PDA

View Full Version : Cast Boolits for Spring Power Air Rifles?



longbow
11-04-2013, 01:15 AM
Are there any .22 or .25 cal. spring/gas ram powered air rifles that are capable of shooting cast boolits... at least at reasonable velocities?

Or is that the domain of the PCP guns?

Looking to get a .22 or larger air gun and wanting to cast for it but not necessarily wanting to jump into PCP with all the "stuff" to get for them.

Just curious.

Longbow

HollowPoint
11-04-2013, 11:19 AM
Hi Longbow:

What do you mean by "Reasonable Velocities?" It seems that few air gun actually achieve the velocities listed by their manufactures. Those that do have to be tuned in order to come close to achieving their touted velocities.

Most of the PCP air rifles I've looked at list 1000 FPS with the lighter weight lead conventional pellets. With the heaviest commercial pellets like 18-21 grains that velocity goes down to the mid to low 700 FPS or less in their out of the box configuration.

I've only come across one Gas-Spring air rifle that has a listed velocity of over 1000 FPS; it's the Umarex Octane in 22 caliber. In theory, this particular Break-Barrel Springer should keep up with the PCPs. If everything goes according to plans, I should be ordering one within the next couple of days.

I agree with you about the PCPs. I'd love to own one but, I hate like heck having to buy all the peripheral equipment needed just to get it to shoot. (Pump, Air-Tank, Regulator, scope, etc.) I've been there and done that before. It can total up to a hefty price tag. I particularly like the Benjamin Marauder line of PCPs.

With this Umarex Octane I plan on tuning it myself. I have a few ideas that I've garnered from working on other air rifles. Also, I too have been looking into casting my own projectiles. I don't think it would be that difficult; provided you find or design a bullet that's light enough. (20-30 grains) Custom aftermarket 22 caliber pellets tend to be straight walled bore-riding configurations but, the friction that these designs have still make them slower than the wasp-waisted shuttle-cock designs of conventional pellets of the same weights. Down range velocities and energy are improved but, I think it could be better.

With break-barrel springers, I think you're on the right track as far as wanting to cast your own. I hope you find what you're looking for. When you do, please let us know. If you come up with a good aftermarket design, definitely let us know.

HollowPoint

grizzlyadams
11-04-2013, 12:14 PM
the umarex octane only achieves that velocity with ultralight alloy pellets. with a 14 grain lead pellet, you are going to be at more like 900fps. the octane is just a xisico b28, which i a clone of the rws 350. then them modified the trigger group so it could accomodate a gas ram instead of a spring. also, umarex is notorious for grossly exaggerating real world velocities, they test the gun while it is dieseling, and add 10%. gamo and crosman do the same thing. none of these guns shoot as fast as claimed. the only company that tests with lead pellets to get velocity ratings is hatsan. their models 125 and 135 are about as much power as can be had in a breakbarrel. the 25 caliber consistantly put out 30+ ft lbs

rattletrap1970
11-04-2013, 12:20 PM
Beeman and MANY other lie about their velocities (lies of omission of information) they claim high velocities but only achieve them with the lightest pellets available on the market or using their own uber-light pellets. I have found that most PCP rifles (pre-charged Pneumatics) give a lot more information regarding velovities over a wide range of pellets. Some of the larger PCP rifles are quite capable of shooting cast boolits (cause after .25 caliber I just cant call em pellets anymore) at velocities velocities that allow effective hunting of medium sized game at typical hunting distances.

grizzlyadams
11-04-2013, 12:59 PM
correct on the pcp thing they usually do not rate them with alloy. as far as the springer/ gas ram and cast. most of them are not going to have the power to push anything heavy. you are talking a max of about 20 or so grains for 22 and about 30-35 for 25 cal

