Most slugs are a waste of money because you did not slug your barrel

Roach, you only partially covered the choked barrel slugging. You explained how to do it, but you did not explain which diameter to use for the slug, the choked or unchoked diameter. Since you say you don’t bother with choked barrels for slugs do you have experience or an answer to the question? If you don’t know please just say so. Thanks. 

Thanks. It’s been a lot of work to find a slug to shoot in a choked barrel. Got lucky and tried the NSA 20.2 grain HP DB in my EDGun R3 Long at 975 FPS. Inside an inch on 5 out of 6 groups (5 shots each) at 110 yards three weeks ago. The gun has a fairly light choke. I haven’t tried the FX hybrid (ratsniper) slugs yet but plan to soon. Here’s two of the five shot groups at 110 yards. One 5/8 inch the other 7/8 inch. 

There is definitely more to slug shooting than just the barrel. I have 2 identical TJ .25cal barrels mounted on 2 different guns. The one does great at 850fps with a VK 31.5, the other gun does not. I put slug barrels on guns I want to shoot slugs out of but you cant rule out choked barrels seeing how some .22lr barrels are slightly choked. Keyword slightly.

nice shooting CC

I read entire post and I first off agree that , Dave Corbin is a master at making Swag equipment and has designed some of the worlds most accurate slugs in world ,

He will tell anyone straight out about getting a proper of measurement of you barrel , He has told me decades ago , about adding 1/2 a thousandth to your smallest measurement of either 1 running 6 slugs or pellets threw and measuring all and getting an average and add .0005 .

or 2, making a small cast of your muzzle with like a low heat materal , and measure this as it will be tigher at muzzle ,

But there is soo much more to a slug gun then the barrel and how much power you have which all account for precision accuracy and repeatability ,

Even things like seating depth matters in powder burners we use tools to see how long to reload our ammo so we have proper seating depth , so same goes with slugs , many pellet guns need some type of breech mods to seat at proper depth , and you may have to ream your breech to shoot long slugs , I prefer reaming breech then using a slug with a grease ring so it chambers , also pellets are hollow so many pellet guns may need your loading pin adjusted to your ammo

Some slugs like MP slugs use rings which are slightly different diameters and they work like a skirt , so you get proper seal and loading is perfect .

But I have had 6 blanks from and many do vary yes , and Years ago Tj did vary . so Like anything else if you start with a handpicked one you will have alot better accuracy . with pcp pellet guns , it is a real nite mare for companies to make proper ammo as they make it for all guns and all vary . with airguns their is no standard

like real guns . .308 is std size in any 30 cal , and with 50 cal .510 is std

with pcp guns we have .22 cal , .214 old evanix , .216 .217 most , up to say heubon .223

with 30 cal we have .299 , ,300 ,308 and some true .308

so alot of tolerances which is why I have so many molds , but when I get one which is best ,either a mold a swag die or a premade slug , I stock up as it works well.

LOU

Nation, 

That is why I decided to invest and go with Corbin for all of my swaging needs.

Several years ago, I had him make 4.52mm and 4.53 mm semi wadcutter dies. He made them to perfection, but these things would not fly good for the life of them in anything. 

Fast forward a couple of years, and I decided to go a slightly different route, at Dave Corbins suggestion. Instead of me telling him what I wanted, I would have him tell me what I NEEDED. I shot and recovered pellets from my RAW TM1000, and my Steyr LG 110 FT. I also sent him raw unshot pellets, as well as pellets pushed into the barrel before hitting the choke, and pushed back out. I then sent them to Dave, he inspected them through his high power microscope, and he told me what size I needed. The different types of nose shapes, base shapes (with more coming for both), along with various weights, now give me some very promising designs that are giving me impressive results. If anyone would like to see my progress, check out my U Tube Channel, Field Target Tech, and my website fieldtargettech.com. 

Tom Holland 

Field Target Tech 

I was making u-tube video’s 7 years ago hitting 12 oz cola cans at 500-550 and 615 yards with a Haley 257.

