I cannot believe I read the whole thread while already knowing the answer in the definitive. I have been a 6mm fan for years and have made a few longish range shots with the 243AI and 115 DTacs. One of my favorite hunting memories was killing a antelope at 540 and watching the land owners jaw drop. I have smushed a couple MS whitetail bucks between 500 and 600 yards. I have killed a pile of whitetail does from 20 to 500 yards.
A couple years back my youngest nephew, 14 at the time came to me and told me he wanted to build his own rifle. I have had him training on the mill and the lathe for a good while and knew he was pretty close to being ready. So, I scrounged around in the parts bin and found a short 700 a 9 twist 6mm barrel in a no.2 contour, think it was a lilja, may have been a schillen. I saw a cool looking mountain rifle stock on the classifieds and ordered him an olive drab 2.5-10x40 luepy with cds.
I directed him how to true the action using the PTG bushing method, I did not think he was quite ready to single point threads. I gave him the measurements I wanted the barrel shank to be, then I cut the threads on the lathe. He ran the reamer in and cut the crown. I showed him ho to pillar bed the stock and he was proud of his job.
He was also proud of the finished rifle, after he ceracoated the barreled action and adjusted the factory trigger.
I cut him loose in the reloading room. He knows how to use quickload, knows how to reload, and he is a good shooter. I have seen him hit 100 out of 100 on a 16 inch piece of steel at 800 yards when fireforming cases for me. But, it was his first time working up a load. He came up with a 95gr TSX load that only had about 1/3 MOA of verticle at 600 yards.
So he took to hunting with the gun he built and with the rounds he loaded. He passed a lot of young bucks and took a few does with it. Season was almost over before he found a shooter buck. A 7 year old buck that we had named moses because he seemed to wander the wilderness, according to the far spaced game cam pictures ambled through a road he could see 190 yards from his stand during a drizzling rain in january.
I was hunting about 3/4 of a mile away and heard the shot. A few moments later the text messages start rolling in. He has already figured out which deer he was shooting at and was excited. I told him to stay put then headed out to help him.
When I pulled up on the buggy he was standing on the road into the stand. He had found a spot of blood. So I let him finish the job of tracking. It was short, only about 30 yards.
Here is a pic of Tanner, the gun he built, and the buck he killed, moses. I only wish I that someone had been there to let me get in the pic with him.
Here is a pic of Moses ribs after tanner tenderized them with a 95 TSX.
Sans a bullet proof vest with some hefty trauma plates, there is not a deer alive that could run very far holding that bullet. Tanner enjoyed building his rifle so much he helped me put together a couple more 243AIs recently.
Anyone who says a 243 is not enough gun for deer has no idea what they are talking about.