45 caliber Air Rifle

[Butcher45]

("From what I have gathered thus far, any airgun calibers appear to have a power-ceiling, with the larger calibers having more fpe potential. Meaning the greater the area for the air to operate in AND ON, the greater the power potential.

The rebated boat tail's very minute increase in barrel volume (the "area in" part) is not what I'm getting at here, but the "area on". That boat tail base provides more area for the force of the air to be applied. A substantial increase in area over a plain base. I'm thinking this additional area just might provide some of the benefit a larger caliber also brings.")

Hey Butcher:

Do know of any links you can refer me to so I can read up on exactly what you're trying to explain in the quoted sentences above?

I believe you know what you're talking about but, I'm having trouble understanding it. I thought perhaps if I read the same things you've read concerning air guns and power ceilings and surface areas and such, I could better understand what you're getting at.

The bullet study that I googled up the other day that lead me to design the bullet in the drawing I provided seemed to indicate something slightly different. Of course this study I'm referring to applied to conventional firearms; not air guns of any kind. I just assumed that this same study might have some relevance to air guns as well.

Following is the link to that study. http://www.swage.com/ftp/rbt.pdf

It's true I'm looking to make an accurate air gun bullet but not to the exclusion of terminal ballistics. Thats where a shallow hollow point comes in. With air gun slugs cast as soft as they are, even a shallowest hollow point should induce expansion even at the slow speeds that these big bore air guns function under.

Even a slight expansion should compensate for the generally low terminal ballistics of an otherwise pointy nose bullet, while hopefully still retaining its aerodynamics and accuracy .

HollowPoint

I think you are going to need a cavity quite a bit wider, and a bit deeper than the one in your initial blueprint to achieve pedaling/expansion. That cavity looks like it would just smear/deform. Cavities that are fat, and of medium depth seem to be working the best overall for the people shooting HP's (with both accuracy, and expansion).

The best place to do research on technical airgun stuff is here. All you have to do is ask, and some of the most experienced airgunsmiths in the world will be there to answer.

http://www.network54.com/Forum/79537/

[HollowPoint]

I spent most of the day today working on what I hope will be the first of several Air-Gun dedicated bullet molds.

Encouraged by several recent posts by guys on this forum showing their first ever bullet molds I finally quit procrastinating and went at it. So far it's going quite well.

The only thing I struggled with were the alignment pins but, I finally got it worked out by using some of the examples shown by a couple other first time bullet mold makers on this sight.

This first attempt will be as simple a design as I could do. It's a close copy of the EPP/UG bullet. The only difference is that the forward part of the bullet will be at the diameter of the bore, (.453) with the middle driving band being .456" and the tail end driving band set at .457"; and it will be hollow pointed.

I had a couple of old Lee Two-Cavity Sprue Plates laying around. They were left overs from two molds I ruined a while back. I also had the mold-handles from those two ruined mold so I'm putting them to good use. I'm using a piece of aluminum that used to be a suspension part off of a Cadillac CTS. I got it from the Body-Shop junk pile where I used to work.

Before I went back to self-employment, that junk pile used to be a gold mine for miscellaneous metal stock.

Tomorrow I hope to finish up most of the details before I actually make my bullet cavities. I'm probably going at it bass-akwards but, that's OK. I just need to get this experience under my belt, then I can have a little more confidence when I attempt to make up the mold for the bullet design I posted earlier.

It feels like it's just one more step to being fully self-sufficient with respect to hunting and shooting.

With this air rifle, I haven't had to buy powder, primers or shell cases. The peripheral accessories took me a while to acquire but, now I can just cast my bullets and go shooting.

I can't see myself ever selling all my firearms but, I'm starting to feel like I may be letting a couple more of them go just so I can purchase another Big Bore Air Rifle to Tinker around with. I'm fairly certain that I've acquired enough knowledge about these Sam Yangs to be able to convert one over to .30 caliber.

Well, I'm starting to ramble on now so I'll shut up for now.

I'll post pics of this Big Bore Air Rifle bullet mold when I get it finished up. The reason I went at this mold in the order I have been is because I'm waiting for the boring tool I ordered to arrive. I can't make the bullet cavities till it gets here.

