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HollowPoint
01-10-2015, 07:23 PM
I'll Never Have To Buy Pellets Again !

Since I got a couple of days off during the holidays, I finally got the chance to try my hand at making my own .22 caliber pellet swaging dies. As is usually the case when I do a project, my first attempt missed the mark in terms of diameter dimensions. The actual die turned out good and functional but I had measured my bore incorrectly using some Cerrosafe to make a chamber-cast.

These pellets wouldn't even load into the chamber. They were .004" to big so I made a push-thru sizing die to bring them down to the right diameter. This too worked out well however, the finished pellets weighed from 25 to 28 grains. This was much to heavy for my Break-barrel Umarex Octane air rifle.

The 14-point-something grain and the 18-point-something grain conventional pellets have always shot extremely well out of my air rifle so ideally I was wanting to make a finished pellet that came in at similar weights. To control the weights I made an adjustable five cavity cylindrical hollow pointed lead slug mold. By screwing the hollow pointing pins in or out I could control the weights of the slugs and thereby, the weights of the finished pellets with a minimum of trimming.

I'm not a machinist and I suck at math so all of my projects are tackled via the Trial-And-Error method. After four different attempts at getting my dies to spit out the right sized pellets I then started with the tweaks to get them as close to perfectly symmetrical as possible; followed by chronographing and accuracy testing.

I always wondered why, with all the cutting edge advances being made in the air gun field, none of the air gun manufactures ever seemed to give any attention to upgrading the design of the ammo that air guns shoot. Think about it; thousand-plus dollar cutting edge PCP and such, shooting first generation wasp-waisted, shuttle-cock pellet designs. It just seemed to me to be like a state of the art fighter-jet being pulled along by a propeller driven engine.

To that end, I thought I'd try a different, more ballistically streamlined pellet profile. To do that and still be able to let my new pellets be long enough without being to heavy for a low powered Gas-Piston break-barrel air rifle, I had to make these pellets in the Bore-Riding Hollow-Core design. This also leaves enough of a Bore-Riding section to stay centered in the bore as it's moving toward the muzzle.

Velocities are in line with conventional pellets of the same weights. Accuracy thus far is continually increasing as I figure out the nuances of using these new dies. I discovered that if I spin the die as I'm swaging my pellets, they seem to come out more concentric and more accurate on target; as well as weight-wise. I'm able to get them to within .3 grains of each other. Even my tin of conventional first generation pellets don't all come in that close to one another.

I also made a tail forming pin that allows me to shape the tail ends into a Rebated-Boat-Tail but that iteration still needs some major tweaks to get it to form concentrically. It may take a whole new project to get the Boat-Tailed pellets to fly well.

I'll post pics a little later. In the mean time, I couldn't withhold my excitement with this project. I have two five gallon buckets full of discarded Stick-On Wheel-Weights that represent a life time pellet supply.

I'll be back when I get my photos edited.

HollowPoint

alrighty
01-10-2015, 08:14 PM
Congratulations!!! It sounds very interesting to say the least , I would love to see some pics.

HollowPoint
01-10-2015, 08:17 PM
Wow. Perfect timing. I just posted the first pic of these pellets.

HollowPoint

koehlerrk
01-10-2015, 08:45 PM
British company is doing something similar... watch this and see if their design gives you any ideas...

https://www.youtube.com/watch?v=fAMSWqJxQ3Y

HollowPoint
01-11-2015, 11:40 AM
British company is doing something similar... watch this and see if their design gives you any ideas...

https://www.youtube.com/watch?v=fAMSWqJxQ3Y

I first viewed this video some time back when I initially thought about making my own pellets. It's true, my pellets are made using the same basic principles. The only differences are the overall weight, (30 grains vs 16 and 18 grains for 22 caliber) the profile of the pellets and the fact that I don't use a hammer to do my swaging with.

Even with one of my 18 grain swaged pellets I get a rainbow-type trajectory. At thirty grains, I can just imagine the trajectory being like that of throwing a rock; and the velocity about the same as throwing a rock unless these "PileDriver" pellets are being shot out of a PCP air gun.

