Home Forums Hunting & Shooting Ask The Gunwriters speer grand slam bullets

If they're just hotcors I'd still use them. Like the Speer BTSPs, too. They seem to have about the softest cores you will find, which makes them useful at distance. Never used a Berger or A-max, but probably like that, just less expensive.

In .375" the 270 gr BT has a nice ballistic coefficient. But after the first shot all rounds in the magazine are apt to become flat points. Kinda like Cinderella at midnight.

"In any case, I think even with core/jacket separation they will certainly kill whatever they are aimed at."

Sorry, but evidently you don't have much experience with jacket/core separations, especially on game larger than deer.

John - what do you think of the old 285 grain .375" Grand Slams? A buddy sold me a whole bunch of 375 bullets years ago including 35 of these. I've never tried the Grand Slams. I'm not sure how old they are, but it's one heck of an old plastic Speer box.

Thanks, Guy

I had a lot of bloodshot meat on 2 moose hi shoulder shot 35 Whelen 250 gr GS about 2500 FPS never saw that with the Speer hot core 250 Gr loads similar shot placement.

Guy, back when I knew the Grand Slams hold together I gave a buddy headed to northern British Columbia on a moose/grizzly hunt a box of them for his .375 H&H. They worked perfectly on a 50-inch bull, and the 8+ foot grizzly that came to claim the leftover moose parts a day or two later. Both bullets exited.

If you're curious about your particular batch, I would shoot a few into a stack of dry newspaper or old phone books and see what happens. As I posted earlier. I heard about Speer eliminating the dual-cores and requested a sample of 200-grain .30s, which came in the clear orange/plastic box Grand Slams had come in for years. 2 of 5 came apart in dry newspaper.

Do the new ones still have "GS" stamped on the base?

Well, John, you would be right. I don't have much experience with jacket/core separations on animals larger than deer. I believe those two elk with the Grand Slams were the only bullets that I've ever used on animals larger than deer where I found the cores and jackets in separate locations. But, both elk died, although they were shot more than once. I've also seen a couple of other jacket/core separations using Speer bullets in other calibers on smaller game than elk, but I don't recall the exact bullet. I don't have anything against Speer bullets and I continue to use them for deer and antelope. However, for elk, I think there are better bullets. That's just my opinion. I based my above statement that they will kill whatever they are aimed at on my experience that they killed the elk. However, I certainly don't have your experience with bullets or game.

I would ask you, though, respectfully, if you don't kill the animal, just how do you know that the core/jacket separation issue won't kill the animal? If you don't kill the animal, how do you know they separated?

Paul Fabian

I have seen 600-700 big game animals taken, along with a bunch of others skinned and quartered on hunts from North America and Africa Quite a few were shot with bullets where the core and jacket separated--and neither the core or jacket penetrated the ribs. This was because the animals were tracked down and killed--or the hunter got in a quick second shot.

One was a mule deer buck I shot at about 200 yards with a 150-grain .30-06 bullet--which broke the shoulder joint on a quartering-on shot, but did not penetrate the ribcage. Instead, only fragments of the core and the empty, flattened jacket were found lying against the ribs. A similar thing happened with another cup-and-core bullet, this time on a mule deer doe my cousin also shot in the shoulder joint, at only 100 yards. Luckily, the doe hobbled a few yards and he put another behind the shoulder, which penetrated. Again, we found the empty jacket and core fragments resting against the ribs.

Have even seen "bonded" bullets fail to penetrate because the bond didn't hold. One was a high regarded 300-grain premium, where evidently something went wrong during the bonding process. It was another quartering-on shot in the shoulder joint--but this time on a 1500-pound water buffalo. Again, the bullet broke the joint, but never made it through the ribs--which is where we found the jacket, with only a tiny bit of core attached, having lost half its original weight--and flattened out far wider than it was thick. Luckily, the hunter was backed up by a guy with a rifle loaded with solids, which slowed the buffalo down enough for both guys to put more shots into it. Only one of the several defective 300-grain bullets made it through the ribs--though admittedly a buffalo's ribs are pretty thick.

Have seen a number of other bullets do similar things on animals between deer and buffalo in size, which were also eventually killed, either because (luckily) one or more hunters got in more shots, or after a long tracking job. I tracked the mule deer buck mentioned in the first instance for over half a mile, eventually spotting him standing broadside, the leg obviously broken, and got in a quick shot that made it through the ribs into the lungs.

Ok then. Ta for that John. I assumed mine were the older tougher ones as they are the old clear orange boxes. But maybe not the case.

Strange things happen. Shot a 100# dressed doe in CT with a 180 gr Hornady Spire in the late '80s. Broadside shot well behind shoulder. In recoil saw a 3" hole open up as deer went down. Bullet had come apart on a rib. I have the jacket, which split lengthwise. Impact velocity could not have been above 2600 fps.

