce. (Rifle bullets’ weights are typically stated in grains.)

You enter the weight of the bullet or shot, the muzzle velocity achieved and the weight of the propellant. Let’s take, for example, Winchester 12-ga. Super Target ammo:

Propellant: 3 drams (82 grains),
Shot load: 1-1/8 ounces (492 grains)
Wad weight (est.): 1/4 ounce (109 grains, added to “bullet weight” in the calculator)
Muzzle velocity: 1,200 fps.
Weight of my shotgun: 7 pounds, 12 ounces.

The online calculator yields:

Recoil impulse of 4.65 lbs/sec.,
Recoil velocity of 19.34 fps
Free recoil energy of 45.01 ft/lbs.

I used the same inputs, except entering 0.001 grain as the shot weight (that is, a fully charged blank round, no wad) and the result was drastically lower recoil energy, though not, of course, zero. I also doubled the muzzle velocity to 2,400 fps to account for the fact that the gases could escape much quicker if they didn’t have to push the shot and wad out of the way.

The result:

Recoil impulse of 1.46 lbs/sec.,
Recoil velocity of 6.05 fps
Free recoil energy of 4.40 ft/lbs.

Now, I admit that 2,400 fps muzzle velocity may be too low for this blank round, but I have no idea what an accurate figure would be. So lets quadruple the original “with load” velocity to 4,800 fps instead of merely double it to 2,400. This yields no change in recoil energy. In fact, you can enter any muzzle velocity you want and the results never change. Might there be a problem with this online calculator? I dunno, you try it out and see for yourself. But varying the bullet weight field from decimal fractions to low whole numbers does change the results, so I doubt it’s miscalculating.

Like I said, the effect of the propellant gases on the energy of the recoil is minimal. So venting a small fraction of the gases out of the barrel, especially near the end of the barrel, insignificantly affects recoil, if at all.

And now for something a little different. Very long-term readers know that my sporting hobby is trapshooting. Trap is a shotgun sport in which you fire at clay targets launched on rising trajectories at random angles (within left and right limits). The launcher sits in a shed called the trap house and is 16 yards from the closest firing positions. There are five firing positions altogether to give five times as many possible target presentations than with just one. In a competition, you fire 20 rounds from each firing position. The distances from the launcher range from 16-27 yards, although for any one course of 100 targets the range does not vary. Usually, the clay target flies another 18-20 yards before the shooter fires.

That little intro done, today’s subject is shotgun chokes and barrel porting and why buyers thereof might want to re-acquaint themselves with Sir Isaac Newton.

Chokes form the size (diameter) of the pattern of the shot pellets as they leave the barrel. Almost every shotgun today uses screw-in chokes allowing the shooter to vary the final width of the barrel by significant measures. The closer to the target you are, the wider you want the pattern to be as the shot leaves the barrel. In trapshooting you use a more open choke from the 16-yard line than from the 27-yard line. This is because the pellets spread out as they fly through the air. If the shot pattern is too dispersed at the target, not enough pellets may hit the target to break it.

Standard choke sizes range from full (much constriction) to cylinder (little or no constriction). There are also such things as extra-full and many skeet shooters prefer a choke that actually is wider than the barrel’s bore. All chokes’ constriction is measured two ways. One is by the amount of constriction the choke applies to the width of the barrel - that is, how much does it “choke down” the barrel. A Browning 12-gauge, full choke narrows the barrel by .035 inch. The other way of measuring is by the final, actual diameter of the choke. A Browning full choke has a diameter of .706 inch.

The “gauge” of a shotgun historically has meant the number of lead balls of the bore’s diameter it takes to weigh one pound. A 12-ga. bore meant that 12 lead balls of the bore’s diameter weighed one pound. See here. But in manufacture today, that standard seems somewhat flexible. In Britain the 12-ga. gun has a bore diameter of .725. American guns generally are wider. Remington’s 12-ga. bores are .727 inch wide. As for Browning, I’ve seen references that place it from .741 to .745 inch. A Browning web page on the benefits of backboring (increasing the bore width at least part of the way) indicates a bore width of .745. Here’s a good introductory article called, “Choosing The Right Choke For Your Shotgun.”

For my birthday my brother gave me a new Comp-n-Choke brand choke tube in .030 constriction. My new Browning BPS Trap gun came with Browning’s own full (.035) and improved-modified (.025) chokes. While I practice with the full choke from the 16-yard line, I compete using the IM choke. But at mid-ranges such as 20-24 yards, .035 is still too tight and the IM is too loose. Enter the .030.

The new choke is the first I’ve had that is ported. Now, fads infect firearms sports just as they do fashion or education, and for the past three or four years barrel porting has been a fad. “Porting” refers to small holes or slots cut into the sides of a barrel, near the end, for the claimed benefits of less pellet deformity and recoil reduction. Barrel porting is just baloney (but choke porting is not, keep reading), but you see a lot of ported barrels on the ranges today. For a long time, you had to send your gun off to a smith to get it ported, but when gunmakers saw that people will buy anything, they wised up and started factory porting their guns and charging a premium for it.

