Rifle barrel for spudgun

Potatoes last one shot, so build reusable! Discuss ammo designs and ideas. Tough to find cannon part or questions? Ask here!
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Ragnarok
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Mon Sep 22, 2008 6:46 pm

@JSR: It still seems a little disappointing.
We know that .177" and .22" air rifles with similar muzzle velocities can yield good results at 50 yards, thus proving that slow doesn't have to be inaccurate.
I know something like the Exile would have a longer lock time than a powder burning .308, which would tend to increase group size, but with good shooting practises, it shouldn't be that significant.

Logic says that it should be able to yield better results, but it clearly doesn't.

Perhaps the problem comes from it's incredibly high air consumption (and thus erratic muzzle velocity) and barrel/chamber supports shifting the barrel as the chamber moves with pressure changes - a problem that is exacerbated by the air consumption.

I wonder what could be had out of it if it could be regulated and had a free floated barrel...
Does that thing kinda look like a big cat to you?
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Mon Sep 22, 2008 11:20 pm

If you take a look at what Gary Barnes does with his big bores, tighter groups are of course possible - but, again, for the purposes of the Exile, essentially "unecessary".

If you're shooting small birds like one would do if one were hunting with a 12 ft/lbs airgun, a 1" group could mean that a guaranteed hit to the vitals was not reliably achievable. However, for the sort of game these larger rifles are used for, even a 4" group at 50 yards pretty much assures that what you aim for is going down.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Ragnarok
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Tue Sep 23, 2008 6:52 am

jackssmirkingrevenge wrote:but, again, for the purposes of the Exile, essentially "unecessary".
Unnecessary maybe, but I wouldn't ever be rushing to buy a rifle unless I was sure it could outshoot me - but that's really because I'm a target shooter.

When I want more power, I call on my launchers - and it's possible that if I ever buck my ideas up, I'll manage the the long range darts and get accuracy out of them as well.
Does that thing kinda look like a big cat to you?
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jackssmirkingrevenge
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Tue Sep 23, 2008 7:09 am

Horses for courses - get yourself a bespoke Air Arms and poke holes in paper while *real* airgunners take some proper meat home ;)

Just kidding, of course, I see your point, but we don't all demand the same parameters from our rifles.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Ragnarok
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Tue Sep 23, 2008 7:34 am

jackssmirkingrevenge wrote:I see your point, but we don't all demand the same parameters from our rifles.
Indeed, we don't, but in this country, where we're only allowed 12 ft-lbs, I've developed the opinion that accuracy is the most important feature.
I know I'm being a bit hypocritical, myself being the owner of a springer, a less costly, but less accurate solution (much like the Exile).

I suppose its the old European/American mindsets again. Europeans trying to get the most out of the least, and Americans just making it bigger instead.
Does that thing kinda look like a big cat to you?
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Wed Sep 24, 2008 12:01 am

Accuracy is equally as important as power IMO. No use having 1000 ft.lbs if you can't hit anything. Equally as frustrating, being able to hit the target, only to watch your shot bounce off.

The right "mix" for the job at hand is always what is best.


I suppose its the old European/American mindsets again. Europeans trying to get the most out of the least, and Americans just making it bigger instead.[/quote]

I'm not so sure about this, the first large bore airguns (.32, 9mm and .50 cal) I ever saw were creations of John Bowkett. From your side of the pond I do believe? :)
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Wed Sep 24, 2008 3:53 am

Gippeto wrote:Accuracy is equally as important as power IMO. No use having 1000 ft.lbs if you can't hit anything. Equally as frustrating, being able to hit the target, only to watch your shot bounce off.
In hunting terms both parameters complement eachother. In the case of an accurate but low-powered rifle, you have the option of accurately hitting a vital area that will bring your quarry down. In the case of a less accurate but more powerful rifle, you can aim for a larger target (for example the chest instead of the head) and still know that your slug has enough grunt to do the job. This is the case with the Exile, so in terms of what it's designed to do, it's an excellent rifle :)
I'm not so sure about this, the first large bore airguns (.32, 9mm and .50 cal) I ever saw were creations of John Bowkett. From your side of the pond I do believe? :)
The first big bore air rifles (and indeed, the first precharged pneumatics) were definitely European, but they date back to a little before the time of Mr. Bowkett ;) In true European style, the Girandoni and its kin were not only powerful and accurate, but also remarkable efficient :D

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Of course this American 20mm monster takes the cake, not sure how many shots per fill though :roll: :D
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Wed Sep 24, 2008 6:29 am

Gippeto wrote:I'm not so sure about this, the first large bore airguns (.32, 9mm and .50 cal) I ever saw were creations of John Bowkett. From your side of the pond I do believe? :)
It's not a completely hard and fast rule, it is just a generalisation - but it does apply reasonably often, mostly in car design.
Does that thing kinda look like a big cat to you?
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john bunsenburner
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Fri Oct 24, 2008 4:30 am

you can make simple pellets by getting a drill bit and grinder(you know the things with the rotating disc not some kinda hot girl) then you make the drill bit the shape of your pellet but remembre that you cant make some fancy stuff, just like making the end sharp or sumthing. theny you drill some holes into a piece of metal with a meltng point higher than that of lead or tin or what ever you are using. saw the metal in half exactly where you drilledy your holes so each hole is perfetly cut in half(ok it doesnt have to be perfect. and yes you have to line the holes up in one strait line!!!) attach a hinge at the bottom and some kind of lock on both sides. if you are intelegent you can make the holes a bit deeper and put some kind of funnel shaped crater above them so that the lead will acctually go into the hole. when you are done you will have a simple pellet mold for pretty much any metal with a melting point below 800°C(if you used the correct metal for the mold)

p.s. lead,tin and zin can all easyly be melted with a small propane or butane camping stove.

p.p.s if you dont understand private message me ill send you some pics and explain in more detail. maybe ill put up a post about this some day!
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Fri Oct 24, 2008 7:59 am

The above will only work for rifled barrels though, for most spudguns with a smooth bore you'd want a mandrel to ensure a hollow tail for stability (or drill it after casting) - like a shotgun foster slug:

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hectmarr wrote:You have to make many weapons, because this field is long and short life
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Tue Oct 28, 2008 7:35 pm

Get yourself a muzzle loading barrel, cut the threaded breech off and shoot roundballs, the muzzleloadin barrels have a twist rate designed for lower velocities, although you may still wnat a faster twist rate ie 1-48 or 1-24 even.
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