Choosing the Right Pellet for Air Rifles

[brihacharan]

Hi Guys,
Here’s some food for thought – Hope it helps ‘Enjoy your Shooting’

There are so many factors that can affect air rifle performance hence choosing the proper pellet can be a difficult task. Individual characteristics of the air-gun and pellet combine to play a major role in determining how well a particular pellet will group in a specific gun. A spring air-gun's rifling and choke, spring and spring guide tolerances may have a positive or negative effect on the performance of a given pellet. Additionally, pellets are sold in different shapes, weights, lengths, diameters and alloys. Combining all those factors can make choosing the proper pellet quite confusing.

What attributes make a pellet a good choice?
The type of shooting task at hand will largely determine the ideal pellet. For general reference, we break shooting tasks into four main categories:
1.General Shooting (plinking)
2.Pest Control
3.Hunting
4.Target Shooting
• But one pellet attribute is essential regardless of your shooting type is its ability to group well with your gun in a consistent, repeatable manner.
• It doesn't take more than a few shots to determine whether your gun performs well with a given pellet. If your gun can't shoot a tight group with five shots, then it won't perform any better by shooting 100 pellets. The first thing to do is to then is to look for other attributes such as:
1. Pellet shape - different shapes are designed to perform different shooting tasks.
2. Pellet weight - important for trajectory purposes and velocity results.
3. Pellet hardness /softness assists hunters & pest control shooters to achieve humane kills.
4. Pellet energy - remaining energy at the target (Kinetic Energy) is vital to for knock-down power.
• It is important to remember that attributes important for one shooting type may not be important at all for another shooting type. Knockdown power, for example, is important to a hunter or pest control shooter, but of little importance when shooting paper targets.
• However, if the shooting emphasis is field target competition rather than paper target shooting, a certain amount of knockdown power is required to trip the metal targets.
• At this point, let's assume that the shooter has tested all the pellet types in the pellet sampler and has determined the type of pellets that group best with his air rifle.
• Now it's time to look at the other pellet attributes and the next step is to choose a pellet type for your particular shooting need.
 The following paragraphs explain the four basic pellet shapes and their basic functions.

• PELLET SHAPE
1. DOMED/ROUND HEADED PELLETS-are great all-around, general use pellets. The round head is very aerodynamic and is good for shooting at longer distances (over 25 yards). Oddly enough, round-headed pellets have the highest ballistic coefficients of all the pellet shapes, making them a great choice for pest control and hunting. Pellets with high ballistic coefficients generally have more knockdown power at the target.
2.WADCUTTER Pellets-are wonderful target pellets. Their flat heads make nice, clean holes in paper targets which is essential for easy scoring. They can also be used for pest control but it is good to remember that they are not designed to be long-range pellets and any breeze or wind pushing against the pellet's flat head can easily make groups open up at longer distances. Generally they are at their best at shorter distances of 20 yards or less.
3.HOLLOW POINT Pellets-very good hunting pellets that really expand on impact. They are popular with pest control and hunting shooters. But remember that they have the same weakness as Wadcutters because the big hollow mouth on the pellet catches the wind and may open groups at longer distances.
4.POINTED pellets that seem to work best in light to medium powered air-guns. They have good penetration capabilities for hunting and pest control. But they don't generally work as well with magnum or super-magnum air rifles as the domed / round headed pellets. It’s recommended in general that pointed pellets be best used with a lighter or medium powered air rifle.
PELLET WEIGHT
•The weight of the pellet is important because it can affect trajectory, impact power, velocity and aerodynamic stability. Heavier pellets tend to be more stable in breezy conditions and also retain their energy better over distance. And they hit much harder at the target, as one would expect. But that doesn't mean a person should rush out and purchase the heaviest pellet in any caliber. It is important to match the weight of the pellet to your gun's design capabilities and power level.
•Spring powered air-guns, for example, are known to work much more efficiently with medium weight pellets. Using the heaviest pellets in a caliber with a light or medium powered spring air-gun can actually shorten spring life on some light or medium powered air rifles. Gas piston and high power air-guns on the other hand, are not affected adversely by using the heavier pellets.
•Pre-charged Pneumatics (PCP's) actually work more efficiently with the heavier pellets. As a general rule of thumb, light and medium powered spring air rifles operate best with pellets that fall in the middle of the weight range of any caliber. The high powered spring, gas ram and PCP air rifles can use the heavier pellets without damage.
Cheers
Brihacharan

