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Plain base bullets and leading
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Picture of John Y Cannuck
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Just thought I'd get some views on what velocity leading starts for you, without gas checks, and what hardness you are using.
I recently fired a 45-70 340gr at 2175fps with wheelweight bullets hardened only by dropping them into cold water. The result, predictable, was streaks from chamber to muzzle. I have little trouble with that bullet loaded at 2000fps, and below (alox lube). Now the barrel is a Douglas premium, and thats real pretty when clean so maybe that has a bearing on why I can get to 2000? Let's hear your thoughts.
 
Posts: 872 | Location: Lindsay Ontario Canada | Registered: 14 April 2001Reply With Quote
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quote:
Originally posted by John Y Cannuck:
Just thought I'd get some views on what velocity leading starts for you, without gas checks, and what hardness you are using.
I recently fired a 45-70 340gr at 2175fps with wheelweight bullets hardened only by dropping them into cold water. The result, predictable, was streaks from chamber to muzzle. I have little trouble with that bullet loaded at 2000fps, and below (alox lube). Now the barrel is a Douglas premium, and thats real pretty when clean so maybe that has a bearing on why I can get to 2000? Let's hear your thoughts.

Be be sure- your barrel Q is helping produce those speeds, but as you describe the symtoms the leading is originating per gas blowby at the throating. Most likely accuracy is due to the barrel uniformity internally coupled with the hard bullet from quenching. So if you increased the gas seal, makes you wonder if your leading would disappear?

You didn't mention powder # whose speed relates to chamber pressure. The slowest fuel producing that desired speed would give some advantage too.

My 45/70's limit which I haven't investigated much was 1640's with Lee 405's pushed by Alliant 7 topped with Bf filler. Those slugs were aged air cooled ww alloy at 459 in a 456 bore. The only leading was from shearing-- the bullet just starting to loose grip of the rifling. This due to a bore with a reverse taper, getting larger from the throating to the muzzle end. Worst thing for a cast bullet. Still shot just over 3" though which surprised me. I'm in the process now of lapping this bore to a uniform dimension end to end.

I've talked with advanced cast experimenters who shoot PB very fast-- using a very hard bullet fitted exactly to the throat dia. Various things are used to seal all combustion gases from going around the slug-- no gas erosion up the bullet sides means no leading, provided the bullet will hold the rifling.

So- I think the speed limit is a product of your gun's quality and how far you want to tinker with the setup.
 
Posts: 1529 | Location: Central Wisconsin | Registered: 01 March 2001Reply With Quote
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I have had good results with harder bullets than you describe.The alloy i used was 50/50 WW and lino ,also dropped in water. This and dacron fibres on top of the powder gave no leading up to 2300 fps in a 375 H/H. Make sure that the barrel you shoot your cast bullets in ,are free from any jacket fouling!!
Firelapping a barrel Should also improve its quality for shooting lead althoug that should not be nescessary with a douglas barrel.I haven`t personally tried it in a rifle but have freqently done it on S&W revolvers and it really helped a lot.
You mentioned alox lube and i know that it works for some , but i never had any decent results with it, so after a lot of experimenting with all kinds of sticky stuff , i settled for LBT blue which i believe is still sold by Veral Smiths wife. I bought around 5 lbs. of it before he got in "trouble".
Maybe you have reached that particular bullets limit in that particular barrel with that alloy but i think you can stretch that limit a bit by using a better lube , make the bullet a bit harder and maybe size it .001" bigger (have you slugged the barrel ? ).If i size too small i get terrible leading in all types of barrels.
I`m sure that with the right combination you could reach around 2300 fps without a trace of lead in the barrel . GOOD LUCK
 
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<reloaderman>
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Just a thought.....how about bullet lube? I've shot .30 cal bullets @2200-2300fps without leading in my 30-40. I use Midway's mold release!
That's Midway's Drop Out!
It comes in a spray can, and all you do is stand up the bullets and spray them, no other lube is needed [Wink]
Try it....it works [Wink]

[ 09-05-2002, 05:42: Message edited by: reloaderman ]
 
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Well I not even coming close to that.

