BB vs pellet - air rifle question

I have a air rifle that I use to shoot squirrels out of my trees. It can either use BBs or .177 pellets. The pellets are heavier. My question is: Which has more energy at impact? The heavier pellet or faster BB when shot thru the same gun. (I assume the BB is faster cause it is lighter)

One of these I’ll have to take my cronograph out and compare velocities of pellets and BBs and calculate kinetic energy. Even withougt going to that much trouble I’d say go with pellets as they are bound to be more accurate and probably retain more energy at the target. The flat face of a target pellet is actually good for transferring energy to the target but you can get purpose made hunting pellets with pointed tips.

I suck at physics, but am experienced at sniping squirrels out of trees.

Go with the .177 caliber pellets. Specifically, I used to buy the hollow-point variety, which flatten out on impact for maximum anti-squirrel stopping power.

I’ve found that Long Island squirrels can take more than a few hits from BBs and still survive. The only way you can achieve maximum squirrel mortality is with the pellets.

I was trying to do the physics of the question but I am always wrong. So I thought I would let someone tell me. Does the 2 objects have the same speed leaving the barrel? (so the pellet has more energy at that point) If so which slows down quicker? I would say the pellet cause it doesn’t go as far. So the BB is moving faster at 50ft. Is the energy the same for each object while in flight ( smaller BB moving faster that heavier pellet)?

I agree with the previous posters that the pellets are almost certainly more lethal. However, if you have time to kill, do the experiment. Set up a block of soft wood, shoot it with BBs and pellets, and measure the drop from a straight line through the bore, as well as the penetration depth. You can get velocity from the drop, and a general gauge of energy from the depth of the hit into the wood. That, or build yourself a small ballistic pendulum.

Kinetic energy equals mass times velocity squared. So if two projectiles have the same weight, the faster one will have much more energy. And if you have two projectiles of the same speed, the heavier one will have a little more energy. In short, for projetiles with similiar weights, speed is the dominating factor in determining energy. (Though, don’t always assume that kinetic energy = lethality. That’s probably usually true, but not necessarily.)

As for your question, I have no idea which is better for killing squirrels. I wouldn’t assume that a pellet and a BB both leave the gun at the same speed - I could see the pellet leaving the muzzle faster since it has(?) a cup-shaped tail that would catch and contain the air pushing it out the barrel much better than a BB. But, I also suspect the pellet will slow down faster once it leaves the muzzle due to its less aerodynamic shape. This means it may end up having less energy when it actually hits, because it has slowed down so much on the flight.

Since actually working through the physics would be a truly brutal exercise, I suggest some simple empirical experiments instead. Get several (like, 10) layers of cardboard and bind them tightly together somehow. Then set them upright against something you don’t care about, at about the same distance you shoot at squirrels from. Shoot several BBs (five or ten) at one spot. Then shoot several pellets at another spot. Take the cardboard apart and see which (if either) generally penetrated farther. This will be a crude but still useful measure of which will hit harder.

Incidentally, what’s the problem with squirrels? Are they munching on the garden or something? Are they good to eat? No offense or anything, I’m just curious why someone would shoot squirrels. Squirrels are exceptionally useless, but I’ve never seen them as pests.
-Ben

Change in energy is equal to the force times the distance over which the force is exerted. The muzzle length is the same for both, so we don’t need to worry about that second part. The force on either projectile would be approximately the same, being equal to the pressure times the cross-sectional area. On this basis, I would say that the energies would be equal, so the lighter pellet would have the higher speed. I think, though, that the faster particle would end up feeling a slightly lower force, so the heavier particle would get the higher energy (I really need to review my thermodynamics). In either event, the heavier particle would have a higher momentum, and I don’t know whether energy or momentum is more significant in calculating desquirreling ability.

Assuming that all the energy deliverable by the projectile is absorbed by the target – the ever-deceptive and sometimes deadly squirrel – the question cannot be answered.

“Oh, sure, T!” you may exclaim. But I’m tellin’ ya’ll, the question can’t be answered.

I’m tellin’ ya’ll!

I second everything ModernRonin2 said, and with the observation that if your pellet gun has a rifled barrel, the lead pellet will likely be more accurate, because the lead may grab the rifling better than a steel BB, and therefore spin better.

That’s my experience anyway.

While we’re on the subject of personal pellet gun experience, I always had better luck shooting things with pellets because they were similar in speed, but the pellets had much more momentum and penetrated farther. With a .177 pellet gun, you’re going to need penetration, since the amount of energy is negligible compared to what you need to kill a squirrel. Basically what your’e hoping to do is poke a hole in him and have him bleed to death, ergo more penetration is your aim.

Go to the local sporting goods store & look for ‘field point’ pellets- they have a conical nose, but the same cup skirt.