[Big Daddy]

Hi Brihacharan
A small clarification. Assuming I use two different types of medium weighted pellets (say domed and wad cutter) both in ideal environments.
The Wad cutter gives me a decent grouping and the domed not so decent (say at 500 fps average).
If I were to increase the swept volume of the same gun among others, resulting in the increase of say 750 fps, would the grouping remain same for the same pellets or could there be a change in the grouping of both types of pellets? Or can grouping be attributed only to the rifling (again assuming ideal conditions)

Regards,

BD

[brihacharan]

Hi Big Daddy,
> Very interesting question!
> There are too many variables as far as grouping is concerned -
1. The weight of the pellet
2. Its shape (Dome / Roundhead, Flat Head, Pointed Head & Hollow Head) Each of these buck the wind differently, when fired, creating different ballast - hence no two pellets shaped differently will give similar grouping, although they may be of the same weight.
3. Composition (Full Lead, Alloy or Combo - PBS)
4. Outside wind velocity
5. Rifling of the barrel
6. Configuration (Fluting, Fitment or seating)
7. FPS the gun can deliver
8. The design & construction of the gun (PCP, CO2 & Side or Underlever Guns are truer than Springers)
9. Distance from the muzzle to the impact point (taking gravitational pull)
> This is one reson why shooters before going on a specific mission (Targetting / Plinking / Hunting) zero their weapons each time with type of pellets they want to use at that particular time.
> This subject comes under the umbrella topic "Ballistics" and is endlessly debated.
> My advice is that if you are so particular - Choose the pellet for the appropriate ocassion & Zero your gun accordingly. > > This is what True Air Gun aficianados do!
> So good luck - Happy Shooting!
Cheers
Brihacharan

[fantumfan2003]

In the Indian scenario the Dianashot, Mastershot and Gsmith pellets give acceptable groupings.
Most .177 guns including IHP group very well with match and domed pellets from all the above manufacturers. Thank god for that one.....

M.

[Atanu]

Hi Brihacharan,

This is indeed a very interseting and informative post, about the differet types of pellets and their use.

The pointed pellet is best for medium powered air guns. This means that for my IFG 35, I should stick to these?!

Atanu

-- Fri May 14, 2010 9:34 pm --

Hi Brihacharan
A small clarification. Assuming I use two different types of medium weighted pellets (say domed and wad cutter) both in ideal environments.
The Wad cutter gives me a decent grouping and the domed not so decent (say at 500 fps average).
If I were to increase the swept volume of the same gun among others, resulting in the increase of say 750 fps, would the grouping remain same for the same pellets or could there be a change in the grouping of both types of pellets? Or can grouping be attributed only to the rifling (again assuming ideal conditions)

Regards,

BD

Hi Big Daddy,

Interesting question, but I am more interested to know as to how the swept volume can be increased. Is this possible to do?

Lets say, I reduce the length of the piston in my IHP 35 from the front side and install the washer again. Will this do?

BR// Atanu

[Big Daddy]

Hi Atanu,

Hope this is helpful. viewtopic.php?f=22&t=9315&p=96025#p96025
A few other factors (among others) also can be considered to find more scope for volume, like when you break your barrel (before corking), the gap between the pellet chamber and the compression chamber port can be reduced if there is scope, after corking your rifle press the barrel further down and see how much more the cocking lever travels. Some of this space can be utilized. But this might mean re-fabricating the entire piston assembly. I’m not a gun smith but just sharing what I learnt from some one. PKJeetesh could throw light on this. To the gurus out there, my apologies if I’m wrong about the methods of finding more scope for volume. .

