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megalomania
March 4th, 2003, 01:50 AM
HMTD Factory
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From:
Registered: FEB 2001
posted February 07, 2001 11:23 PM
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Hmmm...where are other old faces? Have they all evolved into forum moderators? Oh well, guess I will drop in as a newbee now...
Here's some tricks about airgun pellets that I gathered and experimented in the past few monthes while I was absent(so will I be absent later). Hope you enjoy them.

1. How to boost pellet velocities.
2. Exploding targets.
3. Exploding airgun "plinkers".
4. Exploding airgun pellets.

1.How to boost pellet velocities.

Idea came from past issue of "AIRGUN"magazine of Britain. Without modifying airgun itself,
one way to boost airgun energy is to plate
the pellet with brass.

You need a film can (short and stubby black polymer ones that you get when you buy a roll
of film) and some brass coins like a Canadian loonie. The key idea here is to use straight
plastic containers which has similiar size to, but larger, than the coin.

Put a brass coin at the bottom of the film can and place pellets "standing" on top of the coin. Place another coin on top of the pellets so the coin is flat and supported by
pellet heads. Repeat the "sandwiching" as you desire.

Now fill the container slowly with
"tap water", cuz tap water contain ions nescessary to ionize brass and lead.

Warm up the container and let it stay as warm
as possible, leave it overnight.

Next day the pellets should have been plated
with brass. Dry the pellets and re-lubricate them, they are now ready for use.

The result of improvement varies from brand to brand depend on the pellet manufacturer.
On one brand of pellet the author of the article claimed some 480 fps increase, while another brand only have 200 fps increase.

Proceed with caution since some countries have restriction on airgun velocity.

My notes: Brass sheets and large containers can be used instead of coins and film cans. The velocity increase come from reduced friction between brass "jacket" and bore.

This method is good because the plating is natural single replacement reaction and it will stop then the pellet is covered entirely
with brass. There is no need to worry if the plating has become too thick.

BEWARE OF LEAD POISONING.

2.Exploding targets

Co-invented with my friend. Place some HMTD powder between two pennies and sandwich
them, tape them together. Tape them on blank
paper. Start shooting.

My notes: We thought it didn't work at first, but actually we(well, I) missed the shot, when we tried again, it made a blast and send
the coins airborne. The coins are permanently distorted and cannot be used again. Gun used are just below 500 fps, where
our Canadian law permit.

BEWARE OF LEAD POISONING

3. Exploding airgun "plinkers"

A minor discovery of mine. Some firecaps are
loaded on a plastic strip instead of on a ring for toy revolver use. Those strip loaded
caps can be removed easily with hands. Firecaps of similiar size can be fired in .177 bore without problems. In my case, they are loaded from breech, flat nose facing towards muzzle.

The "plinker" is not accurate(hell no!) due to bad bullet shape, but will always make a pop when hit something, if bullet stumbling is not severe, 70% of chance you can see a jet of flash. (should try shooting in total dark.)

My note: You will see smoke in the barrel after taking a shot with this. What you see is lubricant present in the piston becoming aerosol, not that the kick of pressure loosen
the cap content.

I tried multi-charge the gun to make it a "plinker shotgun" but one exploded in the gun and I need to clean it right after.

Test gun is right below 500 fps. The plastic
"plinker" didn't ding walls but could penetrate about 20~50 pages of phonebook.

***Don't try to fire a firearm primer(or a projectile adapted a firearm primer) from an .22 cal. air gun, the primer is too sensitive and too short to stablize inside the bore and when it hits, the fragment can do serious harm(will pierce your eye and other bodyparts FOR SURE)***

BEWARE OF LEAD POISONING

4.Exploding airgun pellets

Invention of mine. Was struggling whether or not to publicize this but as long as you "sickoes" don't use it against human or some originally friendly dog, what the hell?

If you spend a day just looking at an airgun
pellet, after several hours you will start
to see illusion and hear things. One of the
things you will hear is the pellet saying :
"Oh I look like a tiny flask with a built-in
funnel, so put something funny in me and go out bust some rats."

It is important to choose the right brand of
pellet from the very beginning. You need pellets that is really similiar to "a flask with built-in funnel." There must be space
inside the pellet head, the opening of the funnel throat should be adequate.

