I’ve commented on the other threads about this but will add here as well. We shoot crop damage. Basically now til October taking out deer in farm fields through DNR. We have A LOT of experience with caliber/bullet on whitetail deer. My personal uses and opinions are,
223/556- Have killed a decent handful of deer many years ago. Mainly head shots. Worked excellent for that application. Most kills inside 200 yards
6.5CM- Honestly left much to be desired. Using 143 ELDX. We run the same bullets in the 260’s. Some impressive blood trails but mainly a lot of what the op experienced. Deer that would run and be hard to track. I also shot many deer with the SMK in the 260 longest being 1,121 yards. Similar maybe slightly worse results than the 143 ELDX. Most kills 100-500 yards. Several over 600 yards.
308- This is our main round. We run about 8 rifles chambered in 308. All using the 178 ELDX, 165 sst or 150sst. Have also used some Sierra game kings as well as match kings. All killed deer but the smk would rank worse for me. Either it left little to no blood or blew apart and usually resulted in lots of damage. The Game kings did what they’re designed to do. I’d rank them with the performance of a Rem corelok bullet. The 178 ELDX have been absolutely awesome. They don’t seem to be picky on speed. If the deer doesn’t drop it usually leaves a blood trail you can sprint down to find the deer. Most kills 100-500 yards. Longest being over 800 with a decent amount over 600.
300 WM- Run a couple of these. My personal favorite is 200 ELDX bullets. These bullets just plain kill shit. I have a Tikka T3X running 178 ELDX that did great on a couple 8 pt bucks in November last year. But not much experience beyond that with the tikka. This gun mostly saw fields shooting 300-700 yards. Where it performed excellent
338 Lapua- Ran 300 grain SMK bullets. Very mixed results. Most kills were 300-700 yards. Longest was right at 1,000 yards. Some pin hole in pin hole out. Some would take half the shoulder out. Just depends what the bullet hit
Keep in mind the SMK are not designed for deer, we no longer use them and based on my results would not recommend them in anything
The ELDX in 178 and 200 grain have been the most consistent. The performance doesn’t seem to be as effected by speed based on my results. I’ll be running 212 ELDX in a 300 PRC soon pending they shoot well
The SST and Sierra game kings performed great. But rarely do we shoot over 200 with those. Mostly used in cheaper platforms that go out in inclement weather or in the AR10’s.
I have yet to see a 6.5 round impress me enough inside 700 yards vs a 30 cal variant to make a switch. I do prefer the 6.5/260 for targets. Especially over 800+ yards. I think it shines there.
Just my experience in last 15 years of crop damage with 34 kills over 600 yards (two over 1,000) on what I’ve seen performance wise. I would select 308 before 6.5 and 300 before 308 if I want the extra distance. Shooting AR10’s from RR and Armalite and bolt guns ranging from Ruger American and savage 10’s to several AI platforms
But I do bench 300, worked in a bit of concrete a few weeks ago and have something like 8-10 bow kills. So take my advice for what it’s worth