HollowPoint

[HollowPoint]

I've gone as far as I can on my present attempt to make my first Big Bore PCP specific bullet. My plan was to make them match the dimensions of my Sam Yang's bore.

While I'm waiting for the Boring tool I ordered I thought I'd post the first bullet design I drew up. I posted the second design ahead of it because I personally thought it was a more aerodynamically correct Air-Bun bullet design.

The bullet design I'm posting here is a lot more complex. (at least for me to build) It may be way out of the realm of possibility for a novice bullet and mold designer/maker. (like myself for example) I guess I'll find out when the time comes.

Right now I just want to finish and cast with the mold I'm working on now before I get ahead of myself and start rambling on about these other two designs.

Check it out.

HollowPoint.

[JIMinPHX]

I'll say again that I'm no airgun expert, but one thing crosses my mind. Is there any real value to having such deep grooves? Once your grooves are about .01" below the minor diameter of the bore, does going smaller really help in some way? There may be a good reason for it, but it's just not obvious to me, so I'm asking.

[HollowPoint]

From an aerodynamic stand point I don't believe there is any real value other than maybe to help reduce the weight of the projectile while maintaining a certain length.

I prefer the initial design I posted. The main body of the bullet is sized so that it rides the bore and the thin driving bands are just big enough to initiate spin and seal the air behind it.

The design in thread 163 was meant to emulate some of the existing Big Bore Air gun bullets. Most -if not all- of the more accurate ones tend to have pronounced driving bands that stand much taller than the core of the bullet.

Why? I have no idea. In the little bit of informal research into optimum bullet shapes for slow moving bullets like these Air Gun slugs that I've done, I haven't come across anything that would even remotely suggest that these "pronounced driving bands" are ballistically beneficial. I suspect it's just a case where everyone's trying to copy everyone else. I'm afraid I'm guilty of that.

Why? Old habits die hard. The only thing I tried to do differently is give it a pointy nose and a hollow point to enhance the aerodynamics and try to distinguish my bullet.

I think at some point someone must have stumbled onto that "pronounced driving band" design, it worked well in their gun and maybe several others so no one bothered to do much more R&D other than cosmetic changes in order to claim a new design.

I've seen the same phenomenon with bullet casting and designing for traditional firearms.

When was the last time you seen or signed onto a group-buy for a bullet mold of a new design? One that's almost radically different but, shown to work?

I haven't been a member here that long but, I've never seen a group buy that featured anything but bullet molds that cast bullets similar-to or copies-of existing bullet molds. It's almost like no ones thinking outside the proverbial box for fear of upsetting the balance of bullet-casting-nature.

My previous design is nothing new either but, with the rebated boat tail protruding from the semi-concave base, I think it may actually work as an Air-Gun-Specific projectile.

That's the next bullet mold I'll be working on. I have the blocks nearly ready and additional metal stock on the way.

I'm deliberately trying something NEW. If it crashes and burns; so what. I'll never know unless I try. I think alot of guys on this forum have had some stellar ideas for new bullet designs but, for one reason or another, they've never brought it forth.

I'm not saying my ideas are anything stellar by any stretch of the imagination. As I stated above, my bullet designs are nothing new. I'm just trying to make the point that there's gotta be something more than the "Status-Quo" bullets we all love to shoot.

I know we all tend to gravitate toward the "Tried-and-True", "Status-Quo" cast bullets that work for us but, isn't anyone else here deliberately trying new bullet designs; regardless of how radical they may appear or the oppositions they may encounter because of them?

Since acquiring this new .45 caliber Air Rifle, I thought I'd do just that. I may ruffle the feathers of the hardline traditionalists. I may waste alot of time with little in the way of positive results but, on the other hand.......

HollowPoint

[HollowPoint]

I got a chance to go out this morning and do some informal "Stump-Shooting" with my newly acquired Sam Yang .45 Big Bore.

I have to say, I was impressed. Not with myself as the shooter but, with this Air Rifle's performance.

