Speer Grand Slam bullet ID

[Potashminer]

I have been reading various forums how Speer changed up their "Grand Slam" bullets a "few" years ago. The original, at least in 30 caliber, had two cores - a hard alloy to the rear and a softer alloy to the front. I am reading that some years ago this was changed to a single alloy throughout.

I have three different packages in my stash. Maybe more exist? Of the three shown in the pictures below, does anyone know how to tell which are the "old" style with the dual cores, and which are the "new style" with the single core?? If I was to section these bullets, would I see the two cores or are they continuous?? Thank you for assistance.

EDIT: On closer examination - the 3 boxes with the yellow labels (top box in pictures) have bullets with two cannelure grooves; of the 7 boxes with grey/black labels (middle ones) 2 boxes have 2 cannelures - 5 boxes have one cannelure. The bullets in the one black label box that I opened have one cannelure. I do not know if that is evidence of a difference or not.

View of end of packages - note the top two packages have the HotCor flame symbol (top box's is partially hidden - red flame in black circle) - the bottom one does not have to HotCor symbol:



Same boxes, in same order - view of top of the packages:

 

[9.3mauser]

The top, smaller sized box is older, I think the middle, transparent box is too, the black box is newer. I'm not exactly sure when the change was made. If you section one you might see a difference in the colour of the lead.

 

[Longwalker]

The top box is almost certainly the original and "best" version, dual core with inner ring to keep core from slipping. Center version is during the transition time. Might be either one, but I'd feel reasonably confident it was the pre-change version. Bottom box is pretty much the Speer Mag tip design with a nicer package and graphics.
I've shot a lot of game with Grand slams. And some with Mag tips. Grand slams in their original version were really good in my .308, 7x57mm, and .35 Whelen for big stuff like elk. Either version is a very good deer bullet.

 

[Potashminer]

So, I did just section two bullets from middle boxes - one with and one without the second cannelure groove. No evidence that I can see inside of different cores - if there are two hardnesses, they are not visible - the only "ridge" inside the jacket matches up with that major cannelure groove.

Edit - and just sectioned one from the top yellow label box - if there is two different cores, certainly not visible to me. If there is a "ring" does not appear to be different than the indent on inside at the cannelure?

Was thinking about that HotCor symbol - if the two cores were molten when inserted, they would blend? Would be no "seam" like I was expecting, and not seeing??

 

[Potashminer]

My intent on building up this stash was for various rifles in 30-06, 308 Norma Mag, 300 Winchester and a lone 300 Weatherby. I find the 308 Win and 165 grain (Speer HotCor) and the 7x57 with 150 grain (Partitions) have done everything I wanted - so was thinking 180's for the bigger cartridges. Maybe too naive - was hoping for a "one bullet" for coyotes to moose, if needed, for any of those 4 rounds. Gonna just have to keep the packaging separate, keep track of which is which, and go shoot stuff and see how they work!!!

 

[Hitzy]

They also have a heavier jacket, wouldn't worry too much about the dual core thing, especially with 180's.

 

[Ruger007]

The top is probably the 2 core. As they changed later in that box style. Bottom ones are not dual core.

The dual cores are known to be not as accurate. Due to the first core of heavier lead mixing inconsistent with the second hot core.

Either way they are great bullets. Originals were a poor man's partition.

Newer ones still have the heavier jacket.

My 6mm loves the 100gr.

Unless you can cut it nicely and etch them. Hard to tell.

Dual cores were in the .257 and up. Not the .243

 

[Boomer]

So here's a thought. Put any resizing die in your press and your sectioned bullet across a small cartridge shell holder. Raise the ram to the top, then thread the die down until the decapping pin just touches the bullet core at the rear part of the sectioned bullet. Back off the ram slightly and turn the die in an eighth to a quarter turn, then run the ram to the top of the stroke. Repeat with the front section of the bullet, and the indent with the more material displaced is the softer alloy. If the indents are similar, so its the hardness.

 

[Longwalker]

Or, just keep it simple. Any of those bullets will give satisfactory results on game when shot from a .30-06. I'd shoot the newest version, black box in the .30-06, and save the orange boxed bullets for the magnums. I strongly suspect but can't prove the two cannelure vs one cannelure is when the internal construction change took place. In your magnums, I suggest you use "two" for tough game like elk, "one" for smaller softer deer size game and target / practise shooting. Easy to identify by looking too. There is nothing actually "wrong" with the new, simplified version of the Grand Slam, I doubt that you'd actually notice the small differences in construction in field results on game in a lifetime of hunting. In my opinion either version is a much stronger, clearly superior choice for large game / magnum cartridges vs popular, more frangible bullets like Sierras or Bergers or SST's.

 

[Potashminer]

Thank you for the replies - good comments / suggestions above!! At my age, there will not be many more rounds expended at game, in the rest of my "lifetime" - so probably more a "curiosity" thing than anything "practical". No doubt, I will take the Ruger No. 1 in 7x57 with 150 Partitions if I go looking for a deer; my 338 Win Mag or more likely my 9.3x62 for bigger things, if I need more than that 7x57. And if I can only keep "one", it would be one of the 30-06's - probably the Win M70 made in 1955 - same year that I was!!!

 

[Longwalker]

So many rifles, so little time... I have the same "problem" ;-)