Pneumatic Pnews

Monday, July 03, 2006

Tighten those groups! Pellet sorting brings extra accuracy

by Tex Force

When I want to shoot REALLY tight groups, I sort my pellets into groups by their weight and shoot only from one group.

Why sorting works
Any group of ballistic projectiles will perform more uniformly if they are exactly alike. The closer the projectiles are to each other, the less randomly they will act (there will still be variations).

There are probably an endless number of things you can evaluate on a pellet, but the weight is the one that gives you the greatest return on your effort. We can discuss the reasons why all day long - there might be a void in some of the pellets that destabilizes them in flight, a heavier pellet may be larger and therefore fit the bore tighter, etc. The discussions can go on forever, but it doesn't matter. Simply sorting pellets by their weight will improve their consistency, which means tighter groups. So how do you do it?

You need a scale
The best type of scale for this is a powder scale that reloaders use. It weighs very small amounts and measures in one-tenth grain increments. I just checked on ebay, and you can buy a scale for under $20, shipped.

Two kinds of scales
There are two kinds of powder scales - balance beam and electronic. They are equally accurate and measure in the same increments, but the electronic scale dampens much faster and is easier to use. With a balance beam scale, you keep adjusting the scale until the beam balances perfectly. The weight indicated is the weight you record. With an electronic scale, all you do is place the item on the scale and wait a few seconds for the readout to stop changing. The number that remains is the weight of the item. An electronic sale is about four times as fast as a balance beam.

A balance beam scale is accurate and inexpensive, but it takes longer to use.

An electronic scale is just as accurate as a balance beam, plus it works about four times faster. The price has dropped in the past few years. This scale sells new at Midway for less than $30!

Sort into groups
Once you have a scale, you can begin sorting pellets. A premium pellet will vary in weight by an amount that will sometimes surprise you. Let's look at Crosman Premier 10.5-grain .177 pellets for example. The weight is listed at 10.5 grains. When you sort, you will find that about 30 percent weigh 10.5 grains, another 35 percent weigh 10.4 grains. Twenty percent weigh 10.6 grains and that leaves 15 percent of the pellets that will weigh anywhere from 10.1 grains to 10.7 grains. Now, let's talk about what you do with these sorted pellets.

What to do with the different weight pellets
The three primary groups of pellets weigh 10.4, 10.5 and 10.6-grains. If I wanted to shoot the absolute best group possible AT LONG RANGE, I would use pellets from one group, only. If I were competing in a field target match, I'd use pellets from a single group. But here is the deal - IT DOESN'T MATTER WHICH GROUP YOU USE! That's right - with all three pellets, your group will shoot to the same point of aim out to around 50 yards. There will be very small differences, which is why you only use a single pellet weight, but the sight picture, in general, does not change. If you are shooting groups beyond 50 yards, then stick with a particular pellet weight because it starts to make a difference at that distance.

What about the lighter & heavier pellets you sorted?
As far as precision shooting goes, they're junk! They can be used for function-firing or in cheap airguns, but don't use them when you want the best accuracy. The lighter pellets are the worst, as far as accuracy goes, because they are the undersized pellets. They will give a precision airgun lots of trouble.


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