9 hunters, 36 bulls, 8 different bullets. With all the different opinions bad advice from writers who would get fired for a bad review of an advertisers bullets and a hunter from the east who has never killed an elk or the guy who thinks you need a 375 RUM to kill an elk. A few years ago there was a shot very close to me I walked over to find a hunter with his nose glued to the ground looking for blood. He said he had shot a bull with his 300 Win mag and there was no blood. I dropped to one knee to look across the tops of the tall grass and saw a few drops of blood. A long story short after the bull was found he looked like a shotgun was used on him. I retraced the path of the bullet to find three limbs that were hit by the 180 Core Lokt. At first the hunter said it was a good clean shot. Be careful who you listen to about elk bullets and calibers. I started keeping records of a crew of 7 hunters who I hand load for. These guys all but one started as a boy along side there father and are very good elk hunters today, plus my hunting partner and myself makes 9 hunters. We have used 8 different bullets to take 36 bulls over 9 years, plus a lot of cows with leftover cow tags. All of the techs I have talked to say in 30 caliber 150 grain is the best bullet for deer and because of the thin jacket it should not be used on elk. 165 grain is suited for both elk and deer. 180 is the best choice for elk if the vel. is 2700 fps. or more. When the custom bullets were recommended by the writers a few of the guys wanted to try them. At first they seemed to do a fair job. Three years later and two bulls with not so clean kills we started to review all kills with the custom bullets. In a 30-06 with a 165 bonded bullet there was very little expansion 5/16 of an inch with 2 recovered bullets from the bulls far leg, this bull ran 200+ yards after a double lung hit. This bullet in a 308 Norma mag at higher vel. did a better job, the bullet was not recovered. In two 30-06 rifles the 165 SST is now doing a real good job with one bang flop on a bull. A solid copper bullet hit a large leg bone and lost all its pedals but one. After 7 guys and 4 hours of looking the bull was found 1/2 mile away. The 180 grain bullet from the 300 Win mag weighted only 124 grains. Most of the other elk with custom bullets averaged over three times the distance traveled till they went down when compared to standard bullets. This is still only 60 to 80 yards on average but it is clear the customs do not have as much terminal performance to stop the bulls as standard bullets. 50% less damage to organs on all bulls and less blood shock plus the exit hole is much smaller. Customs tend to pass through and take 30% or more bullet energy along with them. All the bulls shot were good well placed shots. No bang flops with any custom bullet. All hunters agreed the only custom bullet they would use was the Nosler Partition plus SST, Hot Cor, Game King and Ballistic Tip FYI none of the guys wanted to try the Ballistic Tip till I cut a 180 in half and recovered 6 bullets from wet phone books that weighed 139 to 168 grains with very nice looking mushrooms. The jacket looks just like a Accubond jacket with no bonding. The 180 Interbond at 3000 FPS. was voted second best custom after the Partition. If you must use a bonded bullet the Interbond did more damage to the engine room and left a larger exit hole plus a faster kill then the other two bonded bullets we used. At 400 yards this bullet may not open much. We are using the cow tags to try other bullets, the 190 Interlock also works very well. I cut this bullet in half the jacket is 50% thicker than most other standard bullets. It has two bang flops so far and no cow has gone past 10 yards. In one cow it smashed the leg bone made jelly out of the lungs with a two inch exit hole. Guns used were 300 WSM and 300 H&H mag. This year 168 and 185 Bergers will be used on cows. My 300 WSM will be loaded with the 190 Interlock with 63 1/2 grains of IMR 4350 at 2974 FPS. My back up gun is a 30-06 with 165 SST at 2925 FPS. The 30-06 has taken 11 bulls over 30 years of hunting. Last year I left the 300 in camp and killed a nice 6x6 with the old 06. 30-06 still kills more elk then any two other calibers put together. Standard factory ammo also kills thousands of elk each season. Four of the nine hunters worked on this article and the facts are from my records. caliber, bullet used, bullet vel. by a chrony, shot placement, distance traveled after shot, amount of damage done buy the bullet. exit hole size and bang flops. All of the elk were shot in Colorado. If you have 3000 ft. lbs. of energy put it to good use with a good bullet.