I do recall after viewing this or one of his other videos, posting a question about velocities and the ability of a typical 22 caliber air rifle to stabilized his "PileDriver" pellets in flight. I checked back for a reply periodically but eventually just never went back to see if I'd gotten an answer. There's a tricky balance between weight, length, velocity and rifling twist that have to be met in order to get a decent shooting pellet. (If I'm not mistaken, my 22 cal air rile is a 1 in 16 twist.)

I have shot 24 grain conventional pellets out of my Break-Barrel Gas-Piston gun and the velocities were in the high 500 fps to low 600 fps range. I shot just a few. After that these heavier pellets just sat on the shelf until now. I stuffed all these same left over heavy pellets into my new swaging dies and used them as fodder for tweaking my existing pellet design.

My pellets were made more with Break-Barrel air rifles in mind. Testing is ongoing.

HollowPont

koehlerrk
01-11-2015, 02:14 PM
Sounds like you've got a good idea of what you're doing, one point from that vid that stuck out to me:

Longer pellet length means more bore friction and may result in lower overall velocity.

Maybe you can knurl your pellets, or add a couple cannelure grooves, to reduce the bore contact friction. It's an idea anyways...

Good luck and keep us posted on how you do.

HollowPoint
01-11-2015, 06:45 PM
I can't really claim the idea as my own. I'm sure there are countless other folks who've dreamed of making their own pellets rather than having to buy them.

If you consider that the minimum wage here in AZ is around nine-bucks an hour and a tin of conventional 14 grain pellets cost about that much, it's no wonder lots of air gun shooters might find making your their pellets something to seriously consider. The 18 grain conventional pellets cost even more. That's an hours wage just to buy one tin. Depending on how much you shoot, it could get costly over time.

I hope I'm not coming off sounding like I'm trying to get folks to abandon their conventional pellets only to find that my particular design don't shoot as well as conventional pellets do in their particular air guns. If your air gun shoots the tried and true conventional first generation pellets well, I see no reason to change . They're really not that expensive. My Umarex Octane shoots these older pellets extremely well. I'm just tired of having to buy more of them. And wouldn't you know it; the pellets my gun shoots the best tend to be the most expensive to buy.

I got a chance to do some more chronographing and accuracy testing this morning. I tested some 16.3 grain, 17 grain, 18.4 grain and 18.8 grain pellets. I shot them the same way I shoot when I'm in the field; that is, off of shooting sticks while standing up. Before this shooting session I made it a point to weight-sort them to pick those pellets as close in weight to one another as possible. None were more than .2 grains different.

Shooting in my back yards only gives me a distance of 20 yards from the muzzle to the backstop so take what I'm writing with a grain of salt. My gun is sighted in for the 14 grain Crossman Premier hollow pointed pellets. When shooting my 18.8 grain swaged pellets, the point of impact was about 1.5" low and about 2 inches to the left. The 18.4 grain pellets were about 3" low and 1.5" to the left.

The 17 grain swaged pellets impacted 3" low and 1.5" to the left. The 16.3 grain swaged pellets impacted about 2" low but the vertical was just about dead on.

I did get a couple of flyers. One with the 18.4 grain pellets; I damaged the skirt on that particular pellet when I was stuffing it into the chamber. I knew I had smushed the edge of the skirt on that pellet but I went ahead and shot it any way. Now I regret it. The other flyer was with the 16.3 pellet. I have no excuses on that one. Oddly enough, the flyer caused it to impact in the bulls-eye. All other impacts with the 16.3's were just below the 2" diameter target.

I'll photograph the targets tomorrow and post them after editing them. I only shot 5 rounds of each with the best clustering group of the bunch being the 17 grainers. As luck would have it, the 17 grain pellets are the least finicky to swage in terms of weight so I don't have to fiddle around with trimming the tails once their swaged. And, at 17 grains they fall right between the extreme weight differences I was shooting. It's a good weight to velocity ratio.

I suspect that my go-to pellets will be these 17 grainers once I run out of the last of my 14 grain Crossman Premier pellets. I think that all I'll have to do is adjust my sights a little and I'll have some accurate and plentiful pellets to shoot from now on.