MT Chambers
11-04-2013, 03:36 PM
The cast boolits will be very slow if my exp. is any indicator, the Wolverine fires a 51 gr. 30 cal. pellet at 960 fps, which is a powerful PCP and gets 12 full power shots to a fill.....the 80 gr. cast bullets drop that velocity to 761 fps......so I would imagine that springers would be very slow with cast bullets any heavier then pellets regardless of caliber. In the case of the PCPs, you want them to produce good velocity AND an acceptable amount of shots to a fill, so you can take it out in the field. Results with my AA S510 in .25 cal. are similar except for a much increased shot count at the expense of lower velocity. I will experiment with a very accurate Daystate Huntsman XL in .22 cal. with cast this winter. I will also experiment with a Daystate Air Ranger .25 with 80 fpe, with cast bullets ,when I am in Europe.

rattletrap1970
11-04-2013, 03:56 PM
I have an RWS Model 52 in .22 caliber. I have some Beeman Kodiak pellets that are 21gr. I will wing a couple over my chrono and let you know what they come out at.

HollowPoint
11-04-2013, 06:15 PM
Have any of you guys with a 22 cal PCPs ever tried the 30 grain PileDriver projectiles or the heavy aftermarket pellets that the bulletsmith sells?

I just ordered my new 22 cal today. It should be here by the weekend. I can't wait to start playing around with it; I hope I don't have to tweak it into living up to my expectations but, deep down I'm thinking I'll have to do just that.

HollowPoint

MT Chambers
11-04-2013, 06:48 PM
I tried most everyone out there in my .22 and the JSB 15 and esp. the 18gr. were best, but I think that a heavier pellet has a better chance of success, then cast in the .22, and besides .22 cal. pellets are not that expensive!

HollowPoint
11-04-2013, 07:44 PM
"Besides .22 cal. pellets are not that expensive!"

I've heard that alot since looking into cast bullets for a 22 cal air rifle; and I know it's generally true but, my psychological makeup forces me to try to improve on things that are generally fine just as they are. It's a malady I've suffered from since I was in elementary school.

I couldn't begin to count how many toys I've damaged or ruined trying to improve them in some way or other. Fortunately, if I did break them I was able to fix them.

On a bright note; the things I did manage to improve turned out to be a real joy to play with. I'm believing for the best with this new incoming toy. I've thought of turning some brass projectiles with better aerodynamics on my lathe just to see how they shoot.

It doesn't hurt to try.

HollowPoint

longbow
11-05-2013, 12:50 AM
Well, I guess that sort of answers my question.

Not looking for blazing velocities over 1000 FPS with these but more like 800 FPS.

What I was thinking about was a .22 with lightweight Hornet boolit like the 225107 but even that is 37 grs. or a .25 with a boolit like the 257420 which is 65 grs. Both probably too heavy for spring or gas ram systems then.

Like HollowPoint, I like to do it myself and casting is fun.

.22 would be a little small but .25 cal. round balls might even keep me occupied and interested. Those would only weigh about 25 grs. so might be doable. Any comments there? Other than that round balls shed velocity fast. I suppose rifling twist/accuracy might be an issue too.

I see that Beeman Kodiak extra heavy pellets are 31 grs. so a round ball is in the ballpark.

Just toying with ideas.

If anyone has tried something like this I would like to hear about it, good or bad. Hmmmm, especially the bad so I don't waste time and money.

In the end I will probably wind up saving for a PCP + peripherals to keep it going.

Thanks,
Longbow

Lead Fred
11-05-2013, 01:29 AM
I'd like to find a 20 cal (5mm) mold.
I'd use the pogees out of it

HollowPoint
11-05-2013, 10:49 AM
I know that .22, 20 and 25 calibers are the most popular of the PCPs but, If I ever got to the position where I could afford to buy one of these air rifles and all the need peripherals, I'd really think seriously about re-barreling and re-chambering to a slow twist 6mm/.243; especially if I'm casting my own projectiles.

I don't know why the air gun manufactures skipped over that caliber. I suspect that due to sectional density differences of similar weight bullet-shaped projectiles, it might be easier to get to shoot well with heavier projectiles than the traditional air rifle calibers; or pellets for that matter.