I was shooting some of my 200 grain Lyman Devastator slugs. Again; I was impressed. They seemed to be hitting right where I was aiming.

Not bench-rest accuracy mind you but, plenty accurate for rabbits and coyotes.

I fired only four rounds at a time then I'd recharge my air reservoir. Each of these four rounds hit close enough to the same point of aim that I couldn't really tell if there was any loss of velocity.

I had my range finder with me so I was deliberately shooting out to a hundred yards with the same results. I'll make it a point to take my chronograph with me next time. Hopefully by then I'll have my first bullet mold finished so I can test some slightly lighter bullets.

I did have some of the bullets that JIMinPHX gave me. They varied in size and weight but that didn't seem to make any difference accuracy-wise. They seemed to hit where I was aiming as well. I think a more formal shooting session is in order now.

With the recent storms we've had here I was hoping to come across another toppled over sahuaro cactus. Sure enough; I found one and took a shot from measured-50 yards. It was about 11 or 12 inches in diameter and I had planned on doing some minor surgery on that cactus to retrieve the bullet but, it had passed clean through.

That really surprised me; given that they were cast from straight stick-on wheel weights. I would have figured that these soft hollow pointed slugs would have flattened out like a pancake and not penetrated very deep.

I really hope that our Game And Fish department changes the hunting regulations for pneumatic weapons to include coyotes. As you may have heard, right now the only thing that can legally be hunted with pneumatic weapons here in Arizona are rabbits.

Now I'm really anxious to get my bullet mold finished. I think this Air Rifle is going to work out real well for me. If any of you have considered getting one, I can't say enough good things about them.

HollowPoint

[JonnyReb]

Hi Hollowpoint, i joined C.B. as i was given the link to this forum while searching for the best boolit for my Sam Yang. This link came up, also a member at an airgun site linked me over. Nice to meet ya'll.

I look forward to seeing the results of your new molds in action, how is it coming along?

My .45 is an early manufacture Sam Yang, a bit low in power compared to the newer model. Like you, i am VERY impressed with the gun, mine is very nicely put together, a joy to shoot. With .454 and .457 roundballs i'm seeing strings starting at 700fps or so and the next 4 shots are pretty consistent with that number. Accuracy is astounding , i had no idea a gun could throw a roundball so well.
I've also just experimented with a muzzleloading .45 plastic sabot holding an 155gr. xp pistol jacketed round. This shot well also and netted me about 648fps... 145ftlbs.. nothing to scoff at but not exactly a firebreather either. It does however, open up the possibility of using other .401 cast or jacketed boolits for lower weight projectiles and higher velocity.

On order are 150gr. epp's, i can't wait to get them and give em a try. I'm going to base the purchase of my first mold on the results of the epp. Look forward to hearing of any progress you've made in finding a "perfect" round for this gun.. J

[HollowPoint]

Greetings JonnyReb:

And welcome to Cast Boolits. It's an honor to have you post your first reply on one of my threads/posts.

I think that the "Best Bullet" for our Sam Yangs is the one you can get to give you the best accuracy and power without having to spend a small fortune -repeatedly- in order to get more of them.

One of the main reasons I'm attempting to make my own bullet molds is because I'm trying to attain a certain amount of self-sufficiency when it comes to bullet casting and reloading. That's just a round-about way of saying that I'm cheap by nature and a chronic do-it-yourselfer.

It's a slow work week this week so I'm spending my time trying to finish up my first mold so I can start on the second.

I'm afraid I'm getting to impatient. I have the habit of rushing things and that generally means my original plans turn out a little different than I originally planned.

I got the first mold nearly complete but, rather than having the three driving bands I'd intended to copy from the UPP/bullet, I decided to make it with the main body of the slug .452 in diameter and just one single driving band at the rear of the bullet that measures .457. It also has a shallow hollow point.

If it were a rifle-type bullet it would be called a "Bore-Rider" but, since it's a pistol bullet I don't know if that designation still applies. Oh well; If it works, it works; if it doesn't, it doesn't.

I'm making it out of an old Lee two cavity .30 caliber mold that I ruined a while back. To make myself appear to be more politically correct I guess I should call it recycling.