I'll post those target picks a little later.

HollowPoint

HollowPoint
01-11-2015, 07:37 PM
I thought you might like to see what my initial Pellet Swaging Die turned out like. This is the one that I screwed up the diameter measurements on. The pellets I Swaged with it are made from the 21 and 24 grain conventional Jumbo Monster pellets I mentioned in one of my previous posts.

The pellets pictured here measured a finished .224" in diameter. The Sizing die I made later brought the body diameters down to .2145".

Just a side note: I started a Umarex Octane users group back when I first bought my Octane air rifle. I was looking for information on how to do a trigger job and other mods on my gun. When I couldn't find any of the information I was looking for, I started my own group on the Yahoo Groups site. The details of all my mods; including more pics and details on this Pellet Swaging Project can be found there.

HollowPoint

Outdoors
01-11-2015, 08:51 PM
That is very cool.
Looking forward to seeing more on this project.
Pat

HollowPoint
01-12-2015, 01:45 PM
Sounds like you've got a good idea of what you're doing, one point from that vid that stuck out to me:

Longer pellet length means more bore friction and may result in lower overall velocity.

Maybe you can knurl your pellets, or add a couple cannelure grooves, to reduce the bore contact friction. It's an idea anyways...

Good luck and keep us posted on how you do.


I was concerned about the friction of my pellets as well. This is why I went with a Bore-Rider Design and a very thin skirt at the base to form a gas seal and to impart spin.

I did do some shooting into a block of what I thought was a thoroughly water-saturated piece of high density foam. It turns out that only about the first three inches of that foam block were truly saturated so once the pellet went beyond that three inches it was basically flying through plain foam. It traveled about ten inches before it stopped.

My main reason for doing this was to find out if or how much these Hollow-Core Bore-Rider pellets were expanding once the high pressure air impulse pushed it forward. It turns out that the pellet did appear to be obtruding just enough to be engraved by the lands in the bore but, not enough to bottom out into the grooves.

I think if I tweak the reamer that I'm using to make the cavities in my Swaging die, I can further mitigate the slight drag that's imparted by skimming the lands. If I get some free time in the near future I'll give it a try.

In the mean time, here's a pic of what I'm attempting to explain.

HollowPoint

melloairman
01-12-2015, 11:05 PM
Is your barrel choked ? That could be causing more engraving than you expected . Interesting project with promising results .Marvin

HollowPoint
01-13-2015, 11:24 AM
Is your barrel choked ? That could be causing more engraving than you expected . Interesting project with promising results .Marvin


To the best of my knowledge, the barrels on the Umarex Octane air rifles are just your run of the mill air rifle barrels. There is no "Choke" that I know of.

HollowPoint

HollowPoint
01-14-2015, 05:05 PM
Since I'm able to try different pellet weights using the same Swaging Die, I've been Working-Up-Loads (so to speak) by varying the weights by .3 grain increments. I'm doing it the same way I would if I were Working-Up-Loads for my centerfire rifles.

I use the Optimal Charge Weight method on my centerfire rifles but with an air rifle the Pressurized Air Impulse stays generally constant with only a slight variation. That Pressurized Air Impulse in an air rifle is the equivalent of the Powder-Charge in a centerfire cartridge so, when working up loads for my Umarex Octane air rifle the only thing I have control over is the weight of the pellets.

With that in mind, I swaged several more pellets. This time I made a few that weighed 15.8 grains, a few that weighed 16 grains right on the button and a few that weighed 16.3 grains.

I never would have thunk it but, the groupings that I got were very similar to what I get when I work up loads for my centerfire rifles using this same method. Apparently, even air rifles exhibit barrel harmonics because by laying my targets side by side from the lightest pellets to the heaviest pellets it's very apparent from the Point-Of-Impact shifts that a pattern develops.

During this latest shooting session, it was interesting to note that the pellets weighing from 16 grains to 17 grains tended to impact into tighter clusters than the lighter and heavier pellets. Then, once I reached the 18.8 grain pellets the groups started tightening up again.