***Wear eye protection during all this.***

a. Wash pellets with detergent to remove oil.

b. dry them.

c. load some HMTD powder into the "funnel"

d. tap the pellet on table so powder fall into the "flask" or head of pellet. Fill it
to right below the throat of the "funnel".

e. seal the throat with glue or vaseline.

f. wipe(recommended) or blow the pellet clean

g. re-lube the pellet.

h. fire the pellet at a hard surface for testing

In 20 meter tests, I have never recovered unexploded pellets. To prove it really explodes, I enclose the concrete surface with
a paper box and shoot at it at 10 inch range.

The impact sound is normal and there is no flash showing and no trace of unused explosive is visually seen.

The effect is interesting. The "skirt" is intact without any distortion, but the "head" is totally gone and became very tiny lead fragments (more than you can count in 20 seconds) found within
the box. I assume it is a success.

My note: If you are interested in using them against vermints, shoot the pellets at a block of soft clay first, if it didn't work,
either the range is inadequate, the gun is too weak, or the HMTD needs sensitizing, try
to blend HMTD with some fine sands.

BEWARE OF LEAD POISONING
BEWARE OF LEAD POISONING
BEWARE OF LEAD POISONING
BEWARE OF LEAD POISONING
BEWARE OF LEAD POISONING

By the way, did I mention
"BEWARE OF LEAD POISONING"?


sadsakjoel
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Posts: 170
From:
Registered: OCT 2000
posted February 08, 2001 02:52 AM
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I read that issue of airgun magazine, was it the one with the mountain bike dude?


HMTD Factory
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Posts: 217
From:
Registered: FEB 2001
posted February 08, 2001 04:26 AM
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Yep, I think that's also the one issue with
"airgun cartridge."
Yes it is, I found my magazine, wear and moisture have almost reduced the book into pulp. With the book at hand I should correct one error.

The maxinum increase the author had with one brand of pellet(.177) is 395 fps (810fps to 1205 fps) instead of 480 fps which I wrote, losing memory here.

And the least increase in velocity with a brand of .22 pellet is 204 fps (425 fps to
629 fps)

It's "AIR GUNNER" magazine, april 2000, page
57. With comprehensive and close-up photos.

In the maximum increase case, the velocity became about 1.5 of the original, that's roughly 2.2 times the muzzle energy of the original.

In the minimum increase case, the muzzle energy change is also close to 2.2 times.

While some serious American hunting magazines
are babbling about whether or not .270 Win is adequate for elk, British airgun magazines are taking people on "BIKE-HUNTING".

How shooting sports can be interesting really depend on what you do with your gun...I think, not saying that big game hunting is boring.


Microtek
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Posts: 194
From:
Registered: JAN 2001
posted February 08, 2001 05:19 AM
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If you want to make explosive pellets I have a method that will produce a more useable result:
First, use a soldering iron to melt a small amount of solder which you keep suspended on the tip of the soldering iron. Then use this to place a drop of solder in the "funnel" of the pellet ( you can also use epoxy, but then you must make sure that it will stick to the lead by sanding the inside ).
Now cut or grind the tip of the pellet off ( BTW, I'm assuming you use the pointy
pellets - if not, you may need to modify the process slightly ), and use a small drill to make a hole ca. 1.5mm diameter from the point, into the cavity in the pellet. Next step is to fill HMTD or AP into the cavity, and compress it using the blunt end of the drill-bit. Once the compacted HMTD is almost level with the point of the pellet, use some of the filler from plastic toy-caps to function as an impact initiator. It will be most reliable if you carefully mix this with a few iron filings. You shouldn't compress this, but simply cap the top with a bit of wax ( not candle wax, use something more sticky ).
The reason for pressing the HMTD is that it will be more resistant to the shock of firing, and more can be put into the pellet. Also, the DV is greater.
The use of the impact initiator is to ensure that the pellet will detonate even if it hits something soft, such as cardboard or flesh.


J
Moderator
Posts: 605
From: United Kingdom
Registered: SEP 2000
posted February 08, 2001 06:50 AM
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Another way of increasing the pellet velocity is to spray some WD40 into the compression chamber. On my cheap Chinese made .22, the difference is amazing :-) Before anyone decides to use petrol, be warned that the effect is much more powerful. A 'friend of a friend' did this, and the gun re-cocked itself from the force. At this power level, an exploding gun becomes a real possibility!
Another method for making 'exploding' pellets: Cap the funnel (skirt) with solder or epoxy, then drill a hole into the head. Insert a lighter flint into the hole, use glue to secure it. When fired at a wall, you will get a nice shower of sparks.

