20ga Conical Load. 20 ga Truballs?

[vh2q]

Anyone done anything with a 20 ga fully rifled, other than Sabots? How about Truball in a smoothbore 20ga? I have a 20ga paradox (vintage) that shoots 500 gr conicals (NEI mold) quite well but I have to keep them at around 1000fps or they strip the rifled choke, even when hardened up a little. Trajectory is terrible. I did shoot an Eland with the gun in Botswana in 2002 and it was quite something to see 2000lbs of meat bite the dust within 40 yards of being hit.

[Greg5278]

James Gates at Dixie slugs has a 500gr short conical. I believe he can load them up to 1450 FPS or so. Give him a shout at Dixie Slugs.
Greg

[turbo1889]

I've done a lot of work with this concept and so has Blammer.

Here are some thread links:

http://castboolits.gunloads.com/showthread.php?t=58720
http://castboolits.gunloads.com/showthread.php?t=59699
http://castboolits.gunloads.com/showthread.php?t=52050

Here is a link to a post of mine I put in on a thread that was mainly about 12ga. wad-slugs but the topic drifted over to 20ga. slugs for half a page or so:

http://castboolits.gunloads.com/showpost.php?p=728935&postcount=31

And then I have some posts on Ed Hubel's 12GAFH (12ga. From Hell) thread (pages 16-18) on my load work up and two successful hunts with 20ga. solid slugs using R-17 powder:

http://castboolits.gunloads.com/showpost.php?p=714500&postcount=326
http://castboolits.gunloads.com/showpost.php?p=732112&postcount=341
http://castboolits.gunloads.com/showpost.php?p=737871&postcount=345


Long story short, IMHO a full bore solid hard-cast slug out of a scoped 20ga. bull barrel gun using a large quantity of slow burning powder is the ultimate slug hunting set-up.

I am by no means the original on this - James @ Dixie Slugs is. What I have done so far with the 20ga. and solid slugs is based on his work and on Ed Hubel’s. Basically saying I’m standing on the shoulders of giants or something like that - You get the idea.

[Multigunner]

Anyone done anything with a 20 ga fully rifled, other than Sabots? How about Truball in a smoothbore 20ga? I have a 20ga paradox (vintage) that shoots 500 gr conicals (NEI mold) quite well but I have to keep them at around 1000fps or they strip the rifled choke, even when hardened up a little. Trajectory is terrible. I did shoot an Eland with the gun in Botswana in 2002 and it was quite something to see 2000lbs of meat bite the dust within 40 yards of being hit.

I'd certainly like to hear more about your paradox gun, especially if you can post a few images.
I'd heard of the 12 bores like this but not the smaller gauges.

[peter nap]

I've done a lot of work with this concept and so has Blammer.

Basically saying I’m standing on the shoulders of giants or something like that - You get the idea.

Considering the work you've done Turbo, I'd say you underestimate yourself.....but that expression sums up my exact feelings about my experiments.

[vh2q]

Paradox guns were made in 10,12,20 and even 28 bore. The smaller bores are rare. The one I have started life as a 577BPE by Blissett, bored out to 20ga choked (thanksfully they left the sights intact), then finally rifled choke. I didn't have to reregulate the gun! The right choke is a little more open than the left, hence the rifling in the right is not as deep as the left, and they go astray if you load them too soft or too high velocity. I settled for moderately hard at 1000 fps.

I did once come across a 20ga paradox by Simson, sold it to Dave Weber (double gun bbs).

I have a 12 ga Fosbery Paradox hammer gun by H&H, as well as a 12 ga hammerless Chas Lancaster "Oval Bore".

Many makers offered paradox guns. I have owned them by Horton (Scottish), I Hollis, H&H, Simson, Lancaster. WR made them, as did Cogswell. I have a line on a coggie, but it's in Zimbabwe.

[vh2q]

Thanks Turbo.

Couple of q's. Any idea what pressure you are getting with R17? I am thinking along the lines of a 20ga sxs gun, fully rifled, probably not as strong as the NEF gun you are using. It will be a modern boxlock action, monobloc construction. But I don't think I want to go much higher than 15000 psi with it.

I have a 12 ga sxs fully rifled that I built on a Lefever action, and it shoots Lyman "in-wad" Sabots at around 1500 fps quite well using one of the recipes that came with the Lyman "pellet" mold. Regulation was tricky but I finally got them to shoot in the same place.

My son has an 870 pump in 20ga w. a factory fully-rifled barrel. Any suggestions as to full-bore slug loads for it? I have a 20 ga paradox mold (.625 or thereabouts) that I bought from NEI before they went sour. Would like to use that bullet if I can. We will be going to Zim this year on a bird hunt but I would like to take some slugs for warthog, impala etc.

I have contacted Dixie Slugs for info on their new 20ga ammo.

[Greg5278]

I think you could also have a .58 cal Minie ball mold opened up a bit, and use the CSD wad from BPI. The cushioned steel driver wads are unlslit, an tough enough to take the rifling. I use them in my 12ga. You would have to measure the shotcup thickness to get the right diameter for the mold. I make mine a .005" crush fit over bore diameter. So if you bore is .615, then the bullet in the wad should be .620"

The wads can be slit if you want a discarding Sabot. I do not slit mine, and they will go right through the target as a stabilizing tail.

PM me if you need some more info.
Greg

[turbo1889]

Thanks Turbo.

