Home Forums Hunting & Shooting Ask The Gunwriters 123SST vs 129SST

Just noticed that Hornady makes both of these bullets in 6.5MM. The application for both is "Medium Game". Anyone have any intel on why they would make two similar bullets so close in weight? Thinking about a bullet for the 6.5 Man Bun. Thanks.

If you check, you’ll see also, that Sierra now makes a 62 grain.224 SGK as well as the 65 grain. If I understand correctly, it was done in response to the popularity of the 65, to provide essentially the same bullet in a design that didn’t require as fast a twist to stabilize. Maybe that’s the case with the two Hornady offerings.

I would assume the 123gr bullet is better suited for 6.5 Grendel speeds, whereas the 129s are more likely intended for 6.5 CM/.260 Rem and 6.5x55 Swedish velocities.

Jason280 is correct. The 123 grain version was designed with the Grendel in mind.

I've used the 123 grain SST quite a bit in Contenders and at muzzle speeds ranging from just over 2500 fps to a tad over 2600 fps. They've killed very well on the hogs I have shot, but they are not exactly predictable in performance. They've fully penetrated and exited on quartering shots on 200+ pound hogs but failed to exit on a 50 pound shoat and an 80 pound sow (broadside shots on both of those).

Most of the time, they'll break up a bit and shed their cores, creating quite a devastating wound channel.










In the photo below, the bullet on the left penetrated the shield and shoulder on entry. Only the jacket was found. The bullet on the right entered through ribs, penetrated the offside shoulder/shield and lodged just under the hide. These two produced identical results in terms of quickly dropping two large boars, but they ended up looking quite differently.

Thank you, Gentlemen. Looks like you are dead right. Upon further investigation of the Hornady website, I see that the 123SST is listed with the Grendel/LBC/Lapua.

Is that a 6.5 Bullberry? I have a .25 Bullberry in a 14" barrel, still haven't done much with it other than forming brass.

I have a 24" 6.5 Bullberry and a 24" 6.5 BRM. I just can't seem to get away from the 6.5 bore diameter. Back when I was still mobile and could get out and hunt, I used a 26", 1:8 6.5 BB Imp and killed dozens upon dozens of hogs with that one. I had it long-throated and used N160 with everything from 120 to 140 grain bullets. It afforded more velocity than any other powder back then.

AA2495 and Varget (SW Precision) are what I use most in my current barrels. Re-15 did very well, but it became almost impossible to find, so I switched to what was available.

You'll love that 25 BB.

Here's a hog taken with the 6.5 BB and the 123 grain SST.







The BRM is wicked on coyotes, too ha ha.










Here's 6.5 BB brass made from .375 Win cases. Doing so eliminates fireforming.