Just edited it to make a few things clearer and correct a typo.

J

------------------
"If the aquarium water has to be drunk don't waste the fish. In fact they'll probably be the easiest to eat even if you don't need the water. The cat is next in the pot." - John 'Lofty' Wiseman

[This message has been edited by J (edited February 08, 2001).]


Anthony
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Posts: 2312
From: England
Registered: SEP 2000
posted February 08, 2001 08:25 AM
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With these exploding pellets, do you guys mean to fil the skirt or the head of hollow pointed pellets? I assume that if you fill the skirt, then you fire them backwards, which would probably make accuracy suck.
I too use AP sandwiched between coins for exploding targets, those things fly off fast!

I'd be careful about using string solvents like petrol, you could end up with a dissolved piston seal. In theory diesel would be the best choice, since it is intended for compression ignition and would probably burn nice and cleanly.

I take it that brass coatings won't damage the barrel rifling? What makes brass such a good lubricant?


Mr Cool
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Posts: 991
From: None of your bloody business!
Registered: DEC 2000
posted February 08, 2001 01:47 PM
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If your rifle is a pre-charged pneumatic, try filling the air canister with helium at the normal pressure that you would use with air. This significantly raises the velocity of the pellet, because the helium stores the same amount of energy, but it's lighter than air. Therefore, more of it's energy goes into the pellet, rather than into propelling itself if you know what I mean.


Foodos
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Posts: 210
From:
Registered: SEP 2000
posted February 08, 2001 03:11 PM
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by 'funnel' you people are refering to the skirt right? (as anthony stated) then how is the accuracy going to be very high at all?
I remmember pyroboy made a post about melting some pellets together into a .177 cal brass pipe (or alum) to 'mold' his own, then he may have melted it to another half-pellet to obtain the skirt. why not do this with only 2-3 pellets, metl 2 together into a large 'slug' type pellet, and then using a saudering iron heat up one end, and the tip of a commercial pellet to 'weld' them together. then drill out the larger end of the pellet to fill with explosive/whatever, it would keep more accuracy having a skirt.


HMTD Factory
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Posts: 217
From:
Registered: FEB 2001
posted February 08, 2001 04:17 PM
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The explosive only goes into the head, the pellet is fired normally. In 20 meter test with a scoped rifle, accuracy is the same.
I didn't bother increasing the size of the pellet for more power, cuz if the head is too long, then it will not compress flat, will not likely to work reliably.

Remember, the explosive packed inside is loose powder HMTD, it is ignited by sudden compression, not because of the shock from impact.

If still obsessed with more power, experiment with a .22 cal. airgun, there is more room inside the head, but the velocity is slower.

Plastic pellets can be ideal for all you to
mess with since they are not toxic, easier to
modify( to mess with ) and although I have not seen them personally, I assume their wall
is made thinner cuz plastic are tougher than lead.

Melting lead to make big pellets? Unless you
are working on heavily customized ammunition,
you can order a bag of .172 25 grain hollow point bullets from Hornady or other reloading suppliers, save some work. (But again the slow rifling won't stablize heavier bullets)

"Dieseling" an airgun with caution, it is reported to cause receiver bulging and stock
cracking : pressure too high.

Not that brass is a good lubricant, lead is too soft and will "drag" and "smudge" in the bore.


Anthony
Moderator
Posts: 2312
From: England
Registered: SEP 2000
posted February 08, 2001 06:20 PM
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You can get plastic BB's called "plinklers", I wouldn't use them in a springer though becasue they weigh next to nothing and ca casue the piston to smack into the end of the compression chamber.
If lead is too soft, what about these new, all tin "Dynamic" pellets by prometheus? I've found them to give slightly better penetration but that's probably due to the fact they don't flatten so much.


HMTD Factory
Frequent Poster
Posts: 217
From:
Registered: FEB 2001
posted February 08, 2001 07:16 PM
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Lead is soft to a degree that you can write things with it on paper. When a pellet
is shot through the bore it leaves a rough
trace of lead on the rifling, it "fouls" the bore a lot.
Dynamic pellets have a relatively "straight wall" shape which contributes to higher
"sectional density" and thus the penetration
is better than original head-with-a-skirt design. Since they are made with alloy, the
performance of impact can be controlled.
They are better hunting rounds for that reason.