HollowPoint

grizzlyadams
11-05-2013, 11:02 AM
the round ball would be light enough, and one of the more powerful guns , like the hatsans will push 25 grains along at about 750fps. if you can get them to seal right. the most powerful of the three hatsan 125 (29mm piston, 120mm stroke)that i tuned, which was for my brother in law. cranked a 31gr baracuda out at right at 700fps. which is smoking hot for a piston gun at almost 34ft lbs. and was weird because i was looking to smooth it out, not beef it up, but it shoots well, so no complaints. you wont see much more out of a gun of this type.some guys have been tuning the hatsan 135, which has a bigger powerplant (30mm piston with a 120mm stroke) to a bit higher, but i cant see them lasting long.one in particular that i have been watching is tearing the guns down every couple tins of pellets to "freshen " it. that to me is counter productive.i think piston guns are best served in .22 caliber and not run maxxed out, for best efficiency and shootability. not to mention longevity..25 caliber really starts to shine when you get up into the pcp guns, and over 40ft lbs.anything under that, and i will take a .22 any day. flatter shooting and better penetration on game. not to mention ammo choices.for the piston guns it is best to just stick with pellets. cast boolits are for the pcp pneumo blasters

rsterne
11-05-2013, 01:05 PM
I would agree that for the most part, sticking to pellets is the better route for springers / gas rams.... for one thing, they basically have no chamber, just a slight bevel on the breech to accomodate the oversize pellet skirt.... You would have extreme difficulty even chambering the proper sized bullet in most springers.... What the actual caliber is, is a problem as well.... .22 cal airguns are 0.217" and .25 cal are 0.250".... whereas .22 rimfire bullets are 0.222"-0.223" and cast bullets for PBs run 0.224-0.226".... so basically you have to beat them into the barrel (not recommended!) unless you size them down, and that is a long way to size them.... There is only one mold in .25 cal I am aware of, the RCBS #57902 which drops a 50 gr. RN for the .25 ACP pistol at about 0.251".... All the other molds I am aware of are 0.257", again too far to really consider sizing them down to 0.250"....

You could have a custom mold made, of course, of the proper diameter for an airgun barrel.... You would have to look at the twist and make sure the bullet isn't too long and would be unstable.... The Border Barrels (Scotland) website has an excellent calculator you can use for that.... http://www.border-barrels.com/barrel_twist.htm

The next question is "how heavy" is reasonable for your particular gun.... Basically, in a springer / gas ram, the FPE will stay relatively constant (unless you go really heavy) so you can just convert your current FPE into a velocity estimate by reversing the FPE equation:

Velocity (fps) = sqr.rt (FPE x 450,240 / weight) .... For example, if your gun shoots 30 FPE and you want to find out how fast it will shoot 35 gr. pellets....

30 FPE x 450,240 = 13,507,200 .... 13,507,200 / 35 gr. = 385,920 .... take the square root and you get 621 fps....

PCPs will generally shoot a bit higher FPE with heavy bullets, so you can figure you will exceed what you calculate by maybe 10%.... Springers / gas rams may well lose FPE with very heavy bullets, so you may not achieve what you calculate.... There is also a chance you will damage the spring if you go too heavy....

Bob

HollowPoint
11-05-2013, 04:31 PM
We shall see.

I've read a whole lot of write-ups and viewed as many videos as I could find regarding the Gas-Ram gun I'm waiting to arrive. Some of these write-ups and some of the videos generally agreed with what some here have posted. Others did not. It's kind of like conventional firearms; even with guns of the same kind, some of them exceed expectations and some of them fall short of expectations.

Since this Gas-Ram Springer break-barrel is relatively new to the market in its Umarex configuration, the jury is still out on it. We can extrapolate based on similar designs but in the end, I think it's going to take a hands-on approach to really see what this gun can do.

Extrapolating, in this case is just like Assuming. It's a good starting point but it has no bearing on the real outcome; especially if a guy plans on tuning it wether it shoots good or not.

HollowPoint

ThomD
11-09-2013, 04:51 PM
You can apparently make pellets in a standard reloading press. Corbin made dies. All that is probably too expensive for most, but I did wonder how much progress one could make with a simple set up if one had a lathe etc... But yeah pellets are cheap.

W.R.Buchanan
11-09-2013, 07:24 PM
longbow: there is a style of pellet that you could conceivably cast. It also lends itself to being swaged.