Click to expand...

Wow, you were way ahead of your times, Roachcreek!

I like pioneers!



Thanks for the barrels & slugs explanation, over at GTA I misunderstood your post. Now it's clear for me.

Matthias

Some of you guys have a ton of patience! And love to play with all this swaging, casting, etc. I don't really want to get into all that stuff!

I just want a high quality Bartlein barrel with the correct twist, rifling profile, etc, made for one high-ish BC slug, in a chamber set up perfectly for that slug, and all fitted into a heavy duty and powerful PCP made to higher quality firearms standards. 

You know, a complete system all ready to go, so there is no F-ing around with it at all, and that easily does sub moa, preferably half that. For the life of me I can't believe that such an air rifle system hasn't been made yet. 

I've shot one $3000 PCP that was very well made and pretty heavy duty but wasn't shooting well at all. Won't mention brand because I like the guy who made it, don't want to damage his rep, and hope he figures it all out eventually.

Everyone wants their air rifles to perform like the FX rifles perform with slugs. You ever wonder why FX rifles shoot slugs so accurately? It's because the slugs are slightly larger (by .0005 to .001) than the bore diameter. Remember, FX barrels don't have rifling. The barrel blanks are pulled through a hydraulic powered extruder that twists the entire barrel to create twist. All other rifled barrels are cut with a mandrel. The shape of the mandrel determines groove diameter and twist. Since the FX barrels don't have rifling, the slugs MUST be large enough to engage and concentrically seal inside of the barrel. Otherwise they would just slide right out the end of the barrel when you cock the gun and started walking around. The slugs are large enough to seal, but small enough to minimize friction once the valve releases to generate inertia. But they seal PERFECTLY through the entire length of the barrel. 

If you go to the LW website, you can readily find the dimensions for their Air Rifle barrel blanks. The .22 blank is .214/.221, and the .25 blank is .249/.254. So say you're shooting a .250 slug, you have a concentric gap of .002" between the slug and every groove. If you're using a .25 rifle set to use 3000 psi to propel your slug down range, then you're wasting air and you're destabilizing your slug right off the bat. First of all, the pressurized air is moving WAY FASTER than the slug is moving. At those pressures, the air will find any and every hole to escape from. The gaps between the slug and the grooves is the proverbial "path of least resistance". So the air that escapes around the slug reaches the muzzle before the slug itself does. So not only are you losing power from the wasted air, but the air destabilizes the slug causing wobble, or in some cases clipping on the end cap of the suppressor. The destabilization may be minimal, but a tiny bit of wobble at the muzzle equates to inches at 150-200 yards. But if the slug fits the barrel properly, and not only engages the lands, but seals the grooves, then there is zero wasted air, and zero destabilization. 

If you took a high speed camera (say 1000 frames per second) and took video footage of a LW barrel with a .221 groove diameter shooting a .218 slug, the first thing that you would see leave the barrel would be turbulent gas/air, followed by the slug. You would have to remove the suppressor to observe this, but that's what you would see. But if you shot a slug that was properly sized to .2215 or .222, you would see the slug leave first, followed by the pressurized air. You would also need less air to achieve the same velocity. 

I'm amazed more of the slug manufacturers don't offer slugs in proper sizes to fit LW barrels. The only one I know of is Stephen from AVS Slugs. He actually sells .25 slugs with a diameter of .254". They seal BEAUTIFULLY in LW barrels. I think he's getting ready to offer .22 slugs in .222" as well. What I started doing is powder coating my slugs. I've done a lot of R&D to perfect the process. I can add multiple thin coats of powder to achieve increased diameters of .002 to .003". The beauty of powder coating is it adds lubricity to the slugs. Also, after it's cured it becomes a solid, durable, cohesive piece that evenly encapsulates the slug. It's a bit malleable, so it wonderfully seals the grooves as well as engaging the lands. I spent about $100 for the set up. It was worth every penny. 

