I have used both of these but in vastly different calibers(165/30-06 BT & 117/25-06 GK) for deer with no complaints. In the lighter caliber is there any practical difference between the 2?

Used the GK 117's in my 25-06 and took a few white tails with it. Accuracy wasn't too bad, around an inch. Got a few 120 BT's in a trade and got 3/4" groups and put a couple of deer down with them. Both will work fine for pretty much anything you're planning on shooting with the 25's. Now the BT's are just for fun as I've switched to the Accubonds as I'm getting .5" groups with them and they work real nice on the deer.
I still use GK's in my 308 and 30-06 but playing around with some 150 AB's in the 308 for elk.

No...

Todd

The deer won't be able to tell the difference, so use the one that shoots best in your rifle.

I use them both, one is as good as the other.

I find the GK to be softer than current gen BTs, but both kill whitetail just fine. If you push the GK fast, it will not exit sometimes. OTOH the BT tends to exit for me. Makes sense as the BT has a heck of a lot thicker jacket in comparison.

I've only shot the game kings and silver ballistic tips in a 25-06. If that were my only two options, I would only bow hunt. I couldn't stand the performance of either of them in the 25-06.

So you like them to run a bit?

I've run Gamekings in 243 and 257 Bob and Nosler Solid Base in the Bob to exact same effect on all deer/antelope shot. No exit on mostly broadside and slightly quartering shots, ranges 25 to 200yds, animals made it a maximum of 30 feet. Quite effective, no drama. Those were my first five years of big game hunting.

Cant blame you...those are both [bleep] bullets.

Any decent bullet is 10 times better than a sharp stick!!!!

I've had pretty good luck with both over the decades, taking 9 different species of big game. Prefer the heavy-jacket Ballistic Tips for game larger than deer, and have taken several animals in the 500-pound range with them, including two bull gemsbok and my largest-bodied caribou. But have good luck with both Sierras and smaller Ballistic Tips on deer-sized game in both North America and Africa.

You are correct

I've used the 120 BT in a 260, and the 140 GK in a 6.5 CM both at modest velocity. I've yet to recover one from a deer and most of my shots are 30-150 yards. Accuracy for both has been excellent.

Have used the 100 gr GK in the Roberts for 30-40 whitetails. No complaints here.
GreggH

I've killed a lot of deer with Sierra bullets over the years without complaint, mostly out of a .270 with the 130 Pro Hunter. Currently I use the B.T. a lot because it is one hell of a deer killer. However, if I'm ever forced to use just one style of bullet it will always be Nosler's Partition.

Saw the strangest "die" ever with a BT.
I've been taking 6-10 deer a year for 35 years, so I've seen some strange things.
I shot this buck at about 40 yards, chasing a doe.
Hit him square in the neck with a 125 BT at a MV about 2200 from a Ruger 300BLK.
At impact he laid down then fell over dead.
Just laid down like he was going to nap. Then dropped his head to the side and fell over.
Crazy.
No exit. Bullet was under the hide on theoffside.