416 Rigby:350gr plain base #2 alloy dropped in water, alox lube ,powder XMP5477 ..55gr 2173ft/s lots of lead.
46gr 1850ft/s lots of lead // 30 gr vel ? 1" 5 shot @100y no lead.

500AS :550gr plain base #2 alloy dropped in water,alox lube,powder XMP 5477..45gr vel 1450ft/s no lead 1.5" @75y open sights no lead.

Paper patch so far 60gr vel 1850ft/s

Oneshot, you don't happen to know how to contact Mrs Smith do you?
Regards Martin
 
Posts: 319 | Location: Alberta Canada | Registered: 25 June 2001Reply With Quote
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Originally posted by Martin@Hin:
Well I not even coming close to that.

416 Rigby:350gr plain base #2 alloy dropped in water, alox lube ,powder XMP5477 ..55gr 2173ft/s lots of lead.
46gr 1850ft/s lots of lead // 30 gr vel ? 1" 5 shot @100y no lead.

500AS :550gr plain base #2 alloy dropped in water,alox lube,powder XMP 5477..45gr vel 1450ft/s no lead 1.5" @75y open sights no lead.

Paper patch so far 60gr vel 1850ft/s

Oneshot, you don't happen to know how to contact Mrs Smith do you?
Regards Martin

Martin it's doubtful any lube is going to get you to those speeds [>1600 fps] sans leading with PB bullets. At those chamber pressures your alloy isn't strong enough to resist gas cutting/erosion up the bullet sides. And it's doubtful your getting much hardening of the bullet dropping #2 alloy into water per the amount of tin present.

You might be able to boost those speeds minus leading by using a slow fuel and something to protect the bullet base, along with a harder bullet. Idea is easing the bullet into the barrel using a full case of slow powder and/or filler to uniform combustion.

There's a fella @ Shooters.com's cast forum named Bruce B that shoots a 416 amongst other cannons. A post around those parts might find some details to line up your 416's performance.
 
Posts: 1529 | Location: Central Wisconsin | Registered: 01 March 2001Reply With Quote
<oneshot>
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Martin:
I read in in one of the threads on this forum that Mrs.Smith was still selling the LBT lube and i think maybe also the book ( Jacketed performance with cast bullets )which i consider to be the best ever written on this subject.
Unfortunately i didn`t write the add. down but i have his old add. : Lead bullets technology. HCR62,box 145. Moyie Springs, ID 83845.
Hope it will help you .
Karsten.
 
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Oneshot
You may have caught what I missed. The load was compressed Rel 7. I dropped the Dacron wad I had been using for powder room.
 
Posts: 872 | Location: Lindsay Ontario Canada | Registered: 14 April 2001Reply With Quote
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Martin :try this one for ordering LBT stuff . http://www.sixgunner.com/FAQ/lbtbook.htm
John Y. C.: Although many have adviced me to use slow or medium slow powders with lead in order to push and accelerate the soft bullets gently and maybe even at lower temp.it just doesn`t seem to work always and i have no explanation! it could be the dacron as i have tried to shoot H110 and VV n110 without the fibres with poor results and yes i did make an issue out of having the powder rest close to the primers ,i even used cornmeal as a filler! no good and too messy.
Karsten
 
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Aladin/Karsten:

In the grey past I talked to Bruce about this but I believe he uses gas checks.
V Smith talks about slow powders and poly fillers, he also state's that 60% or more of the case volume needs to be filled with a slow powder.
In cases like the 416 and 500 we are talking at least 60 to 70 grains of powder.
The next question is which powder to use, they always say :don't reduce slow burning powders.
The powder company's are no help in this matter I asked.
So is 4350 fast enough or is it 4064 or 3031 ???