I’m not sure that would lead to a good conclusion. The pellet(being lead) is assumed to deform more, causing more damage to soft tissue( on the other hand a air rifle shoots so much slower than a powder shot bullet that the deformation my be minimal). Much like a hollow point round. Even soft wood might be hard enough to defeat the deforming ability into a pointless loss of energy. If you can get your hands on a rump roast or something that might be more interesting.

• The pellets will be more accurate and retain more energy, even though they will come out of the barrel slower than the BB’s. IIRC, steel BB’s weigh something like 5.5 grains, and the lightest 177 pellet I remember finding weighed ~6.1 grains. Most .177 pellets weight betwen 7 and 12 grains. The formula for finding velocity<–>energy is Sqrt [ Ft. lbs(energy) * 450240 / (pellet weight in grains)] = velocity, in feet-per-second.
~
• Lead balls the same diameter as BB’s are also available, but inexpensive airguns don’t have much power and fire them rather slow. Also, many “BB” guns use a magnetic bolt to retain the steel BB inside the breech until it’s fired, and lead balls may roll out if you tilt the barrel down after loading. Lead balls do not ricochet like steel BB’s can, though (-if you shoot at an inflated car or bicycle tire, all bets are off).
• Accuracy is something else entirely: technically, “BB” guns’ barrels are bored a bit loose for pellets, even though pellets work. Pellet style doesn’t matter much in low-powered airguns, you just have to hit the vital area (usually the head). If you’re in the US, Crossman Copperhead pellets (the round-nosed ones Wal-Mart sells in the plastic belt clips) are some of the cheapest and most accurate available anywhere. - DougC
• There is such a thing as hollow-point airgun pellets: more than one thing, actually. Beeman (US) sells the Crow Magnum, Gamo sells the H-Point, and there were a couple cheaper ones out there last time I looked. They do expand when shot from most air rifles. I find them rather gimmicky and I doubt they help much, but I never shot at animals very often. One named the Lamprey was basically a normal pellet reversed, but it is no longer made.
• Pointed pellets tend to be the least accurate and round-heads tend to be the most, but even with a hollow-point pellet it’s not like you can go hunt buffalo. You always have to aim for the brain. Cecil Would Not Approve, but pigeons are legendary for getting shot completely through the chest, and then taking off and flying away. New airgunners are always shocked the first time they see this happen. - DougC

How many times do you have to cap the little buggers with an airgun before they keel over?

Wouldn’t a .22 be more effective?

Which is why I use lathe-turned Beeman Silver Jets. On a good day I have cracked a Champagne bottle with one shot using these little devils.

• Animals as large as groundhogs are commonly killed with single head shots.
• Well, yea, if you can use it (I have a 10/22 too, doesn’t everybody?), but sometimes an airgun is a better choice: less risk of damage from missed shots or shoot-throughs, no risk of shooting near flammable fumes, less regulation on airgun use than firearms and lastly, the fact that airguns are quieter than firearms: some airguns come equipped with unlicensed but legal silencers; gas-ram airguns make very little noise even without any silencer and what little noise they do make is basically unrecognizable as such.
• I bought mine mainly for [inanimate] target shooting. - DougC

KE = 1/2mv[sup]2[/sup], not m*v[sup]2[/sup]. Big difference.

Yes - but also more effective at having the police come out and confiscate your gun and put you in jail for violating city firearms ordinances.

Ok, I hit a squirrel in the neck at 25 feet. What would deliver more stopping power. The BB or pellet?

Second case: I case the devious squirrel in a live trap. So I put the gun on his head. Then the BB or pellet?
The rifle I have is the daisy that holds 50 BBs but you have to load the pellets single shot. So if the bastard is in the trees then you need the extra shots to get him. Then I shoot for the neck. I think a glancing blow off the head wouldn’t be effective. But if he is in the live trap then I just put a single pellet in and be done?

The reason I kill them is they have invaded our neighborhood. There aren’t enough big trees so they eat their way into our houses to nest. Quite destructive. Then the final straw. They sit in the branches of my prized pecan trees and eat the bark off . When I was sharing the pecans with them I thought OK. But then they started chewing on my trees and that was it. Of course the numbers have increased where I was not sharing the pecans. They were eating all of them. In 18 months, I have 70 graves in my backyard. (that doesnt include the ones that I hit and then got away). I just use a posthole digger to make a little round hole in the ground and thats it. They are just fertizing my trees and bushes.

I have a .22 air rifle. It doesn’t shoot bullets. I think that’s what black455 was on about. Not a .22 rifle that shoots bullets.

Use pellets, and headshots. Get a decent scope and zero it.

As far as the trap, a nice pair of heavy boots, sturdy pants, and a shovel work nicely, Gloves too. But if you dont want to squish it, just a head shot at close range will kill it.