There is a good blurb on these things at the Corbin Website.(Bullet Swaging Equipment suppliers.in Oregon no less)

Apparently pellets work exactly like shotgun slugs when they fly. IE Lyman 525 gr slug that looks like a giant pellet.

A pellet that looks like to older style Sheridan Pellets, essentially a cylinder with a round nose on one end and a small skirt with a hollow base on the other. the pellet is essentially a 'Bore Rider design, " with the skirt being the only thing that takes the rifling. It has to be nose heavy to fly right and thus the hollow base design. Just like a shotgun slug.

As far as Swaging the pellets is concerned it would be the best way to do it simply because you are going to get a real precision product. At around $400-500 for the complete set up to run in a Rockchucker press, you'd have to shoot up around 10,000 pellets to pay for it.

The die is adjustable so you can vary the weight by about +/- 5 grains IE 22 gr +/-5.

My R1 shot a 22 gr H&N round nose pellet nearly 1" into a dry phone book at 50 yards.

As far as making the die it would be a trial and error type of thing. The Corbin dies are made by die makers that actually know what they are doing and they are made to last, IE; right materials, right tolerances on fits between parts, bleed holes so very lead blank doesn't have to be exactly the same weight and heat treated to last. In other words they are actually worth the money you pay for them, you just have to get the use out of them to make it a cost effective solution.

That means shooting a lot! And there are several people here who do shoot that much. When you hear 2500 rounds in a month, that is someone who is dedicated! In their case this tooling would justify itself in 4 months. In my case more like 2-3 years.

A mould for this type of pellet could be easily made, by one of our boolit mold makers for less than $100 I think. Then you would have to shove it into a sizing die that brought it to the correct size for your gun, and effectively "Swage it to size." This could result in a pretty consistently sized product, but it is never going to be as accurate as a swaged Pellet.

You can buy a lot of pellets for $500.

Randy

Wally
11-09-2013, 08:05 PM
That sure is the truth....an RWS34 .177 is supposed to get 1,000 FPS...I used a 7.0 grain pellet and it gets a bit more than 800 FPS. There model 24 is rated at 700---I get 555 FPS... I am amazed as to how much they lie about it...



Beeman and MANY other lie about their velocities (lies of omission of information) they claim high velocities but only achieve them with the lightest pellets available on the market or using their own uber-light pellets. I have found that most PCP rifles (pre-charged Pneumatics) give a lot more information regarding velovities over a wide range of pellets. Some of the larger PCP rifles are quite capable of shooting cast boolits (cause after .25 caliber I just cant call em pellets anymore) at velocities velocities that allow effective hunting of medium sized game at typical hunting distances.

longbow
11-09-2013, 09:33 PM
Randy:

I have thought about the "trash can" style pellets and they are very similar to my latest hollow base shotgun slug waiting to be tested... except they are a wee bit smaller.

My thoughts exactly. I can make a nose pour hollow base mould which is what my shotgun slug mould is but I would have to swage the little sealing edge on the skirt.

Someone posted a video of a fellow in the UK making pellets of that style using a cast core and hammer swager. The mould looked a little crude and didn't have handles but all in all it seemed to turn out a decent product.

I think I could make a mould down to maybe .22 cal but .25 or larger would easier.

Longbow

HollowPoint
11-10-2013, 11:55 AM
That Umarex Octane air rifle I ordered came in on thursday. I took it out of the box and cleaned out the bore just before I took it outside for its first several shots.

It shot way slower than the stated velocities on the box; WAY slower.

After looking it over I found that the Little Rubber O-Ring Seal at the breach had been permanently crushed flat by the "Quick-Tips" card that the manufacture squeezes into between the breach and the air chamber. I guess they do that so that a new buyer will be sure to look at it.

Unfortunately this "Quick-Tips" card is thick enough to permanently flatten out that little O-Ring and thereby cause enough gas leaking that the velocities of any given pellet weight are adversely affected. A quick trip down the street to my local hardware store for a new replacement O-Ring and that problem was solved. Even with the new O-Ring I still wasn't getting the velocities stated on the box but, I did see an increase in velocity that averaged around 32 fps according to my chronograph.

