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Sunday, March 13, 2005

This started out as a simple post on recoil, and has turned into quite an essay. I've divided it up into halves, and will post the second half (on technique, training and mental preparation) when I get the chance to finish it.

Recoil

Most shooters have trouble at times with recoil. It has been my contention that, for most of us, recoil can be effectively managed to a greater degree than we think, through a combination of equipment, technique and training, and mental preparation.

What is recoil?

Recoil is the result of Newton's third law, "For every action there is an equal, and opposite, reaction." It is caused by the acceleration of the bullet and the propellant down the barrel and out the muzzle as the rifle is fired. Recoil increases as bullet weight and velocity increase, and recoil can also be slightly higher in two seemingly identical rifles if one uses a less efficient case than the other. For example, a .30-'06 launching a 165 gr. bullet will recoil VERY SLIGHTLY more than the same rifle in .308 launching the same bullet at the same velocity, all other things being completely equal. This is because the .30-'06 uses about 10% more powder to accomplish the same task, and that powder is ejected at supersonic speed (as gas) after the bullet leaves the barrel. This is normally not a significant factor in felt recoil, though. I have also heard analysts whom I respect say that tighter rifling (faster rate of twist) increases recoil, and while I am willing to acknowledge they might be right, I don't understand the mechanism.

One thing that most shooters will appreciate is the rate at which the recoil is applied, or the sharpness of the recoil impulse. Two rifles that deliver the same number of pounds-feet of recoil will feel dramatically different on the shoulder if one uses a small, fast bullet and the other uses a larger, slower bullet. This is largely dependent on the specific cartridge used, and is usually described as the difference between a "shove" and a "smack." This difference is compounded by the fact that lighter, faster bullets leave the barrel with much more pressure behind them, causing a much larger muzzle blast. It is this blast, rather than the recoil impulse, that most shooters find objectionable.

Recoil does not act directly on the shooter, rather it is transmitted to the shooter through the rifle. It is at the rifle/shooter stage that we can help minimize it's effects. Felt recoil is what you feel after the bullet and powder have accelerated the rifle back into your shoulder, and what you are feeling is the stresses on your body as it slows down and stops the rifle.

Equipment

Factors within the rifle that affect felt recoil include weight and center of gravity of the rifle, the size of the contact patch that the rifle has with your shoulder, what the rifle does with exhaust gasses after the bullet leaves the barrel, and the cushioning both in the rifle itself and between the rifle and the shooter.

Muzzle brakes

Many shooters will install muzzle brakes on their rifles to reduce recoil. Muzzle brakes work by redirecting some of the propellant gasses as they leave the muzzle, which redirects the recoil impulse. If the gasses are redirected evenly and perpendicularly to the bullet path, they cancel each other out and the rifle recoils fairly normally but somewhat less than it did without the brake. If the gasses are redirected asymmetrically then they will push the front of the rifle one way or another. Traditionally, this effect is exploited by directing gasses upward, which will act to help keep the muzzle down which allows for faster recovery between shots.

It is my feeling that muzzle brakes offer a poor tradeoff for most sporting rifles. There is no free lunch, and that energy that would have been directed downrange will instead be redirected sideways around the shooter and any bystanders. We all learned in kindergarten that we should share with others, but trust me here, your friends won't appreciate sharing your muzzle blast. Most guides, fellow shooters at the range and range officers and instructors take a dim view of muzzle brakes for this very reason. Let me leave you with the strongest argument I have against muzzle brakes: they cause an increase in the damage to your ears (permanent damage which cannot be reversed under any circumstances) to alleviate a sore shoulder (which most people will completely recover from through the application of aspirin, ice or time). Make your own decision.

The one muzzle brake that I do appreciate isn't thought of as a muzzle brake at all. If you've ever fired a suppressed (silenced) rifle, you'll be amazed at how much less they recoil than their standard counterpart. Part of it is the added weight of the suppressor, but this is minimal compared with the effect of trapping the majority of the exhaust gasses and keeping them from adding to the recoil impulse. Sadly, though, suppressor equipped rifles are proscribed in many jurisdictions and even those where they are legal usually do not permit them for hunting, fearing an increase in poaching. While interesting, they are nothing but a sidenote to the discussion for most of us.

