André,

I am certainly no expert, but I would change nothing pending test results. I like the looks of those bullets!

I would expect the cup point to initiate moderate expansion quite nicely, given that the bullets are pure copper. And we must remember, these slugs are .510" in diameter to start with.

I can't see how a hollow base would add anything positive that would be worth the trouble.

So I say damn the torpedoes and full speed ahead!

quote:

Originally posted by jeffeosso:
when results can be repeated, and are documented, and subject to peer review, it is far more scientific than some other of our penetration "tests"

Andre, great looking bullets, however your design raises many questions of terminal performance, expansion, and penetration. If you wanted merely a 10 post thread on the bullets looks/design, there is a bullet making forum.

but, if you want to discuss the various opinions on how bullets perform, this appears to be the correct forum.

LOL .. myth busters not proving anything? should we apply that to 99% of the "facts" running around the internet and AR, we would feel nothing has ever been proven, period

Ja I know but still.
I posted in this forum to get more responce about the design.

Boom stick
I will make the cup deeper.

I do not know if the bore rider function on the front of the bullet playes a big part. I do however know that if the bullet is not bore caliber in the front part the bullet will not be heavy in the front and that is important if I want the bullet to be directed by the front after the bullet enters the medium.
The bullet expands a bit and becomes more haevy in the front. Just like a soft nosed bullet but just with very little expansion.

Cheers,

André

quote:

Originally posted by mrlexma:
André,

I am certainly no expert, but I would change nothing pending test results. I like the looks of those bullets!

I would expect the cup point to initiate moderate expansion quite nicely, given that the bullets are pure copper. And we must remember, these slugs are .510" in diameter to start with.

I can't see how a hollow base would add anything positive that would be worth the trouble.

So I say damn the torpedoes and full speed ahead!

Ja you are right.
I will send some your way and you can load some up with whatever powder you Yanks use
I will load with Vithavouri N140

Cheers,

André

..........Andre.,., My minor thots on the first pics of your bullets .....If the area foward of the grooves is less than bore dia it will help elimanete high chamber pressure problems .....I myself prefer the rounded shoulder as it will greatly assist in gettins a bullet in the barrel insteafd of a bunch of frantic jerkin and slammin and lookin ... which in the real world .,is the reality ..for all of my purposes I would like the ability as 500 gr stated , of haveing the cup [ mushroom] back once it was inside the animal.....in mho I think that if the base of the bullet was able to obturate and there by help to keep the gasses behind the bullet it should lead to less gas cutting of the leade and rifleing ..so to review my thots ,[the identicle nose and nose cup shape and size to aid in chambering a round ],[front of the bullet less than bore diameter ] [ lots of grooves, to crimp different rifles and cart.s where desired , and to reduce friction a little ] [ a cup base to aid in stability and seal the bore. [ and lastly a coateing to keep the bullets from corodeing inside the case neck and after time and exposure to salt ..]..........But even as is your bullets make me want another 500 A2 ..How about other calibers ??? 475 / 458 /416 /375/9.3 ....I appreciate your time ........gumboot....I can,t spell so good ,.sorry .

Andre',
This Yank would stoke it up to 2500 fps with Varget or RL-15, or maybe H4895.
If it shoots accurately in a 500 Jeffery or 500 A-Square and feeds well, it is bound to get the job done.
Shoot game large enough to stop that bullet and you should have boringly reliable performance with a large copper cup nose like that. Dead right there.
The only problem would have to be cracks in the copper, to be blamed on bad copper supplied by Walter to the machinist, should a scapegoat ever be required.

gumboot458

Thanks for the imput.
More groves for different loads You got it. many vintage .500 Jeffery's are made on a standard Muser action and will not accomadate theis long cartridge.
When the design is right I will make these bullets in other calibers, 375 H&H .470 NE and 458 maybe others if the demand is there.


RIP

Sounds cool with those loads, you can take the kick I know
Hey this is Europe we do not use bad copper

You got a batch coming your way.

Cheers,

André

I have no doubt that bullet will work fine so don't misread my thoughts..

I have noticed that when you shoot an animal such as a bear or any animal with heavy hair that the cutting shoulder that cleans the area of hair gets a better blood trail as the blood spurts out whereas with many soft nose and round nose bullets solids or whatever the blood matts with the hair and the blood trail is lean in many cases..

Elmer Keith proved all this to be right with his simi wadcutter in pistol rounds many years ago, and it has worked for years, now the experts have found disagreement with old Elmer. I am not sure who is right or wrong but I will stay with the Bridger solids and Northforks solids or cup points with a cutting shoulder until hell freezes over!

Andre'

I toyed around with modifying Original Barnes Mono RNs in my .458 Lott using a water trap as test media.

One modification type was to drill basal cavities in the attempt to move the Center of Mass forward of the Center of Form. For insurance, I calcuated the amount of mass needed to be removed, did a rudimentary balance check of the modified bullets, and drilled two more cavity depths beyond the calculated requirement.

Upon firing into my water trap, none of the modified bullets remained stable despite the wieght forward configuration. The other, perhaps more important, bit of information that I learned was that this design caused heavy bolt lift, very sticky extration, and case head flow with normal powder charges. Apparently, the .300" diameter cavity causes bullet obturation, increased in-barrel friction, and excessive pressures.

Although an inverted cone basal cavity, similar to your nose cup, might add a slight stability benefit without pressure issues, I doubt the stability will be noticable better and a basal cavity will only add more manufacturing variables. If it were my bullet, I'd stay with the boat tail/flat base design.

Your original version has all the right compromises and gets my vote!

..........That is interesting the results pws had so much for the expanding base design ..PWS did you chronograph any of them ...Thanks ...

quote:

Originally posted by PWS:
Andre'

I toyed around with modifying Original Barnes Mono RNs in my .458 Lott using a water trap as test media.

One modification type was to drill basal cavities in the attempt to move the Center of Mass forward of the Center of Form. For insurance, I calcuated the amount of mass needed to be removed, did a rudimentary balance check of the modified bullets, and drilled two more cavity depths beyond the calculated requirement.

Upon firing into my water trap, none of the modified bullets remained stable despite the wieght forward configuration. The other, perhaps more important, bit of information that I learned was that this design caused heavy bolt lift, very sticky extration, and case head flow with normal powder charges. Apparently, the .300" diameter cavity causes bullet obturation, increased in-barrel friction, and excessive pressures.

Although an inverted cone basal cavity, similar to your nose cup, might add a slight stability benefit without pressure issues, I doubt the stability will be noticable better and a basal cavity will only add more manufacturing variables. If it were my bullet, I'd stay with the boat tail/flat base design.

Your original version has all the right compromises and gets my vote!

PWS

Thasnks for the information.
I will stick to the boat tail and flat base design.

Maybe next week I will get time to go the the shooting range and test them.

Cheers,

André

Gumboot,

I didn't chronograph any of the loads I'd fired into my bullet trap. As it was, I had a big dock with about 20' of water available below it (depending on tide). There's a float dock with a ramp riding the pilings on one side so I'd sink the trap over the floater, run up to the main dock, and fire down into the trap. Too much trouble to set a chrono in line. I'm guessing all loads were in the 2200fps ballpark though as the modified bullets were in the 450-500 grain range and the load was 80 grains of H4895 in a 23" .458Lott.

Perhaps a stronger bullet material would work with a basal cavity? Copper clad steel? Again, I doubt it's worth the trouble.