On my next shooting session I'll try some 16.5 grain pellets just to confirm my findings. If these same results are repeatable, that will mean that I have a "Optimum Charge Weight" or Optimum Pellet Weight from 16.5 to 17 grains that will still get me into the same Point Of Impact.

I really never thought that it would work out this way but upon some reflection, I supposed we all have to try different pellets till we find one that our air guns like. Since most of the pellets we try are basically of the same first-generation design, we're simply doing the same thing I've been doing by testing different pellet weights. The only difference is that my pellets have a different, and possibly more finicky profile.

HollowPoint

HollowPoint
01-15-2015, 02:32 PM
I Swaged up a few more pellets. I decided to make them from 16 to 17 grains just to try to confirm my previous results weren't a bunch of flukes. I'm happy to report that for the most part, my points of impact were generally the same.

I did have some differences and some flyers that I believe were caused by me going back and re-swaging some of the heavier pellets I'd previously made to get them down to the lighter weights. I can't really say that was what caused the flyers. It's just the only other thing I can think of; other than it being my fault and not the pellets.

Here's another bunch of target pics. You can compare them to the previous bunch of target pics I posted to get a feel for what I'm getting out of this new pellet design.

HollowPoint

HollowPoint
01-18-2015, 05:58 PM
Rather than making another reamer and starting from scratch with the last tweak I may have mentioned before, I decided to use a Work-Around. I made another simple sizing die in order to get my existing Swaged pellets down from a diameter of .2145" to .214" even.

I wanted to get the diameter down to .214" so that when it was fired, the "Lands" in the rifling just barely made contact with the "Bore-Riding" section of the pellet and just a small width of the tail actually got engraved by the rifling to form a high pressure seal.

In my mind, this would have served two purposes. One was to lessen the frictional drag on the pellet as it moved down the barrel toward the muzzle and two; the .214" diameter would still keep the pellet perfectly aligned as it spun down the bore.

Because there really are no reamers I can buy that are exactly .214" in diameter I had to use one of the reamers in my reamer index that was closest to that dimension, then slowly and meticulously open up the cavity with very fine sand paper until I reached the desired diameter.

In the end when I had it finished, I sized several pellets and they came out as I'd hoped. They fit snugly in the bore but not to the point that I had to force them into the chamber. The thin width of the skirt retained it's original diameter of .2185". The Skirt is what engages the rifling to impart the spin of the rifling.

It took about two and a half hours and after all that work followed by testing, I found that the gains that were made were so miniscule that it was hardly worth the effort because in addition to minimal gains, it also added another step to the pellet making process.

After some more testing, I did arrive at a definitive pellet weight that gives me optimum velocity, accuracy and down range energy for this home made pellet. At 16.2 grains, this new pellet design tends to give me enough of all of the above that it's the weight I'll be shooting these new pellets at from now on.

I also want to mention that this 16.2 grain weight falls almost exactly right between the two other pellet weights that gave me the best accuracy. These other two pellet weights were 16.3 and 16.15 grains. All of the pellets that I shot in this weight category were impacting at or near the same place consistently.

I've set my adjustable Pellet-Slug-Mold to drop little lead slugs weighing 16.5 grains. At this weight, when I Swage these little slugs into the finished pellets, there is minimal trimming of the tails needed and 8 out of 10 of the pellets I swage falls right at the 16.2 grains I'm shooting for. The remaining two out of the 10 fall either at 16.3 or 16.1 grains or there about. It makes it easer to sort them by weight.

And so now, I can finally call this project a success. I'll never have to buy pellets again. If I want to try testing a heavier pellet, I can do that at my leisure. The 18.8 grain pellets also showed some promise on target but, for now, this project is done.

I hope it's been of some interest to some of you guys.

I have just a little under 400 of the Crossman Premier 14 grainers left and I just found a tin of H&N 21.14 grain Baracuda pellets I'd forgotten I had so, I won't be transitioning over to my new pellet design until after I've shot up all these conventional pellets.

That's it for now.

