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Folks tell me my web-site as become a sort of "On-Line Magazine" for handmade Airguns.

I'm glad you are enjoying it. In that Spirit, following is an article called . . .

The Accurate Bullet

If you have a decent rifle, and buy decent bullets for it, you should get good accuracy . . . correct? Not always.

Let's talk about Bullet Design

The design and fit of those bullets is critical to the accuracy equation. You must understand the differences between slug designs to know how they may perform.

I'm forever testing new designs. It's alot of investment. I must manufacture a tool steel cutter to machine the cavity of a casting mold. I must then make the bullet casting mold itself. It's a vast amount of work to make a multi-fluted bullet shaped machine tool bit and then heat treat it properly. It's also a good bit of work to make a mold using that cutter. Then, I have to cast the mold, clean the slugs, and size them for the particular test rifle. The very first group I shoot might prove that the design is "wild". At that point, all of the above work would just become an expensive lesson.

Why bother? Why not just buy a box of slugs? Because, box bullets are designed first and foremost; to satisfy the general public, fit into the most rifles and pistols, and cause reloaders the least trouble. They are the "One Size Fits All" Suit. As with things of this nature - they satisfy the tastes of some and not others. If you want to look well dressed - you need personal attention.

Let's take a look . . .

This is a small photo of poor quality but it makes the point I wish to show you. I spent the day at the range yesterday. For later tests, I covered up the earlier holes. But; the white dots cover three holes (a group) shot with a new test slug design @ 50 yards. Not too impressive! That was alot of work for nothing. That's a nice tight 6" group @50 yards! Ha ha. Those pretty slugs flew properly oriented and punched nice clean holes - they just would not group. Lesson #1.

See any difference? This #26 Test Slug grouped into a cloverleaf @ 50 yards. Same identical set-up as above. Shot back to back. This one has promise! lesson #2.

OK, here's a test . . . Are you ready?


Both are 25 Yard 3 shot groups. Placement was different because I was "Holding Off" with a 75 yard scope setting.

Still - "groups are groups." Is this an "Accurate Bullet? It looks pretty good so far I'd say! Look at that group on the right - 3 slugs 45 caliber went through there.


AHhhh!, Now we learn something . . .

First, let's cover this issue of "Holding Off" - everyone might not understand that. Where you aim your sights, might not always be where the bullet strikes. If your gun, bullet, and sights are each accurate, but they are not "coordinated", your POA (Point of Aim) and your POI (Point of Impact) will not be together. You could shoot your rifle like this if you wanted. If you knew it shot four inches to the right and eight inches high, you could actually aim four inches left and eight inches low, and still hit your target every time. Sounds silly, for sure, but it's true. Why would anyone do this? Let's see.

If you are testing unknown slugs at multiple distances, you'd drive yourself nuts adjusting the scope to get things right. You would never know if the scope was set wrong or if the bullet was no good. You must take as many varibles out of the equation as possible. So; you set your scope for a known slug, at a known distance, and you let it alone. Done. That becomes your "Control". Don't touch it again!

Now. We pick one "Control POA". We always aim at that exact spot. We begin to shoot the unknown test slugs. We see that different designs and weights will group in different locations. In a perfect world, we'd see the heavier ones grouped alittle lower than the lighter ones. They'd all be in a nice vertical line depending upon the distance to the target. Wouldn't that be nice? Don't get used to it . . . It rarely happens.

When we look at our groups, we will note; A). Some have done just that - placed in a nice vertical location. B). Others grouped well but in an odd location (right or left). and C). Still others have completely gone "Walkabout" - the shotgun pattern..

Based upon the above, let's look at this most wonderful chart . . .

Lovely . . .

Yes, it was a piece of colorful rubbish I pressed into service at the range.

Now, you remember those beautiful 25 yard cloverleaves posted above? Well, remember I said I was using a 75 yard scope setting for a control slug. Actually - even that was grouping an inch or so right - I just never changed it. Now, when I shot those 25 yard groups, I needed to aim low (75 yard setting - shooting 25 yards - less drop). If you'd super-impose those 25 yard targets onto this chart, you'd see that I aimed at the orange POA and hit about 4" above it.

So; the location of the upper 25 Yard POI is shown on the chart (as computed from the 25 yard backer where I shot those targets). I was very pleased. I decided to see if these test slugs would fly well to 50 yards. I pressed this old shotgun riddled foam board into service. Please note the location of the lower left POI group (I still got a pretty good 50 yard group). But, look at the placement! It's five inches lower than the 25 yard placement. That's not good. But; what really seals it's doom is that it's seven inches left!

Bottom line?: This slug is very consistent. The rifle is amazingly consistent in shooting this slug each time. BUT - this test slug is a "Curve Ball". It does, what it does, the same each time. BUT; it's trajectory is unusable because it flies in a left hand compound arc (away from the muzzle and down). Nice clean holes. Consistent grouping. BUT - a "Curve Ball" all the same. It's of no use. Expensive lesson learned #3.

Here's a closeup of the target in the center of the chart. Here's my "Control Group" for this new slug test. That's a 50 yard three shot group with my Barnes 45 caliber Raptor Slugs. I know they are a winner.

Here's the control 25 yard group I shot with these Raptors. It's a fine tight, centered, 3 shot cloverleaf. I used a slightly left 6 o'clock hold for the scope setting I was using (remember that setting was grouping alittle right anyway - so a slightly left 6 o'clock was an appropriate correction).

Looking at the chart, you can see that my 50 yd. POA for the Raptors was also approx 6 o'clock left.

This shows the vast difference between slugs. While each slug groups well @ 25 and 50 yards: the Raptors "Stack". They shoot in a vertical plane. That makes all the difference in the world.

Let's talk about Slug Grading

You can't expect different things to behave the same. If your slugs are of different weights, they are different. If some are all beat up and others not - they are different. If they are of varying diameters, they are different. Think of it this way . . . it's like a quiver full of different arrows. Some have a feather off. Some are heavier than others. Some have the nock broken. Some are taped up. Etc. (That's the way we shot as kids - we had to compensate for each arrow we owned as we collected them over years and never retired one if we could help it).

Well, we're not kids anymore. if we want real accuracy, we need consistent ammo that fits our rifle.

Let's look at the difference.

This shows me that my #26 slug, that tested so well @ 50 yards, is still doing duty @ 75 yards.


Take a look. I shot these three groups back to back @ 75 yards.

When testing new slugs, it's alot of work to get everything ready and then cast a selection of each new type. There's no point going to the range with just a hand full of each. If I find a good design, I'll need to shoot many groups. By the same token, if I find the first group sprays all over the target, then I have a bunch of wasted work in that test batch. That's also why I can't go to the range with just one new batch. After a big set-up, I might be done in ten minutes if the slug won't fly. Because of this, I test several new designs at a time.

I cast and I size but I don't go to extremes grading each test lot. I already had seven different containers of slugs yesterday. If I'd have graded them too, I'd have had at least 14 containers and taken alot more time getting ready. It's best to just see if they "Want" to fly before investing alot of time in trophy slugs that might be a bust.

I said all of that to explain why I was shooting slugs of mixed grades yesterday. Now, please look at three targets posted immediately above. These were shot back to back to back @ 75 yards. The top one has a "double" at approx. 9 o'clock in the bull. The second one also has a 9 o'clock in the bull. The third has another 9 o'clock in the bull and a couple of more tightly by. That's no accident. I also didn't completely loose it when I shot those flyers. They were evidently #2 slugs.

So, at the end of a week's work, I have a new slug. #26 will go into the books.

Hope you enjoyed coming along and I hope you may have learned something.

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