Cushioning

The primary means of reducing recoil on a rifle you already own is to install a thicker recoil pad. Slip-on pads can be used, but most people will prefer to have a good quality pad cut and permanently fitted. Most gunsmiths can do this without difficulty, and installation time is about 30 to 60 minutes. Be sure to leave yourself enough time for the smith to get to it, however, which can take anywhere from a few hours to a couple of years (can someone please explain to me why it is that gunsmiths, good or lousy, all seem to have a ridiculous backup of work?). Make sure that when you do install such a pad, that you choose one that is not only thick but also malleable (squishy). The more cushion the pad has, the more it will decrease the peak pressure impulse that hits your shoulder, making the rifle more comfortable to shoot. Two of the best after market pads that I am familiar with are the Kick-eze and the Decelerator, and I am hearing interesting things about the Limb-saver.

One common complaint about the pads mentioned above is that they don't last very long, and will flatten out and become both unsightly and less effective over time. These pads do eventually deform and look squashed, but there's a little trick to make your kick-eze or decelerator last quite a lot longer. When you store your rifle hang it in a rack lengthwise or, if you must store it vertically, do so upside down with it resting on it's muzzle. The weight of your rifle on the squishier pads eats them up rather quickly, and keeping the weight off of them should double or triple the life of those pads.

Weight and center of gravity

Another common method of reducing felt recoil is to add weight to the rifle. The most common way to add weight to a rifle is to instal weights or recoil reducers to the stock, but the best way is to select a rifle that has enough metal in the barrel and action in the first place. Adding weight to the stock dramatically increases the stresses between the barreled action and the stock, even while that same weight is making the rifle more comfortable for you to shoot. A heavier barreled action, on the other hand, helps reduce the pounding that the stock takes. With rifles that recoil significantly, over time they tend to "shoot loose" or shoot out of their bedding, resulting in poor accuracy and eventually ruining the stock. Synthetic stocks are not immune to this problem. I've seen magnum and heavy rifles completely destroy the bedding pocket in very high dollar synthetic stocks. I have experience with a custom .458 Lott that was built by a top gunsmith (but one with little experience with rifles in this class) that pulverized 3 different synthetic stocks, being re-bedded 6 or 7 times to no avail, in a misguided attempt to keep the weight to a minimum by using a thin barrel. I have a later production model from the same gunsmith, after the barrel weight lesson had been learned, that is reliable, durable and a dream to shoot. The only significant difference between the two is the taper and weight of the barrel.

The rifle's center of gravity also makes a difference. Visualize a rifle recoiling in the hands of a shooter, and you'll see what I mean. The butt of the rifle moves through the shortest distance, and it is essentially the fulcrum of the shooter/rifle interface. The muzzle, on the other hand, moves the farthest, recoiling both to the rear and upward several inches. By having the center of gravity farther forward, you effectively increase the amount of mass that the rifle recoils against without increasing the weight of the rifle. Yet another reason that choosing a heavier barrel makes more sense than adding weights to the stock. If you do choose to add weight to the stock, my preference is to try to add lead to the area under the barrel channel rather than inserting weights or recoil reducers in the buttstock.

Stock design

Proper stock design will also contribute to reducing recoil's effect on the body, with a straight stock that is well fitted to the shooter being the preferred layout. This is another area I don't fully understand. It seems to have to do with placing the recoil squarely on the center of the buttstock and having as little rotational or off-angle component as possible. All I know is that there is a difference, even if I am unclear on the exact mechanism.

The footprint of the buttstock on the shooter's shoulder is also a factor, with a broader and deeper contact point spreading the recoil out over more of the shooter's flesh and reducing the pressure at any one point. There seems to be an upper limit in payoff, though, with too broad a recoil pad not fitting into the pocket of the shoulder. Choose a rifle that fits your shoulder is the best advice I can offer here.

One last stock design feature that I've not seen discussed anywhere else is the amount of flex or compression that a stock goes through during the recoil impulse. I first heard a rifle designer discuss this a couple of decades ago, and I thought it was complete horse byproduct. He mentioned it in a discussion of the relative merits of walnut versus birch stocks, and claimed that a birch stock tended to recoil less because birch was more flexible than walnut. I couldn't imagine that a stock could flex enough to make any difference and still be durable enough to last more than a few shots. The only reason that I'm keeping an open mind is that I recently acquired a rifle with a Hogue Overmold synthetic stock, which is made of rubber over a synthetic base. I don't claim to understand it, but I swear I can feel the stock flex during recoil and kind of spring back into shape in the milliseconds afterward. All I know is that this rifle kicks less than any comparable rifle I've ever shot in the same category. I report, you decide.

