Decided to get the 30-30 out this year for some whitetail hunting. Been awhile since I've killed a deer with my 336 and I was using 170 grain Core-Lokts. Do y'all feel the 150 grain bullet is more effective on deer than the 170? Figured I might get better expansion with the 150gr...

I tend to prefer the heavier for caliber bullets. IME they are very effective. The expansion question will vary by bullet, brand, distance, etc.

I prefer the 170 gr bullets. I doubt you could by a bad 170 gr bullet by any american ammo manufacturer.

Doc

I've been hunting with 170 grain Power Points by Winchester for many years. No disappointments with lethality or penetration performance.

Sherwood

That's good to know, picked up a box of 170gr Power Points last week at Walmart for $14.00.

You are good to go!

I like the 150's better for deer but use the 170's most often because of bear and deer season together.

They both work just fine.No bad choice here.

Agree with Huntz. Deer will never know the difference. I shoot 170's, but shoot whatever shoots best.

I've been a little disappointed with the penetration of the 150 gr. WW Power Points. I think the 170gr. bullets make a better choice, and are certainly what I'll use next time.

Granted, the 150s killed, but I like TWO holes leaking.

I have to agree with ratsmacker. If all else is the same, the heavier 170 will penetrate better. Easier to stop a truck than a train...

More important would be shot placement. Both rounds would do well out to 200 yards or more, if the shot is placed well. So, whichever one shoots better for you and your gun would be better than weight. Afterall, you can't kill'em if you can't hit'em.

The 150 power points don't penetrate well and often don't exit deer. If you want to shoot that weight the 150 core lokts penetrate better. I have put them through both shoulders on good sized bucks with exits more than once. The 170 sp's from Remington, Federal and Winchester are tough to keep in a deer with anything but lengthwise shots and all kill well.

I have only two samples of 150 grain bullet performance on Whitetails and no 170 grain samples because my 336C prefers the 150 grain bullets of Remington, Winchester, Federal and especially Hornady Whitetail.

2015 buck was shot at 75 yards with complete pass thru and died inches from it's bed. 2016 buck was shot at 60 yards with complete pass thru and death run was 30 paces.