Around that time a friend had the same experience with two shots on a Newf moose using WBY .300 factory loads and that same bullet. Another friend finished the job with a .338.

Doesn't mean cup-core bullets are worthless, or that Hornady bullets are no good. Just the nature of anecdotes.

I had a similar experience with a bullet a manufacturer had just released to the public. It was a whitetail doe and with a 30-06 - the bullet never entered the rib cage. I stopped using that manufacturer's bullets and that was probably at least 30 years ago. However, I have seen that manufacturer's bullets used on deer and they work very well. (I finally stopped belly aching about those bullets.) That wasn't the only bullet failure I've seen with bullets that were released to the public - I can think of four different manufacturers' bullets that were rather poor when they came out, but were much improved later. These experiences align with what a wise gun writer advised (I'm loosely stating and at least as I recall), that newly released bullets were later improved after field failures became evident.

The first bullet I used that I thought was an complete failure was the very first Grand Slam bullets. Clearly they were improved later, I think within a year or two and then much later maybe they were changed to be made cheaper? I do not know.

I suspect that manufacturers are anxious to get their bullets out to cover the cost of the development. It seems to me to be a financial issue - return on investment. I wish that bullet testing would be more rigorous before some poor slob (me) shoots and loses his trophy (or white tail doe). Maybe it is my responsibility to test every new bullet I try before going hunting with it? It's tempting to use what has been a time proven bullet, but I can't help myself when a new whiz-bang bullet comes out and the bullet is advertised as the greatest ever.

John, thanks for your detailed explanation. I can now see where you are coming from. In my two cases with the two elk, the jacket was found right at the ribs, but the core continued to penetrate, although not in a straight line. Fortunately, follow up shots finished both elk.

test1328,

Have seen the same thing on a couple deer. In one instance the core killed the deer, pretty much instantly--but I doubt it would have on a shoulder (not rib) shot. The second time the core kept going and broke the spine, dropping the deer (which needed a finished, but they often do with a spine shot). Both were eating-size bucks, a mule deer and a whitetail, probably weighing no more than 120 pounds field-dressed.

But never did trust or use those two bullets again.

I've used the 160 gr. Grand Slam in my old 1185 Browning in 7RM to make my longest kill on a west Texas muley. 603 yards and the unluckiest deer on the ranch. The old 160's and 145's shoot less than 1 MOA in my 1885. I haven't loaded any in a long time and just recently ordered another box of the 145's and loaded them up for use at my lease for pigs and feral sheep. I wasn't aware that Speer had made some changes to the bullet. I think they changed the ogive just a little because overall measurements changed when seated to the same ogvie length. Maybe. I'm not quite sure. I've still got a box of the older 160's and I guess I'll load them up one day.

The new Grand Slams are just as accurate in my 1885 and I plan to whop a few pigs and feral sheep with them this fall.

My Browning Stainless Stalked in 270 loved the 130 Grand Slam. I've tried to order some 130's and 145's but cant' seem to find a vendor that has both weights. It seems they either have one or the other and I'd rather not pay that much in shipping.

I use 180 gn. in my 300 Wby. They are the most accurate bullet I have tried in my rifle. Every deer I have shot with them dropped dead like a light switch was turned off. They do less meat damage than the smaller stuff most people I hunt with use.
Mine are in the orange boxes. I like them.

Hogwild7,

What I am wondering is whether you're shooting deer in the shoulders, or anywhere in the chest. Am asking because another guy on the Campfire claims the same sort of "light-switch" thing when shooting Southern deer with the .257 Weatherby and 100-grain Hornadys.

Another reason I ask is that have found many hunters don't (or can't) differentiate between shot placement, cartridge and bullet.

Interesting thread, I've been using the old orange and yellow plastic boxes of Grand Slams in 120gr 25 cal, and 175gr 7mm I bought back in the late 80's, only have a few of the 7mm 175's left, they're the only bullet I've ever fired in my '09 DWM 7x57, have yet to recover one from deer or pigs, very accurate and hard hitting leaving at 2700 fps.

Just bought some of the 17 buck a box 285gr 375's from Grafs, thought I'd treat em like a 270gr Hornady and rum em an accurate 2600 or so, bet they'll hold up for all conus and any African game short of the big 4 just fine at that speed.

Yes Sir they do SOTG.

I tried some .257 120 grain grand slams once. Accuracy was not to my liking so I gave them away.

My reasoning was that the trial wasn't at all fair because I only tried them once........but the Hornady hollow point shot so well that it didn't make sense to look elsewhere.

I bought the 120gr Grand Slams because at the time I had a Ruger 77 in 25-06 with some sort of semi-heavy 24in barrel and walnut stock, those bullets over a max charge of 7828 were deer death rays ; ] never got one of those back either.