If you push a slug 1/2 way through your barrel, and shine a light from the other muzzle side, and you see a little concentric star pattern of light around the slug, your slugs are too small. All of the manufacturers produce .22 slugs in .217 or .218. They're too small for the LW barrels. Ironically, they're perfect for FX barrels. And the mass produced .25 slugs are produced with a .249 or .250 diameter size. They're also too small for the .254 grooves of the LW barrel. 

Just my $.02 

TrinityMaker,

in your post, are you saying the slugs are too small for the LW barrels, or too small for the choke of the LW barrels?

I thought in a choked barrel we'd have to size the slug to the choke....?



Anyhow, interesting reading, I'm still tyring to wrap my mind around all this...!

There's an old saying, pellets love a choke, bullets hate a choke. I hear mixed reviews on choked barrels. My input would be inconclusive and potentially inaccurate. But a barrel choke creates a .001 to .002 bottleneck at the end of the barrel. It will definitely slow the momentum of the slug when it reaches the choke. The choke is concentric, so I don't think it will impact accuracy much. But if you want to slug a choked barrel, push your slug into the breech and take a cleaning rod and push it 1/2 way into the barrel. Then shine a light from the muzzle end. Do you see light (answer, "Yes.... I see light.")? Then the slug is too small. Then push the slug until you feel it engage the choke. Push it in another 1/2 inch past that and repeat the light test. Remember, if the barrel is 24" long, and the choke is only at the last 2" of the barrel, you have 22" of barrel where the slug doesn't seal against the grooves of the barrel. Even if it seals the last 2", you've already propelled high pressure air past the slug over the first 22" of the barrel. And the air is moving faster than the slug is moving. If you go to LW's web page, you will see that even the choked barrels have a groove diameter of .221. If the choke is .002 (and that would be an aggressive choke. Most are .001 to .0015) then the choked portion of your barrel is .219". Well, all of the available .22 ammo from the manufacturers is .217 or .218, so you'll still have gapping- even at the choke.

Slugs are much harder to push through a barrel because of a surface area that is substantially larger than a pellet. Diablo pellets have 2 points of contact in the barrel. The head and the skirt. Since the skirt is cupped, it balloons out when the vale releases air and it concentrically seals against the grooves. But if you try to slug a barrel with a pellet, it won't be accurate because you're missing the air pressure component that balloons out the skirt. Slugs don't do that. They stay concentric throughout the entire process of being loaded and fired. My rifle has interchangeable barrels in .22 and .25. They were made by my buddy Alex in the Russian Federation. They are un-choked, carbon fiber wrapped polygon barrels. The .22 is .215/.220 land/groove with a 1:16 twist. The .25 is .248/.252 land/groove with a 1:15 twist. So Stephens .254 slugs are MAGIC in the .25 barrel. I'm still playing with the .22 barrel. I have powder coated some NSA ammo in .218 to get them to .2205/.221 in diameter. They seal perfectly. 

But in my opinion, if you're going to shoot slugs, I would gravitate to an un-choked barrel. This is just my preference. If you're shooting a .25 air rifle with a LW barrel, get some slugs in .254 and see how they perform. Stephen has them available in sample packs in about a dozen different sizes/weights. I'm not promoting one manufacturer above another. I'm recommending a slug size that's only currently available from one of them. I have pushed his slugs through my .25 LW barrels, and they fit and seal beautifully. Lots of guys use the Berger twist rate calculator to verify the SG (stability) for a projectile, velocity, and twist rate. If the calculator says the projectile should be stable based off of the numbers you're plugging in, and you notice instability and trouble grouping, then more than likely it's not the projectile, the twist, or the velocity. If your muzzle velocity is in the subsonic, or very low end of the transonic range, then you don't have to worry about shock waves destabilizing the slug. It's being destabilized by something else.