BoB-
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Posts: 651
From:
Registered: SEP 2000
posted February 08, 2001 07:41 PM
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"a flask with built-in funnel."
Hollow points?????
Is there any truth to the rumor that a drop of deisel in the pellets skirt increase's velocity?


vehemt
Frequent Poster
Posts: 580
From: Canada
Registered: SEP 2000
posted February 08, 2001 08:16 PM
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First off, good to see you HMTD Factory.
Using any kind of petroleum distillate in your air gun will ruin anything made of rubber, say o-rings. If methanol worked, maybe that could be used?

I found that shooting the toy plastic caps out of bb guns with as low fps as 280 with a .177 cal steel bb will still make them blow up on impact but accuracy is bad.

I used to load armstrong mix into the back of pellets binded with dextrin and wetted with 70% isopropyl alochol and let it dry with good ressults


HMTD Factory
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Posts: 217
From:
Registered: FEB 2001
posted February 09, 2001 01:57 PM
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Hi, Vehemt, good to see you again.
The .172 25 grain hollow point bullets are
originally firearm bullets, designed for
.17 remington and other .17 wildcats.

.172 and .177 have a difference of 0.005 inch
and that's about the thickness of human hair.


zaibatsu
Frequent Poster
Posts: 403
From: England
Registered: SEP 2000
posted February 09, 2001 02:21 PM
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OMG, i'm sorry to say this, but....
What month was the magazine published in? (April)

Why haven't any major pellet manufacturers thought of this idea before?

I think if you look carefully you will see this is an .... APRILS FOOL!!!

I too saw this issue, and am 100% sure that this is fake. Boy will i feel stupid if i'm wrong, but I incredibly doubt it. Sorry if I sound big-headed or arrogant, happy to see someone else was fooled too!

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Handguns don't kill people... Half as well as full-auto
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drake
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Posts: 60
From: london
Registered: DEC 2000
posted February 09, 2001 03:47 PM
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same here, i got pissed off, after i did it for the 10th time and no results, BELIVE ME its april fools, in the previous years issue they had an artical about a device that bred rabbits from embryo's, now that dident get passed me, but the pellat thing did, then i saw the month on the front and thought , stupid fucking me,
fake, thats all it is, think of it, why would they TELL u how to go over the limit, and give hooligans like us a way of further distruction


zaibatsu
Frequent Poster
Posts: 403
From: England
Registered: SEP 2000
posted February 09, 2001 04:55 PM
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Lol Drake, i was just going to post about that, that was pretty funny about the cloning machine, looked just like a set of small drawers, and then you saw the name of the person who wrote the article, lol
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Handguns don't kill people... Half as well as full-auto
Visit me at <a href="http://www.surf.to/eliteforum" target="_blank">www.surf.to/eliteforum</a>


HMTD Factory
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Posts: 217
From:
Registered: FEB 2001
posted February 09, 2001 06:07 PM
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I will personally verify if that is of fake information or not.
Drake, by trying 10 times do you mean the brass does not go on the pellet or it did go on the pellet but didn't make any improvement?

[This message has been edited by HMTD Factory (edited February 09, 2001).]


HMTD Factory
Frequent Poster
Posts: 217
From:
Registered: FEB 2001
posted February 09, 2001 08:11 PM
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The result of plating hasn't come out yet, so
keep waiting.
But I tried the explosive pellets in a spring gun, it mostly blow up in the gun, In one case the head leaves the bore but the skirt
is still inside.

Then I pushed the pellet inside the bore (with a short steel rod) for about 5mm deep to eliminate the resistance when the skirt engages the rifling by manually engaging it.
Then I put a small paper ball behind it to cushion the compression.

The loading is cumbersome but now the pellet work 100% of time. I did two tests with the pellet. One with an orange, one with a bucket of water.

The pellet exploded inside the orange when shot in short distance, but it didn't explode
when shot 90 degrees into water.

A clean entry hole is found on one side of the orange but a cross shaped breaking (1 cm wide, length and width) is found on the other side. After I cut the orange open I found the skirt is inside the orange with a wake of inch-long gray lead mark.
while the cross-shaped exit wound should be made by the exploded head leaving the orange at low speed.