I'll just keep plucking away till I get it done. It's the next bullet mold that I plan on trying to be a little more meticulous with; although I'm pretty sure that mold will also end up putting out cast bullets that look slightly different than what I had drawn as well.

HollowPoint

[Butcher45]

Good to see you found your way over JonnyReb I have a feeling there will be a lot of airgun boolit R@D going on in the near future. Especially for the common/popular Korean barrel profiles.

[JonnyReb]

Thanks for the warm welcome guys, glad to be here. Nothing i like more than a site full of folks who love my various shooting related hobbys as much as i do. This place seems full of people who have "been there, done that" and i hope to pick up as much knowledge as i can.

Butch, you i think, know as much about preferred bullet design in the SY as anyone alive judging from a google search of best bullets for the sam yang. Hollowpoint, you have designed what looks to me like the best large bore pellet design on the face of the earth.. just my opinion, but i sure look forward to seeing your results. I was reading in a copy of the book "Lee reloading"(2000 ed.) last night and Richard Lee said he would make anyones mold into production reality for a hundred dollar set up fee + the regular cost of the tool. I don't know if that still stands but... i thought i'd mention it. Anyways, I'M the one who feels honored to be here, i feel like i will learn lots about this gun over the next few months and i'm sure looking forward to sharing info with you guys. BTW Butcher, thanks so much for the info on the tuners, it is very appreciated.

I can't wait also to begin casting my own slugs for both air and powderburners, i'll be spending a lot of time here for sure. J

[PatMarlin]

Welcome to cast boolit heaven JonnyReb! ..

We have a good number of fine craftsman mold makers here at CB. I'm sure we could do a group buy for your air gun mold at a lower cost and much better quality than LEE.

[Pepe Ray]

Good morning gentlemen;
Allthough there have been a few interruptions, I've been following this thread with GREAT interest.
Not being a NET SURFER, could I ask for someone to post a link to a retailer of these remarkable BBAR's (Big Bore Air Rifles)?
Also, are the portable pumps usually available from the same dealer?

I tried to get a line on a Quackenbush but that's out of the question for one who doesn't buy 'green bananas'.

Thanks for any and all assistance,
Pepe Ray

[scrapcan]

Pepe,

Lik eyou I am also watching closely and trying to get into this interesting aspect of the shooting sports. The above guys no way more than I could hope to learn so listen to what they say.

There are a few dealers. Not sure who is the best price right now though. PyramidAir, airgundepot, Cobra airguns.com, etc..

For the portable manual operated pump you will want to go with the Hill pump. There are other pump makers, but he hill is the top of the line and reliable.

i am trying to trade myslef out of a few things so I can upgrade to on of these abig bore airguns.

[JonnyReb]

Hi guys, thanks for joining in!! In my opinion, pyramid air, using their 10% off code (summer2010), has the best prices on bigbores. The .50,.45 and 9mm is carried by them and they have quick shipping and a good service dept if ever needed. Also, you can google "Airgun classifieds" or "yellow forum classifieds", as i did, to pick up a bigbore for about $400.00. A used manual pump on the classifieds will run anywhere from $125.00 and up. A scuba tank can be had new for $140ish and the adapter and fill station run another $70.00 or so. I went used for the pump and gun and ended up at around $600.00. Couldn't be happier. For a bit more power, google "southern airgun conversions" to find a site that sells semi custom bigbore .45 and .308 for a few hundred bucks more. I think bigbore airgunning is here to stay, i can't wait to see new products emerge over the next couple years.