[brihacharan]

Hi Big Daddy / Atanu,
> Believe me guys, there are certain limitations to increasing the power of your Air Rifles.
> An Air Rifle that can generate 700 to 800 fps and give groups of 1 1/2" to 2" at 20mtrs (approx. 60ft) is excellent. Even overseas experts say this. This is a good combination of Power + Accuracy.
> Consider this - If swept volume were to be increased from the existing to 15% t0 20% more - have you ever taken into account the size of the "Tube - Powerplant"? The engineers who designed the original rifle must have provided a certain length, diameter(OD & ID) and meturllurgical composition to it.
> Hence if you re-size the piston to gain Swept Volume - Wouldn't you want to consider the same to the "Tube - Powerplant"? What I mean is if the Piston is re-sized, shouldn't the PP also be strengthed viz. OD & metallurgical composition.
> Eg. If in a standard 4 cylinder car, you increase the dia of the cylinder by re-boring & put oversized pistions to suit it - will the engine block be able to take the extra pressure?
> In my considered opinion "Tuning should be done to OPTIMIZE performance & accuracy" and not supercede the basic laws of 'Physics & obsession with magnumitis'.
> As far as Pellets are concerned use what suits you & your gun the best, under the circumstances in which you use them.
Cheers
Brihacharan

-- Mon May 17, 2010 3:06 pm --

Big Daddy » Fri May 14, 2010 3:46 pm

Hi Brihacharan
A small clarification. Assuming I use two different types of medium weighted pellets (say domed and wad cutter) both in ideal environments.
The Wad cutter gives me a decent grouping and the domed not so decent (say at 500 fps average).
If I were to increase the swept volume of the same gun among others, resulting in the increase of say 750 fps, would the grouping remain same for the same pellets or could there be a change in the grouping of both types of pellets? Or can grouping be attributed only to the rifling (again assuming ideal conditions)

Hi Big Daddy,
> Yes. Different pellet weights with different fps will differ in their groupings.
> It's the simple principle of "Aerodynamics'.
> The velocity will have have an impact on the 'Ballast' the pellet gets.
Eg. In powder fired guns, the shooter using different grains of bullet weight (in 30-06 caliber - 150gr, 165gr, 180gr & 220gr) will use different types of powder. Because of the velocity the respective ammos generate. The lighter ones shoot flatter than the heavier ones. Even the configuration of the bullet, whether pointed, round soft nosed, full metal clad, boat tailed, silver tipped - all perform differently.
> That's why shooters "Zero in" their weapons everytime depending on the type of shooting they plan to do.
> Rifling also plays an important part in the flight of the bullet / pellet. Rifling in smaller calibers have a ratio between Pitch & Landing of 1 in 12 or 1 in 16, where as the heavier calibers have 1 in 8 or 1 in 10. It's a precise subject that involves Physics (Velocity / Ballistics / Aerodynamics / Gravity / Thrust....)
> Hope with my limited knowledge I've been able to explain as best as I could)
Cheers
Brihacharan

[drifter]

Hi,

This post is very interesting, was curious to know what make and specification of pellet would be ideal for the 54 airking. Is it ok to use the gsmith pellets, is the quality good enough?.

[brihacharan]

by drifter » Tue May 18, 2010 3:33 pm
Hi,
This post is very interesting, was curious to know what make and specification of pellet would be ideal for the 54 airking. Is it ok to use the gsmith pellets, is the quality good enough?

Hi drifter,
> Frankly there is nothing like an ideal pellet for a specific gun.
> All depends on what kind of shooting you are planning - Targetting / Plinking / Pest Control / Hunting.
> Caliber apart, the make & quality of pellets is VERY IMPORTANT.
> Use preferably lead pellets - Avoid alloys (some pellets have antimony & these are comparatively hard - will foul your barrel.
> GSmith pellets are good - some shooters have complained about its fitment in the breech - could be an odd case.
> Use the different types I've mentioned in my post and zero in on what suits you best - accuracy is more important than power. If you can get groups of 1 1/2" to 2" at 25 yds consistantly - consider it good.
Cheers
Brihacharan

[santhosh]

Hi,
I used Gsmith Pointed high speed and high impact in my IHP 35 .22 the finish of the pellet is good how ever you have to push it really hard to get it inside the barrell but it gives good grouping however master shot is easy to seat buy i dont get the grouping with this lots of fliers.

I still prefer mastershot to Gsmith because of the ease of use and cost.

Regards
Santhosh.b

[Big Daddy]

Santhosh,
What gun do you use?

BD

[santhosh]

IHP 35m .22 caliber