Another find is that the pellet can be sealed
with dissolved smokeless powder (in acetone)
and left for drying, the dried film is durable and light in weight

Plastic pellets may be ideal because they weight less and will receive less kick from the compression, reduce the chance of pellet
exploding inside.

Test pellet is .177 7.4 grain round nose.


drake
Frequent Poster
Posts: 60
From: london
Registered: DEC 2000
posted February 10, 2001 04:40 PM
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i meant that i had attempted the experiment
10 times, with old style "high bronze" (their not)pound coins, and all 10 times, nothing happened
1 the mag does this sort of thing every
april as is attested to

2 as a starting-out metalagist i thought long and hard and it is IMPOSSIBLE for the migration from bronze to the pellet the metal atoms, it doesnt happen, due to the absence of a redox reaction (chemists,back me up) and so it isnt possible, what would be possible, is for the pellets to be electro plated with copper (from copper 2 sulphate) this i will explain if wanted, but it wouldnt give anywhere near the power boost of this "method"

and one fact , your air rifle cannot contraviene the conservation of energy law, as if it were to accelerat the pellet this much there would have to be NO FRICTION this means u could blow the pellat out of the barrel , let alone the power from the spring


HMTD Factory
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Posts: 217
From:
Registered: FEB 2001
posted February 10, 2001 08:56 PM
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Did you remove oil on your pellets?
Looks like mine are succeeding, but I kinda cheated, I dripped a drop of HCl in the water
to speed up the reaction.(HNO3 will be better
though.)

Metal content of the pellet is another factor, the purer the lead is the more likely
to succeed.

It is common case to lubricate the bore or the bullet to increase velocity, for instance
, Moly coating on bullet, Moly treating in the bore.

Moly treatment in the bore shrunk my 10/22
group by 40% at 25 meters.


Spudgunner
A new voice
Posts: 33
From: MO,USA
Registered: JAN 2001
posted February 10, 2001 09:29 PM
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Well, I plan on making an exploding pellet. What I have done so far is glue a primer onto the skirt of a pellet and glue some stiff piano wire into the hole and skirt. Then, i have a half inch length of .15" ID brass pipe i think it is that I am going to fill with flash (KClO4/Dark Al). Then I am going to glue that onto the primer with epoxy, making sure it is securly stuck to the primer. Then when the tube hits a wall, it will push the primer backwards into the wire that is glued to the skirt still trying to go forward. I dont know how effective this will really be, but I am going to make sure to tie a rope to trigger when testing it. Also going to do it at the farm or at night at house when parents are nowhere close. Dad might not like exploding pellets. It looks like overall length will be about 3/4" so i will have the gun close to whatever I am shooting at so stability wont be a real problem, although if it his bass-ackwards it should still go off, if not better. It should be interesting, and if I make a couple I might have to try to hit a rabbit. Dont know if the tube will even explode, or if it will separate my fairly strong bonds. I can always hope parents leave home for a while so I can test it so I dont have to wait for next trip to farm.

The_Rsert
December 8th, 2004, 05:59 PM
I have a new 1.0 joule airsoft gun (Modell M16 A4) :) an an old but very good 4.5mm "Diana" airgun :)
I have just shot of <500mg diacetonetriperoxide in my room with the softair-gun and a 0.20g bullet.
Kaboom! This was one of the loudest "little" detonations, I've ever had.
Of course, this will work also with the airgun and outside.
:) :) :)

nbk2000
December 8th, 2004, 08:12 PM
Was the AP in the hollow air-soft bullet, or shot out the barrel as a melt cast slug, or what?

good1
December 14th, 2004, 02:30 PM
You can buy copper coated pellets,I got some recently to try compared to my lead although on the tin it just says for extra hardness.Recently read a book on airguns and dieselling(Explosion of vaporised lubrication due to compression from the spring piston).Adding lubrication into the transfer port does increase velocities but can damage your spring/break it.

Jacks Complete
January 9th, 2005, 09:44 PM
Adding oil to the back of a pellet is called "dieselling" since the rapid heating from the air causes the oil to burn, and power the pellet out fast, just like in a Diesel engine.

It will rapidly destroy most air rifle types, causing a loss of accuracy when not being dieselled. Never try it in a pneumatic gun! They can't take the back pressure on the valve. Only use old spring guns.

Also, use the heaviest pellets you can find, and tiny amounts of oil to start. You will find that you can get the pellets to fly apart and go supersonic, even with small amounts of fuel.