This whole bullet topic is new too. Anyone on the forefront, designing and building bigbore airgun ammo will find themselves much in demand.. as right now everyone is using the available roundballs, foster type slugs and muzzleloading designs... none of which are really made for the special demands of an airgun. The above design is the only one i've ever run across.. and it looks well thought out.. quite viable it seems.. group buy you say?? .... i'm gonna really like this place.. J


edit: I hope this is allowed, i wanted to post a link to an AG site, a thread with some good info on it. Some of it relates to hunting and there are some photos that some may not be comfortable with seeing. mods please remove this(but not me ) if it's a problem.
http://www.gatewaytoairguns.org/GTA/...p?topic=1852.0

[melloairman]

These smiths have a waiting list normally but here you go .Marvin
I have a J.H.32 and it is a good rifle
http://www.southernairgunconversion....irguns_002.htm
I have a Gargoyle by Dan which I have yet to shoot but the workman ship is there . He tuned it to put out 680 fpe.
http://www.xp-airguns.com/
Here is Leroys site the inovator of the Gargoyle.
http://www.bgmfairguns.com/index.html
And DQB site .
http://www.quackenbushairguns.com/

[HollowPoint]

Good Morning Gentlemen:

It's good to see a few more Air Gun enthusiasts on this thread. And it's always good to have all the other Cast Boolits craftsmen and fans like Pat and Jim chiming in when they can.

I spent most of yesterday trying to make a "Cherry" for my bullet mold. The first one turned out slightly smaller in diameter than I had hoped so I did a second one that seemed to fall right into the dimensions I was wanting.

Turning them on the lathe is fairly quick and easy but, most of that time was spent milling the flutes on this reamer. With my little cheapy Harbor Freight bench top mill it can only handle small bites of metal with each pass of the end mill. I'm not kidding, it took me about an hour or so for each of the four flutes.

These little machines just don't have the torque to mill any faster and right now I don't have the money to buy a better machine so, it's going to have to do.

I wanted to finish as much as I could cause tomorrow I have a job coming in and I don't know when I can finish up the work on this bullet mold.

I intended to answer Pepe's question about the retailers that sold these Sam Yangs but, it seems that one of the other Air Gunners has taken care of that.

I got my Sam Yang and my hand pump from Pyramyd Air. They were both on sale at the time I puchased them. I think I got a good deal compared to some of the other retailers. It's like any other purchase though; you have to shop around. At any give time you may be able to find a better deal at one of the other sellers.

HollowPoint

[HollowPoint]

The job I had scheduled for today didn't show up until mid-afternoon. It was supposed to arrive at 9:00 AM this morning.

While I waited around I decided to work on finishing up my number 2 Air-Gun-Dedicated bullet mold.

It started out good but, after misaligning my cavity holes, ruining my sprue-plate and having my newly ordered metal stock not show up, things kind of went hay-wire for a while.

I originally intended to make this mold a four cavity but, because of my misaligned cavity holes I had to cut it down to a three cavity mold. When I cut it down to accommodate my three cavities I cut to close to my alignment pins, which left them partially exposed but still functional.

If it's true that we learn from our mistakes then I should be a freak-en genius.

I also intended to make these bullets aerodynamic and hollow pointed. I had ordered some additional aluminum flat bar which I was going to use as the form for the rebated-boat-tail ends of my bullets; however, that flat bar didn't show up so I decided to go with the "Nose-Pour" style of mold instead and put the rebated-boat-tail forming fixture on a cramer-style fitting.

Since my bullet mold was now a "Nose-Pour," that meant that I'd have a semi-round flat nose so I varied the sizes of the Nose-Flats, bullet sizes and the lengths of my boat-tails.

If none of these descriptions make any sense I've included a couple of pictures so you know what I'm babbling about.

When my previously ordered flat bar finally shows up I'll be able to use it to make what I'm pretty sure will be a more refined Air-Gun-Dedicated Bullet Mold. And this time I know it will come out like I originally intended.

HollowPoint

[Butcher45]

Getting three designs out of that mold (instead of three cavities of just one design) puts you way ahead of the game for your testing. However this turns out, it sure is interesting to be able to watch from the get-go.

[Marlin Junky]

Can the 909S be filled from a hand pump?

MJ

[Larry Gibson]

I'm coming into this a little late perhaps but I always thought the Rapine 460210 would be excellent in such an air rifle. It is a HB with a very deep tapered HB. I use it in my 45-70s at 600 - 1000 fps with small doses of Bullseye. It is a deadly small game getter. The photo's show it (bullet on the left).

Larry Gibson