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w30wcf
11-19-2005, 08:54 AM
After success with the .06" thick polyethylene wads under the 311241 plain based bullet at 2,000 f.p.s., I decided to try a lighter bullet at higher velocity to see what would happen.

I had purchased an older Ideal 308245 on Ebay this past year and for this experiment, I made some from Linotype. This bullet was originally designed for Armory range use (100 to 300 feet) in the .30-40 Krag back around 1900. It has 2 grease grooves and a dirt catcher groove in front of the first driving band. My mold dropped bullets at 88 grs. in Linotype. I sized them to .311 and filled all three grooves with M&N lube.

The test rifle would be my 26" barreled 1894-1994 WInchester Centennial Rifle, the same one used in testing the 308241 bullet / poly wad at 2,000 f.p.s. This rifle wears a tang sight.

Previously, using REL7 powder and 93 gr. .30 Luger jacketed bullets, I was able to achieve 3,000 f.p.s. with 50 yard groups of < 3/4" with this rifle.

To start with, I used a load of REL7 powder that developed about 2,850 f.p.s. under the 311245 bullet / poly wad combination. This combination shot well at 50 yards producing a 1" group.

Increasing the powder charge, the chronograph recorded an average of 3,027 f.p.s. and the bullets grouped into 1 1/4" at 50 yards.

I was elated to say the least.

I also tried upside down gas checks (sized .312) instead of the poly wads, but interestingly, group sizes were much larger at 3 1/2" (50 yards). Apparently, for this use, the support of a bullet shank would be needed for a better seal.

In this particular application, the poly wads did a superior job of sealing the gas behind the bullet, allowing for accurate shooting.

I'll make more bullets this winter for more experimentation come spring.

Happy THanksgiving,
w30wcf

Bass Ackward
11-19-2005, 09:51 AM
Big Three O,

Great experiment. Sounds as if maybe pressure affecting the base is the failure reason. In that cartridge, RL7 to an 88 grain bullet might equate to 4831 with a 188 grain bullet. Follows on my thoughts that the highest velocities with any caliber comes with lighter weight bullets especially if you have the "right" throat to shoot them.

44man
11-19-2005, 09:57 AM
I have never discussed how fast lead can be shot before but always had the idea that they COULD be shot at high velocity. There are several reasons you have been able to do it. First of course is the very hard lead that allows it to take the rifling better. Not practicle for hunting though as it would just shatter on game.
Second is the light weight of the boolit. A heavy boolit would have so much inertia that it would resist spinning and be more apt to strip before it got started.
I have to question how the poly wad is acting if your boolit fits the throat and bore. The next thing you have to do is to load some without it and see what happens. They might shoot just as good. Please try it and post again.
As far as upside down gas checks, I have tried them in revolvers and never had good accuracy. I believe that at the moment they leave the muzzle, while still in contact with the boolit base, that they skew sideways due to the upside down cup and slightly tip the base of the boolit. Then the question arises of what happens if the pressure does not impact it evenly and one side deforms the boolit base, ruining it and the whole thing going down the bore with the base a little tipped? Remember, the powder is laying sideways in the case and the build up of pressure can be one sided. What we need are a bunch of high speed photos to see exactly what happens. Also in a revolver, what happens to the gas check when it hits the forcing cone? One clue I had was that the upside down gas checks were almost never straight downrange when I looked for them. They were scattered in all directions and at all distances, unlike the poly wads which were right out in front.
Another interesting experiment would be to punch a hole out of the center of the GC, put it upside down in the base of the mould and cast through it. I would anneal these first so they are soft. The lead would not stick good to them but the cast button inside of it would hold it to the boolit base. Would they flare for a good seal, and take the rifling better?
Another idea would be to try the whole test again with heavier boolits.
This is getting to be fun thinking of all the things to try. I wish I still had a rifle to play with. Keep us posted with your trials.

jh45gun
11-19-2005, 10:00 AM
So what are these poly wads?

StarMetal
11-19-2005, 11:44 AM
Bass,

Gosh, the highest velocity with any caliber will come with lighter bullets. Duh. The faster anything in the world is with the lighter whatever it is: airplane, race car, bullet, boat, etc. I had to laugh at that one...sorry.

Joe

D.Mack
11-19-2005, 11:46 AM
44 Man, The hole in the center idea, has been tried. They were called "Wilke checks" for checking plain based bullets. When the hole is centered, and big enough for proper fillout they work. Another version was copper tubing cut to fit one of the driving bands. The problem was consistancy, as I was never able to make the effort worth the trouble. D.M.

44man
11-19-2005, 08:34 PM
D Mack, I know about those checks, but I was talking about reversing the check so the flare is towards the powder. It's been so long that I read about the Wilke that I forget how they were put on or what the shape was. I remember a lot of checks that were just a flat disk. One was made of zinc but I don't remember the name. Harvey something or other.

