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pellets out of smooth bore barrel

Posted: Thu May 14, 2009 12:34 pm
by qwerty
Hi, i've just finished my first pellet rifle and it shoots at about 400fps but ive got a smooth bore barrel so they just spin around in the air can tell me if there are any pellets that fly straight out of a smooth bore barrel or something like self rifling pellets.

Thanks

Posted: Thu May 14, 2009 12:42 pm
by Ragnarok
What kind of pellets are you using now?

You've got me a bit confused, because most diablo pellets (which make up almost all air rifle pellets) drag stabilise... They might not be incredibly accurate without rifling, but they shouldn't randomly tumble.

Posted: Thu May 14, 2009 1:01 pm
by qwerty
I dont actually know what pellets i am using because i got them from a friend but the are dome heads

Posted: Thu May 14, 2009 1:17 pm
by Gippeto
What "exactly" do you mean by "spin around in the air"?

Are the pellets "corkscrewing" as they travel, or are they punching "irregular" shaped holes in paper? (hitting sideways)

I suspect the problem is corkscrewing?

A place to start would be to make sure the muzzle is cut as squarely as possible, and relieve the inside edge slightly, but evenly. (evenly is VERY important)

Sand paper and a ball bearing or marble will work reasonably well as a tool to relieve the edge. (Crowning the muzzle.)

Can you provide the following information?

Your barrel id.
Pellet size. (.177 or .22 is most likely)
Range at which you are experiencing the problem.

Posted: Thu May 14, 2009 1:22 pm
by Ragnarok
qwerty wrote:I dont actually know what pellets i am using
When I talk about Diablo pellets I'm talking about what are sometimes known as "skirted" pellets.

They're this shape for three reasons:
1) Reducing friction by only contacting the bore at the circumference of the head the base of the skirt
2) Making it so that the lower pressures can obturate the pellet to fit the bore
3) So they fly naturally fly stably, even from an unrifled airgun

You are presumably using them, so aside from a certain amount of wonder at HOW you know something so small is tumbling, I'm also confused at why they're tumbling at all.

What's the fit of the pellet in the bore like?

Posted: Thu May 14, 2009 1:27 pm
by thedeathofall
Of course if you still have problems, you can use bbs instead....

Posted: Thu May 14, 2009 1:43 pm
by qwerty
its a .177 and the seem to be punching holes sideways

Posted: Thu May 14, 2009 1:45 pm
by qwerty
the pellet fits almost perfectly

Posted: Thu May 14, 2009 1:58 pm
by thedeathofall
first of all don't double post. there is an edit button.

secondly, without rifling there is little chance of getting conical shaped rounds to not tumble in flight.

I say you would be better off with bbs. they are cheaper and will be more accurate that a tumbling pellet.

Posted: Thu May 14, 2009 10:19 pm
by Carlman
@thedeathofall: Did you jst ignore Rag's post or...

As said above check for buring or some form of inconsistancy on the muzzle, thats probably your culprit

Posted: Fri May 15, 2009 9:45 am
by qwerty
the muzzle seems to be fine hasn't been cut buy anything like saw it was like that when i bought it so it has probably been cut by machinery.

Posted: Fri May 15, 2009 11:03 am
by thedeathofall
In my experience, and what i have seen from this site, there is very little you can do.

If your barrel is clean and straight, your muzzle cut straight, and your ammo fits, then there is only one logical explanation; the fact that you don't have rifling.

The other factor may be the pellets. I will sometimes get irregular pellets that tumble in my rifled airguns.

@Carlman,

Yes i did read Rag's post. I respect his opinion, and he is probably right. But the point of a public forum is to get several opinions, and all I did was state mine. There are several people the regularly post here and many people respect them more than others because of their experience. That does not mean that they are always right, nor does that mean we can't contradict them. (yes I know I used a double negative in that last sentence, but I cant think of a better way to put it.)

Posted: Fri May 15, 2009 11:15 am
by Carlman
I was not implying that you are not entitled to your opinion, meerly that he was speaking the truth.

Pellets are designed to be stable in flight whether shot from a rifled barrel or smoothbore. Some pellets are even made for smoothbores.

Posted: Fri May 15, 2009 11:31 am
by Ragnarok
thedeathofall wrote:That does not mean that they are always right
You seek to belittle me, sir! You leave me no choice but to challenge you to a duel!

Posted: Fri May 15, 2009 11:43 am
by thedeathofall
HAHA i said not "always" right. In your case, you are usually right over 95% of the time.

@Carlman,
I understand that pellets are designed to be "more" stable in flight, however they are not perfect and will not always give you a perfect flight. I personally think it has more to do with pellets themselves and/or the inside wall of his barrel than anything else.

@QWERTY

Check the inner diameter of your barrel with a caliper to make sure it isn't too big. If the barrel is too big, then the pellets wont fit correctly and will tumble.