Saturday, March 13, 2004

I got a note from a my Father today, about Portland, Oregon's police force replacing all of their Glock 45's.

"An article in this morning's Oregonian says that the City of Portland is replacing all 230 of its Glock 21 .45 cal handguns after 2 of them "blew up" (with minor injuries to officers) while being shot at target practice on March 1.  One additionally "catastrophically failed" a year ago.

"They claimed that they examined the ammo and it was not a case of faulty loads.  The bureau is replacing them with 9 mm versions.  Seems like a step backwards.

"Have you heard of such failures?"

Here's what I wrote him back:

Yep, happens all the time with Glocks in .40 S&W and .45 ACP.  I've probably examined half a dozen that that have blown up.  Happens in Glocks that digest either large quantities of cast lead bullets, or small quantities of swaged lead bullets.  Even that isn't enough to do the deed, though.  The gun then has to be improperly cleaned (not removing the fouling from the barrel) and then fired with relatively full power jacketed bullets.  The jacketed bullet starts down the barrel, pushes a bunch of fowling ahead of it which increases friction dramatically, pressure spikes, and Kaboom! ! ! !  The chamber splits into two sections, top and bottom, along the weakest cross section, which is horizontal (parallel with the horizon as the pistol is held upright in your hand).  If you look at your barrel in that area, you will see that is has less steel there than any other cross sectional area.

The good news here is that I don't know of anybody that's ever been seriously injured in one of these incidents.  The bullet is fired out the front, the chamber splits, the gun won't cycle, and no further firing is possible.  Usually the shooter is bruised and possibly "peppered" with hot gasses, and the pistol is totaled, but no major harm, unless you're using it to defend yourself, in which case you're screwed.

The interior barrel contours on a Glock are radically different from traditional pistols.  Herr Gaston Glock wasn't any kind of a shooter himself and when he designed the first Glocks he used input from European police and military agencies.  None of them shoot anything like the quantities that US police and military shoot, and consequently they don't use lead bullets (which are strictly an economizing measure).  Those barrels are designed to spin-stabilize jacketed bullets, to decrease fouling by not having lands that cut into the jackets of the bullets and to last for a long, long time.  They are not designed to operate when heavy lead fouling is present, because they never anticipated that there would be any in the barrel in the first place.  His rifling design is far, far superior in all respects to traditional rifling, and has been heralded as one of the great leaps forward in firearm technology.  But not if you shoot lead bullets.

Look into the rifling of your Glock, and you'll notice no visible lands and grooves, just a spiraling smooth surface.  If you remember your firearms history ("Tales Of The Gun" on The History Channel is great for this) you'll recall that rifling was originally straight, and was cut into barrels to allow continued firing in spite of fouling.  Land and groove rifling allows jacketed bullets to "pass over" or "ride on top of" a large amount of fouling without harm.  Glock rifling does NOT.  It was never designed for it, and it's not surprising that it doesn't do it very well.  It was only later discovered (by accident, if I remember correctly) that spinning the rifling stabilized the bullets and improved accuracy.  It was not originally a design feature.

The solution is quite simple.  Shoot only jacketed or cast-plated bullets in your non-9mm Glocks.  The 9mm appears to have sufficient strength to not have this problem, but I still don't shoot lead bullets in them.  Also, since they don't spin-stabilize soft lead bullets worth a hill of beans anyway, there's no great loss in not using them.  I tried cheap lead bullets in my Glocks in the late 80's, and found that they keyhole at distances as close as 7 feet.  Not worth the effort.  Rainier plated bullets are about 15% more expensive than pure lead cast bullets, don't foul, don't give off aerosolized lead particles, and are much easier to load.  That's what I use in just about anything these days.  I don't even bother with straight cast bullets anymore.

Monday, March 01, 2004

TRUE SURVIVAL OF THE FITTEST

How do women do it? Is it the lifetime of being treated as second class citizens? The fact that they have to exert twice as much effort to accomplish anything physical when compared to a man? Or is it simply that whole childbirth thing, where if they weren't so strong and resilient then the species would die off in a few generations? I don't know, I'm just amazed every time I see it.