Like makers of ported barrels, Comp-n-Choke claims its ported choke,

Significantly reduces recoil
The tube design of the Comp-N-Choke allows gases to vent through slots creating a braking system which reduces recoil.

This is how you sell things to people who never studied science. The movement of the shot down the barrel of the gun is governed by Newton’s Second Law.

The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.

In other words, the acceleration that a shotgun shell’s powder load can attain decreases as the quantity of the pellets increases. It’s harder to move greater weights than lesser, using the same energy. As well, increasing the energy increases the acceleration of a given mass. The acceleration of 1 ounce of shot will be greater using 3 drams of powder than of 1-1/8 ounces of shot using the same 3 drams. Force, as we all know, equals mass times acceleration.

This is all common sense, of course, but it’s amazing how many shooters don’t consider Newton’s Second Law when laying out cash for barrel porting.

The whole sales pitch of barrel porting relies on the falsehood that it is the rocket action of the propellant gases that causes recoil. Hence, if you vent them outside the barrel a few inches from the muzzle, recoil is lessened. This is not true, and the reason results not only from the Second Law but from the Third: “For every action, there is an equal and opposite reaction.” And that “equal and opposite reaction” is felt as recoil. With the shot leaving the barrel at say, 1,200 feet per second, the butt of the stock smacks your shoulder at an enormously lower velocity (thankfully!). The reason is, of course, that the shot weighs 1 to 1-1/8 ounce while the gun weighs about eight pounds. As mass increases, acceleration decreases, so eight pounds accelerates a lot less from 3 drams of powder than 1-1/8 ounces.

And that reveals the other part of the fallacy of the porting sales pitch: the recoil does not come from the minimal mass of the propellant gases, which cannot possibly weigh more than the three drams of powder fired to begin with. A dram, BTW, is 1/16 of an ounce in the US, except for apothecary purposes where it is 1/8th ounce. So you have, at most, 3/16th of an ounce of propellant gases and six times that mass of lead rushing down the barrel, and the porting sellers want you to think that the recoil can be reduced by venting a tiny amount of gas near the end of the barrel. Remember, F=(M)(A): it’s the shot’s acceleration that causes the recoil, not the gas’s. The gas alone does not have enough mass to much accelerate eight pounds of gun. And not all the powder is converted to gas anyway. In fact, most is not and is ejected from the barrel unburned or left as residue inside the barrel. I’m no expert of burn dynamics of small-arms propellant, but I’d guess that a burn ratio of one-third would be outstanding.

So much for the claimed recoil-reducing effects of barrel or choke porting. In fact, that claim for choke porting is even more absurd than for barrel porting because the choke is at the very end of the barrel. By the time the gases reach there all their net effect of recoil has already been accomplished, the same for the shot pellets, too.

But there is one other claimed effect of choke porting that I think is valid. Comp-n-Choke says that choke porting,

Improves shot pattern consistently
Slots grab the wad momentarily to allow shot to separate from the wad before exiting the barrel, improving shot pattern consistency.

Between the propellant gases and the shot is a plastic disk called the wad. It cushions the shot from the turbulent gases and seals the gases inside the barrel so they don’t blow by the shot on the way down the barrel. The gases push the wad and the wad pushes the shot. All three blast out the end of the barrel.

As mentioned, when the shot pellets leave the barrel they start to diverge from one another. It’s not for nothing that shotguns are also called scatterguns. The density of the pattern of shot on the target is made more uniform if you can find a way to retard the flight of the wad, getting it out of the rear of the center of the string of shot pellets. Otherwise, the wad can bobble about in the center of the shot string, reducing the shot density in the center - which hopefully is the part of the pattern that lands on the target.

Choke ports reduce the velocity of the wad two ways. One is by that gas venting, which is a tiny reduction in the accelerating gases pushing the wad. It is a tiny reduction because almost all the wad’s acceleration is accomplished by the time the wad reaches the choke, but immediately after the choke comes the open air, which obviously brakes the wad quite a lot - but not a lot for several feet. In that several feet the wad can bobble in the pattern. Even the tiny reduction of the wad’s speed caused by venting the gases can help. The other way the ports retard the wad is that they simply grab it. The wad is designed to expand from its center outward to seal the gases behind it. When the wad reaches the ports it tries to expand through the ports and that physically slows the wad.

My test firing of the new choke showed no difference in recoil, but I was destroying the targets more thoroughly. Instead of merely breaking apart, as most did with the old, unported choke I had been using, many more of the targets got blasted to clouds of brown dust with few fragments left to fall to the ground. Conclusion: I was achieving a greater pellet density in the center of the pattern than before.

Barrel porting: No! Choke porting: Si!

A follow-up post is here.