The trigger on this rifle is an adjustable two stage trigger. It felt more like a 5 or 6 stage trigger due to all the grit I felt as I pulled back until it fired. Any adjustments are strictly for the first stage of the trigger pull. It does nothing for the important part of the trigger pull; which is the part that actually releases the sear and fires the gun.

I couldn't help it. I had to take it apart and take a sharpening stone to the part of the trigger components that smoothes out the second stage of this trigger. I have no way of measuring the amount of pressure it takes before the trigger breaks. I can only go by feel; and it feels much, much better now.

I also ordered one of those NOE 22 cal 37 grain bullet molds. Since I'm generally trapped indoors for now due to allergies, I may be able to experiment with different configurations of this particular cast bullet in the upcoming week.

It's a three cavity mold. I plan on hollow pointing one of the cavities and leaving the other two as they are.

If things work out with these little cast projectiles I'll let you all know. I hope to try casting Hot-Melt-Glue bullets and trying those, then I'll try hollow pointing them to see how they fly compared to the solids; after sizing them down to the proper size of course.

Forgot to mention; I did a chamber cast on this new air rifle. There is no real chamber to speak of; it's just reamed out ever so slightly at the mouth of what would be called the "Chamber" on a conventional firearm.

I got a measurement of .2197" at the mouth and .2185" at the distance where the head of JSB 18.13 grain pellet head goes to the depth of.

With these measurements I can now make up a swaging die for an exact fit of these cast bullets into this air rifle's chamber. After casting I can swage them into the correct shape and diameter. I'm still not sure if the twist on this air rifle is enough to stabilize this slightly longer cast bullet. I'll find out soon enough I guess. If I have to I can also swage it down to a slightly shorter bullet.


HollowPoint

longbow
11-10-2013, 12:52 PM
I will be anxiously awaiting range reports or at least indoor shooting reports... whatever you get done!

Longbow

W.R.Buchanan
11-10-2013, 02:11 PM
Longbow: I can make the mould, however it will probably be a trial and error type of thing since getting it to turn out he right size, net, is going to be nearly impossible.

The sizing die would not be hard either, but it would be a trial and error thing as well.

This is the type of thing I will do after I retire since I can't justify taking time away from paying jobs to make this type of stuff.

I do have a long list of things I intend to make as products, but until the Navy kisses me goodbye, they will all be on hold.

Randy

HollowPoint
11-10-2013, 05:11 PM
I found my recently ordered NOE 37 grain 22 caliber mold in my mail box this morning. I guess it had been sitting there over night.

Since it's Sunday today and I really didn't have anything else planned I decided to cast a few Hot-Melt-Glue bullets with it just to see what I came up with.

I made up a handful and to my surprise they dropped from the mold at just a tad under .22".

I knew they'd be alot lighter than their lead counterparts but, I didn't think they'd be as light as they were. Most weighed only 4 gains with a small percentage weighing only 3.5 grains. I figured those lighter ones had air bubbles in them.

I'm kind of hoping that when I cast up a few out of Stick-On Wheel-Weights they'll drop from the mold at the same .22". That will mean I won't have to size them down as much for initial testing.

It's looking like I may not be able to test them in my back yard as I'd hoped.

I'm not really afraid of not having a heavy enough back stop. I'm thinking that these heavier projectiles may carve their way through my backstop in pretty short order with these higher BC bullets. Conventional pellets don't go any farther than the surface of my backstop after they've gone through the initial 18 inches of foam I have set up.

I'm going to have to come up with some kind of Quiet Backstop because even my conventional pellets let out a rather loud smack when they finally reach the wood face of my backstop.

I couldn't resist shooting at least one of the Hot-Melt-Glue bullets over the chronograph. Since they're so light weight I was kind of afraid it would be similar to dry-firing my gun but, I figured just one shot wouldn't hurt.

Talk about Sonic-Crack; it scared the freaken-Sh!!!+ out of me. I won't be doing that again any time soon. At least not in my back yard. I should have known better.