Shooting slugs from air rifles is still in it's infancy. There are pioneers out there that are spending the money and time to do the research to find the best combos. The Big Bores are where the attention was focused at first. But now the small calibers are jumping into the game. The small caliber barrels were designed for air rifles shooting pellets with slower twist rates. The physics of pellets are totally different than slugs. So getting a barrel designed to shoot pellets to shoot slugs accurately takes a lot of research and money. FX designed barrels specifically for slugs. No other small bore manufacturers have done that yet. They're missing out on a HUGE consumer market by not doing it. 

Thanks TrinityMaker. Your post is exactly what a slug shooter needs to understand and you explained it perfectly. I myself was never completely sold on lubing slugs but I do. With the absolutely tight seal for the length of the barrel with that much bearing surface, it makes sense now.

TM, thanks, that very good info!!!!!!!!!

+1 to ya TM!

Listen guys..... FX rifles are GREAT. The concept for their smooth twist barrel design is revolutionary and ingenious. But other than the barrel, they're using the same physics to send that slug downrange that you are. Regulated air, valve, hammer, spring, etc.... But once you understand WHY they are so accurate, the light bulb in your head goes off, and you think to yourself, "Well hell..... If a properly sealed barrel works so well for FX, then it should work for my rifled LW barrel as well." And you would be correct in this statement. According to the Berger TW calculator, the TJ's 36.2gr .250 slug should have max stability using the slower 1:17.7 twist of the LW barrel, even when shot at 900 fps. But the calculator doesn't take into effect the issue of the slug not fully sealing inside of the barrel grooves, and the destabilizing that takes place from the escaping air, and/or the slug slightly canting inside of the barrel due to the gapping. That's why a properly sealed barrel is so important. It forces the slug to stay perfectly concentric.

Now I will admit, not all barrels are made equal. L-W barrels are mass produced. Their attention to detail lacks compared to say a CZ or Russian Made, or TJ's barrel. But it's nothing that can't be fixed with a fire lap, or bore lap to smooth the inside of that thing to a mirror finish, and level out any high spots. A clean barrel will have less lead fouling. Also, twist is indeed important. The .22 LW barrel with a twist of 1:17.7 is significantly less stable than a 1:16 twist shooting the same projectile at the same velocity. 

I'm convinced FX is fully aware of why their smooth twist barrels out perform rifled barrels. But from their perspective, can you blame them for not disclosing this info? They manufacture very high end, and very expensive rifles. They dominate bench rest competitions. They're using the same projectiles as the rifled barrels. They're using the same methods to propel it down range. The ONLY difference is the barrel. And when you understand the physics of the barrel, and why the slugs MUST be slightly larger than the inner barrel diameter, then the epiphany moment happens.... 

I suggest you guys do some R&D. Maybe I'll post a thread about powder coating small caliber slugs. Then you guys can coat your own, get them to seal inside your barrels, and watch what happens. If we can PROVE what we're saying is true, then the slug manufacturers might start producing .22 slugs in .221 or .222, and .25 slugs in .253 or .254. 

Forgot to mention.... Another cool thing about powder coating slugs is there are some CRAZY colors of powder out there. Chartreuse, fluorescent, etc.... Colors that are HIGHLY VISIBLE on the color spectrum. Colors that you can actually track the trajectory of the slug with your naked eye as you watch it through your scope. You can even buy glow powders (strontium illuminate) and mix it in with your powder coating powder. It only takes a tiny bit. But if you get a cheap UV light, you can charge the slug before you fire it at night or in low light conditions. You essentially make a "tracer" round. But that's a whole other subject for a whole other thread. Like I said earlier, a clean barrel with have way less lead fouling. A clean barrel using powder coated slugs will have ZERO lead fouling. That's why even though Stephens AVS slugs already concentrically fit my .25 barrel, I powder coat them with a very thin layer anyways. 

Please do a topic on powder coating. I am currently shooting .254’s out of my TJ but I have a bunch of .250’s that need to put on some girth so I can use them.