I would like to play with it some but is not a big isue because it is nice to shoot thse guns with the reduced recoil.

Karsten, thanks for the add I will write them to find out if they still sell the blue lube.
ps. did you see the price of the pistol lube? enough to choke a horse.

Regards Martin
 
Posts: 319 | Location: Alberta Canada | Registered: 25 June 2001Reply With Quote
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quote:
Originally posted by Martin@Hin:
Aladin/Karsten:

In the grey past I talked to Bruce about this but I believe he uses gas checks.
V Smith talks about slow powders and poly fillers, he also state's that 60% or more of the case volume needs to be filled with a slow powder.
In cases like the 416 and 500 we are talking at least 60 to 70 grains of powder.
The next question is which powder to use, they always say :don't reduce slow burning powders.
The powder company's are no help in this matter I asked.
So is 4350 fast enough or is it 4064 or 3031 ???

I would like to play with it some but is not a big isue because it is nice to shoot thse guns with the reduced recoil.

Karsten, thanks for the add I will write them to find out if they still sell the blue lube.
ps. did you see the price of the pistol lube? enough to choke a horse.

Regards Martin

Martin I don't like the poly fillers myself due to the melting and coating the bore. I use bran fiber or Bf as I've designated it-- doesn't melt and clear the bore readily with enough compression. I use Bf even with shotgun powders in 30/30 and 06-- filling over half the case with it.

As to the powder speeds-- no one could give you a definitive answer. SEE is rare and the exact circumstances producing such aren't readily known around shooting circles. You could do as alot of cast shooters do-- load a caseful of very slow surplus powder. If that large case would utilize it efficently and accomplish a reduced loading is the question.

I have downloaded 7828 in the 45/70 with Bf with no problems-- shot very well too. I think if that load is tight at ignition it curtails the chance of SEE.
 
Posts: 1529 | Location: Central Wisconsin | Registered: 01 March 2001Reply With Quote
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Aladin: V Smith state's in his book that the coating does not build up and helps lubrication and this way may help with the Vel.
Did you find this not so? I was not able to find the brand names he was talking about but I did find some shot buffer ,it's like dust and I wasn't sure about it.
As far as the powders I think I am going to give it a try with RL15 or 4350 and see what happens.

ps what exactly does SEE stand for? I know that it is the detination or irregular burning of gun powder sometimes combined with a ringed barrel.
Regards Martin
 
Posts: 319 | Location: Alberta Canada | Registered: 25 June 2001Reply With Quote
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quote:
Originally posted by Martin@Hin:
Aladin: V Smith state's in his book that the coating does not build up and helps lubrication and this way may help with the Vel.
Did you find this not so? I was not able to find the brand names he was talking about but I did find some shot buffer ,it's like dust and I wasn't sure about it.
As far as the powders I think I am going to give it a try with RL15 or 4350 and see what happens.

ps what exactly does SEE stand for? I know that it is the detination or irregular burning of gun powder sometimes combined with a ringed barrel.
Regards Martin

Martin I'm a Veral fan but not everything in that book is exactly correct for all situations. For instance, what happens to the coating when the barrel cools off? And different buffers have different melt points. Grex by Winchester is the agent he most used I think. Some of the newer buffers have rec'd favorable reports. I just found Bf cheaper, better at uniforming ES's albeit harder to meter with precision.

SEE= Seconardy Explosion Effect. The use of greatly reduced chg's resuling in excess unused case volume producing atronomical pressures. Usually seen with slow fuels-- it has happened with faster numbers too including 4895.
 
Posts: 1529 | Location: Central Wisconsin | Registered: 01 March 2001Reply With Quote
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Aladin:
Thanks so much for your help.
I looked in the kitchen cupboard and found some Bf and you are right the poly was $8. Can.
I started my day off today so I am going to play with it.

Regards martin
 
Posts: 319 | Location: Alberta Canada | Registered: 25 June 2001Reply With Quote
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