My better half flew out last Sunday afternoon, but the airplane broke down over the ocean and returns to Honolulu. They hold the passengers hoping for a fix 'till 1 am, then give in for the night and decide to find hotels to put everybody up for the night. She wants to come home, but I have the only set of keys to the new apartment, security is pretty tight and you can't get in without them, and I'm so tired I don't wake up to the sound of the phone. Since she can't get in to the apartment, she accepts the offer of the hotel they're putting everyone up in (three blocks from our new home). When she tries to eat at the restaurant, she finds out that the food coupons they gave everybody to eat at the hotel for some reason aren't actually, you know, accepted by the hotel.

The keep telling the passengers that they'll be leaving "soon," but delay from one flight to the next. She finally gets on the 4 pm Monday flight (by calling customer service repeatedly), and when she attempts to get to the airport on the hotel shuttle she finds out that they won't accept her without charging her $10 ('cause the airline didn't arrange for transportation BACK TO THE AIRPORT!). She races to get to the last shuttle that can take her in time, and slips and falls down a flight of 9 stairs with all her luggage in her arms. She breaks both of her shoes and turns her entire forearm into a massive purple bruise (looking at it one week later I can't see how she didn't break the arm, you can still see the DENT in the muscle where it landed on the edge of a step). Fortunately, she doesn't make her back any worse (did I mention that she had been to the doctor 3 days prior to all of this for a blown out back? She's supposed to be taking Vicodine and staying in bed, but she's instead trying to cure herself with just Ibuprofen and a full-throttle business trip), but she DOES break her tailbone in the fall. Now she's got to sit on the plane for 6 hours, then spend the week driving around and interviewing potential customers for a client.

She gets to the hotel Monday night/Tuesday morning (about 1 am), and the toilet doesn't work. She gets up in the morning and the shower doesn't work. She gets out on the road and does 12 hour days to make up for the lost day, and, being the stubborn, driven person that she is, she finishes interviewing every nursing home on her list with about 2 hours to spare on Friday. Where upon she flies back to help me finish up moving to the new apartment, broken tailbone, thrown out back and now a cold all combined.

The next day (today) we found out that her leather couch (which cost about $5,000 and is the only nice piece of furniture we own) does NOT FIT INSIDE THE APARTMENT. Simply no way to maneuver it into the place without knocking down a concrete wall, which is load bearing for the 7 floors above us. So she gives it to one of the guys helping us move, has her first emotional outburst of this whole ordeal (minor, and well deserved) and we get done tonight at around 11:00 PM. Her new job and first day of training start at 7:00 am tomorrow.

And she keeps going. I don't know how, but she does it.

Friday, February 27, 2004

I'm new to this blogging thing, so I'm sure I'll be making some assumptions about what I can do here that later turn out to be not true or not easy. How do I know this? Well, I assumed since all of my favorite blogs have COMMENTS that I would have one too. Dang, where's that Blogger Pixie Dust that was supposed to come with the new account . . . .

Looks like I'll have to actually hit the help button and see what I can find. Dreck! I guess there's a difference between "simple to use" and "even a simpleton like you can get everything working in 3 easy steps."

In the mean time, if you want to send me a comment you can e-mail me at "frmrflyer AT aol.com"

Thursday, February 26, 2004

Welcome to my blog. Now that there is no possibility that I will be accused of being leading edge, it's time to start one up myself!

What will you find here?
Freedom, Liberty and a dash of good old American Business.

Who is FormerFlyer?
A medically washed out commercial pilot that had to go back to the working world and get a job. These days I'm a midlevel executive for a healthcare business in a resort city way out west of the Mississippi. Hint about resort cities: they're much nicer to visit for a week or two when you can afford to pay people to be nice to you than they are to live in. When you live in one, it's different. Trust me.

Why bother coming around to visit?
I intend to write about things that interest me, and I hope that some of you will be interested as well. Topics are likely to include business, entrepreneurship, aviation, firearms, pets, freedom, liberty and responsibility.

I hope that the selections to come bring you information, comfort, enjoyment or cause for thought. If you find you like something enough to take a moment of your time to respond, I promise to read what you write. Trolling, flaming and abusive behavior will get your posts removed without prejudice. Let's keep it civil, and go for more light than heat.

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