That little 4 grain Hot-Melt-Glue bullet had a muzzle velocity of 1579 fps. My backstop was only 15 yards away but, the loudness of the shot caught me completely by surprise. It's a good thing I was situated well below the tall slump-block fence of my back yard.

I definitely heard it when it struck the backstop but, I don't think that little Hot-Melt-Glue-Bullet hit where I was aiming cause I couldn't find any sign of it at my point of aim.

I use old seat-cushion-foam as my initial backstop with about 6 total inches of stacked plywood directly behind it. I scoured that backstop from top to bottom and couldn't find any sign of my Hot-Melt-Glue bullet. My backstop measures about 8 feet tall and four feet wide. It's chipped and dented with countless other pellet strike-holes all over it but no sign of the Hot-Melt-Glue bullet.

Either it completely disintegrated or it came to a stop inside one of my foam cushions. I'll test these out again once I'm able to get out to the desert or the shooting range.

It only took that one shot to determine that it's way to dangerous to test any more of these in my back yard.

An interesting side note about these 4 grain Hot-Melt-Glue bullets; I ran them through one of the online ballistics calculators and came up with the following numbers. I'm not sure what the actual BC of this bullet is at these velocities so I entered .100. I'm pretty sure it's higher than the highest BC of your over the counter air rifle pellet. Still, you need to take this with a grain of salt. (also worth mentioning; I got no Hot-Melt-Glue fouling in my bore.)

Muzzle Velocity= 1579 FPS Muzzle Energy= 21.6

100 Yard Muzzle velocity is still Super-Sonic= 1393.5 FPS Muzzle Energy=17.25

I'll be back with updates when I'm able to get out and about again.

HollowPoint

longbow
11-11-2013, 01:57 AM
Those glue boolits look very nice! Well done!

I just may have to try that too.

Longbow

rsterne
11-11-2013, 06:56 PM
To calculate the BC of a bullet you need to divide the Sectional Density by a FORM FACTOR.... The BC for a 37 gr. lead bullet will be 10 times higher than the BC for a 3.7 gr. glue bullet of the same shape (and therefore same form factor).... so your BC will more likely be about 0.010.... NO WAY that bullet is going to stay supersonic for long.... about 25 yards, tops.... assuming it was still in once piece, that is.... At 100 yards it will be down to about 450 fps and less than 2 FPE.... Sorry....

Bob

MT Chambers
11-11-2013, 07:54 PM
I'm watching this closely as well, want to see what the final dia. is of boolits, and whether the throat had to be changed to facilitate loading.

HollowPoint
11-11-2013, 08:40 PM
By changing the BC from .10 to .01 the estimates given by rsterne are about right on the money. With these Hot-Melt-Glue bullets I didn't have any problem getting them to chamber. They were snug but they went right in.

I'm still going to test them at ranges longer than 15 yards; just to make sure the online calculator was anywhere close to correct.

I had a slow work day today so I cast up about 50 of these little pills out of Stick-On Wheel Weights. It's as close to pure lead as I can get.

They dropped from the mold at a diameter of .2245" and .225." The average weight with this type of lead was closer to 39.5 grains than it was to 37 grains. If I were using Clip-On Wheel Weights or some lighter lead alloy I think it would have come closer to the 37 grains this mold is listed at.

I did manually hollow point one of these lead cast bullets just to see how deep of a hollow point I'd need to make in order to bring the weight down to 30 grains or less. I'm happy to report that it looks as though it's well within the realm of possibility.

It looks like I'm going to go ahead and hollow point all the cavities instead of just one of them. I can set it up with reversible pins so that I can use this same mold for my air rifle and my 223 center fire if I were so inclined.

I'll be turning my new swaging die within the next few days. I need it in order to swage my hollow pointed bullets down to the dimensions I got off of the chamber-cast I made. I figure that with the hollow point being as deep as I'll be setting it, when I swage them to final dimension, rather than shearing off lead from the outer surface of my bullets with a sizing die, the hollow point cavity will allow me to compress them down into shape instead, without losing any depth in my lube-grooves. (I hope)

I'm fairly sure it will all work out. I just have to take my time when I do this work. I tend to get into a hurry and that's when I run into problems.

HollowPoint