Buckshot
11-20-2005, 07:01 AM
...........A very interesting test. A couple months ago Glen, one of the burrito shooters had cast up or come across some Ly311440's. Some he couldn't get a GC to go on so they were loaded without a GC. The others had a GC. He'd loaded these up over 20.0grs of Lightening.

As I walked past his bench on the way to fetch lunch he remarked about how poorly the boolits with the unprotected bases were fairing. He was shooting at 50 yards and I believe he said the group was like 6" or so?

He said, before you leave, let me shoot some with the GC's to see what happens. Well I suppose you can guess what the difference was. He fired 5 rounds in rapid succession with all 5 going into the 10 ring.

http://www.fototime.com/0EC721E256DE02F/standard.jpg
This is a NLA Saeco schuetzen plain based tapered .336" boolit of 208grs I'd bought to shoot through my M95 Steyr 8x56R. Sized to .335" it shot very well to about 1200 fps. Much more then that and they just sprayed all over.

On the right is the same slug with a 35 cal GC swaged on. These shot to a bit over 1600 fps before scattering.

................Buckshot

Bret4207
11-20-2005, 09:12 AM
Good, informative comment Joe. Thanks for your contribution.

w30wcf
11-20-2005, 09:34 AM
Bass Akward,
Interesting comparison. I had not thought of it that way but it makes sense.
A capacity load of 4831 ignited by a magnum rifle primer will do 2,000 f.p.s. in the 26" barrel with a 200 gr. bullet.

44 Man,
"Not practicle for hunting though as it would just shatter on game."
It would be interesting to try it on varmints at close range though.

"Second is the light weight of the boolit. A heavy boolit would have so much inertia that it would resist spinning and be more apt to strip before it got started." That may be true for some bullet designs, but I have pushed 160 gr. g.c. bullets to 2,600 f.p.s. from my Rem 788 bolt action .30-30 (10" twist) into 1" - 1 1/4" groups at 100 yards. The alloy must be hard enough to stand the torque / pressure.

"I have to question how the poly wad is acting if your boolit fits the throat and bore. The next thing you have to do is to load some without it and see what happens. They might shoot just as good." Based on a test I did with a 100 gr. RCBS plain based bullet several years ago, trying to see how fast I could push it before accuracy started to really deteriorate (1,800 f.p.s.), accuracy without the poly wad would be non exsistant and I might just get a bore full of leading. Good thought though.

Thank you for sharing your experience with the upside down gas checks. Sounds like a good reason they didn't work as well. Rather than putting the gas checks into the mold with a hole in them to cast through, i could turn the back driving band down in my lathe and put a gas check on them that way. Another experiment...............

"This is getting to be fun thinking of all the things to try. I wish I still had a rifle to play with." Yes, it is fun. Time to get yourself another rifle!

jh45gun,
They are .06" thick low density polyethylene discs. Please see the other "plain based bullet" thread for links.

Buckshot,
Thanks for sharing. Interesting.

w30wcf

felix
11-20-2005, 10:47 AM
This thread should be merged into the other one with the same subject. The thing that should be emphasized is that making a boolit tough is the goal (zero shear) in all applications. The boolit hardness, the ability to shatter or mushroom, comes into play per application. Toughness first, hardness second. Always. ... felix

canuck4570
11-22-2005, 08:19 AM
if I understand right ... theire must not be any air space between the bullet and powder... I phoned Buffalo arms to order a wad punch and they said this is a no no.....only with black powder....

w30wcf
11-22-2005, 01:59 PM
canuck4570,

The good folks at Buffalo Arms could be concerned about someone using the poly wad to hold the powder in place in a less than a capacity smokeless load. That would definitely be a no-no since there is a good chance to ring a chamber if the wad collides with the base of the bullet.

As long as the wad is large enough in diameter to stay in contact with the base of the bullet when seated over a less than capacity smokeless load, that is aok and works very well.

With black powder loads, yes, for best results there should be no airspace between the powder and the bullet or under the wad/bullet if a wad is used.

w30wcf

45 2.1
11-22-2005, 02:10 PM
Charlie Dells book about the Scheutzen Rifle has a good amount of testing results about wads on and over powder.

13Echo
11-22-2005, 04:15 PM
Col Harrison from the NRA had good succes with paper patch, plain based bullets at over 3000fps from a Win .300 mag. The article is in the NRA Cast Bullet book. Very interesting read, especially since he got decent 100yd accurac, at least as good as jacketed in the test rifle.

Jerry Liles

canuck4570
11-22-2005, 06:56 PM
thank you for your experience.... I intend to push my 500 gr in my 4570 at about 1500 fps and I will be using slow burning powder.. my 500 gr bullet sit most of it lenght inside the case almost .780 so I will make shure the powder make a small compression on the wad and bullet.