HollowPoint

Camba
01-25-2015, 07:06 PM
I am wondering if you can use a blank mold with handles from Lee. Maybe you can even make some to sell.
Camba

HollowPoint
01-29-2015, 03:11 PM
I'm sure a "Blank-Mold" would work but, one of few reasons for using the Swaging-Method of making these pellets was so I could use up some of the scrap metal pieces I had in my junk box without having to spend money on a mold or the materials to make a mold.

Another reason was that I had heard that -generally speaking- you tend to get more concentricity and weight consistency by swaging than by casting a finished projectile; especially on something as small as a pellet.

After I'd finished the final swaging die, it took a while to figure out the best way to go about swaging these little pellets. I mean, it took me a few tries to figure out the best amount of pressure to apply, the best way to trim the extruded lead off the tails, etc. I got it down to where 8 out of 10 of my swaged pellets falls right at 16.2 grains.

Also; I mentioned in one of my previous post that I found a new tin of 21 grain pellets that I didn't know I had. Well, I discovered that I can just stuff those pellets -one at a time- into my swaging die and transform them into this new pellet design with just some minimal trimming of lead off the tails.

I still have a bunch of conventional pellets left before I adjust my sights to correspond to the point of impact these new pellets are giving me. I've been Swaging a few new pellets at a time whenever I get some free time to do so. I figure by the time I run out of the conventional 1st generation pellets, I should have a pretty good stash of these new pellets on hand.

HollowPoint

Outdoors
01-29-2015, 09:38 PM
Wow, very nicely done.
Your skills never cease to amaze!

Pat

HollowPoint
01-30-2015, 12:00 PM
Thanks for the kind word Pat. I'm pretty sure that most guys would be able to make a similar die set up with a minimal amount of specialty tools.

With a drill press and correctly sized drill bits, a rudimentary swaging die could be made using a hammer to compress the lead if a dedicated press of some sort weren't available.

HollowPoint

Outdoors
01-31-2015, 05:01 PM
I've been scouting for a decent drill press and may give this a try. Looking over the little 22 hp/swager that Paco Kelly makes, I've wondered if I could duplicate it with some drills and step reamers .... But I may prove yet that I am not like most guys:) My machine shop days in HS are nearly 35 years in the past now.

Pat

HollowPoint
02-01-2015, 02:27 PM
I'm sure you've heard the old saying, "If I Can Do It, Then Anybody Can." A project like this falls well into the realm of this old saying.

Don't underestimate your abilities regarding this simple type of project. In my case, even though I have a metal lathe and a CNC mill at my disposal, I still ended up having to make three different dies before I got it right; and just as I was finishing each of those attempts I would come up with ways of doing it a little easier or a little better.

The final results depends on your true bore dimensions. On my 22 caliber air rifle, I ended up with a finished pellet diameter of .2145". Then I lightly Chamfered the tail end in order to create a good seal against the burst of high pressure air that propels the pellet; in addition to engaging the rifling to impart spin for stabilization in flight.

I mentioned this before in one of my post. They don't make a .2145" drill bit or reamer that I know of so, a guy could use a 7/32" drill bit to bore the hole in your swaging die to form the pellet, then make a sizing die using a 13/64" drill bit.

The 7/32" drill bit diameter is a nominal .21875". It doesn't matter to much if it's exact or not because you'll be sizing it down to the correct diameter. The 7/32" drill bit that you make the sizing die with is a nominal .203125". Here again, it doesn't matter if it's not exactly the stated diameter because the sizing die hole will need to be manually opened up to the right dimension/diameter.

To open the sizing die up to the diameter that best fits your bore, you just polish it out with fine emery cloth until you reach the desired diameter.

Attempting to describe the procedure with the written word makes it all sound a whole lot more complicated than it really is. Basically all you're doing is drilling two different sized holes. One for your swaging die and one for your sizing die. The sizing die whole gets reamed out to proper size. (possibly three holes; the third being a very small hole for pushing the pellet out of the swaging die after it's formed)

The point of your drill bit will form the point of your finished pellets. That's it in a nutshell. From there you can make it as simple or as complicated as you feel necessary to get a good shooting pellet.

HollowPoint