Couple of q's. Any idea what pressure you are getting with R17? I am thinking along the lines of a 20ga sxs gun, fully rifled, probably not as strong as the NEF gun you are using. It will be a modern boxlock action, monobloc construction. But I don't think I want to go much higher than 15000 psi with it.

. . . . My son has an 870 pump in 20ga w. a factory fully-rifled barrel. Any suggestions as to full-bore slug loads for it? I have a 20 ga paradox mold (.625 or thereabouts) that I bought from NEI before they went sour. Would like to use that bullet if I can. We will be going to Zim this year on a bird hunt but I would like to take some slugs for warthog, impala etc. . . .

I don't have pressure testing equipment but if measuring head expansion with a micro-meter and using published load data in the same exact hulls from the same exact bag as a control factor can be trusted the loads are about 9-K peak pressure. So they aren’t hot loads in terms of maximum pressure, however, it should be noted that my experiments, Hubel's (12GAFH guy) experiments, and my GF's (who posts under the name of tommygirlMT) experiments with using R-17 powder in shotguns for slug and ball loads has shown that the pressure curve of such loads is substantially different then regular shotgun loads. Regular shotgun loads burn up all the powder in the first few inches of the barrel length and this is where pressure spikes. From then on the payload is basically coasting for the rest of the trip down the barrel being driven by the ever decreasing residual pressure of the main burn which took place in the first few inches. By the time the payload clears the muzzle in a regular load the pressure has dropped down two only a couple thousand psi. This is not how it works at all with R-17 loads, the powder burns for the entire length of the barrel and pressures stay high for the entire length of the barrel. Hubel has recorded muzzle pressures of 5-K with his extra long barrels and I'm sure with regular shorter length barrels its even higher then that. Considering peak pressure is only in the 9-K range we are talking about still having at least half the peak pressure or more at the muzzle.

Thus in conclusion the safe use of R-17 loads is not determined by the strength of your gun or action as it is commonly know. If a gun's action is strong enough to handle modern full pressure smokeless loads it can more then handle R-17 loads. Rather it is a question of how thick the metal is on your barrel at the muzzle. Many shotguns have a tapered outer profile to their barrel - as you get closer and closer to the muzzle the wall thickness of the barrel gets thinner and thinner until at the muzzle it is barely as thick as thin sheet metal. With regular shotgun loads this works just fine because the barrel doesn't need to be very strong at its end because internal pressures are very low by the time the payload reaches the muzzle. With R-17 loads this is not the case - thus R-17 loads for safety reasons should be considered "Bull Barrel Only Loads" its not a question of the strength of the guns action but rather a question of barrel wall thickness. Both Hubel and myself have come to the conclusion that for safety the minimum wall thickness of a guns barrel at any point (usually thinnest at the muzzle) should be 0.10" for the safe and sane use of R-17 slug loadings. This can be easily measured with a caliper at the muzzle of many guns or alternately the outer diameter of the barrel can be measured, it should be at least the inner bore diameter plus 0.20" (0.10" twice over).

For guns which don't have enough barrel thickness near the muzzle to use R-17 loads I recommend Steel powder for 12ga. and 2400 powder for 20ga. using Fed-209A primers exclusively for both to produce maximum power loads with full bore slugs.

Your 0.625" NEI 20ga. paradox mold should work just fine provided it was a good slug design to start with. Picture or mold number so I can go look it up on the NEI catalog?



I think you could also have a .58 cal Minie ball mold opened up a bit, and use the CSD wad from BPI. The cushioned steel driver wads are unlslit, an tough enough to take the rifling. I use them in my 12ga. You would have to measure the shotcup thickness to get the right diameter for the mold. I make mine a .005" crush fit over bore diameter. So if you bore is .615, then the bullet in the wad should be .620"

The wads can be slit if you want a discarding Sabot. I do not slit mine, and they will go right through the target as a stabilizing tail.

PM me if you need some more info.
Greg

Excellent idea Greg I'll have to try that one myself.

[Greg5278]

Turbo, I made a mistake. The Mold to be used for the CSD wad should be a Lyman 548657, possibly modified to a hollow point. That should lessen the weight to a bit less than 400 grains
Greg

[vh2q]

The NEI 20 ga mold I have is #398A "Westley Richards". I don't hollow-point it, so it casts around 500 grains. WR made a 20ga paradox gun called the "Fauneta" I believe, hence the label. This was from the Walt era at NEI.

[turbo1889]

That should work just fine, especially if its an older one that Walt cut. The only real annoyance I see is that the length of the nose will probably make roll crimping a PITA.

[vh2q]

That should work just fine, especially if its an older one that Walt cut. The only real annoyance I see is that the length of the nose will probably make roll crimping a PITA.

I use Rem ribbed cases ... they are thick enough and tight enough to grip the (.625") bullet firmly without any crimp at all. I tried brass cases, they looked slick, but they are too thin and after a couple of reloads they split. Maybe those Red River brass cases would work better.

[turbo1889]

. . . . Maybe those Red River brass cases would work better.

Huh! What! Did I just hear that there is another source of full length brass shot shells out there besides Mag-Tech and Rocky Mountain Cartridge, LLC that I don't know about yet?

Details please - website, contact info, etc, etc.

By the way, the ones from RMC are real nice and thick and will probably last forever. They are strong enough you can stand on them. I've also heard rumors of thick walled aluminum ones out there as well but have yet to see one or get a source - not even a posted picture so far.