That's what I figured. I kinda wanted to check the tightness of the mount screws into the receiver but the top ring halves are torqued and/or loktited so hard I don't want to risk messing them up, I'm going to guess (hope) the base screws are in securely as well. The 5 shot group I shot looks like probably the optics system is secure.
This a loaded issue from the point of view of ethics which I'm not really qualified to comment on from an informed point of view. From what I understand, getting any part of the animal out of the country is extremely difficult so hunters typically donate the meat to locals. My friend is aware of the illicit ivory trade and trafficking of tusks--and is the reason he refuses to take elephants. Trophy hunting isn't for me personally and I won't kill anything that I don't intend to eat, but done responsibly, legally and in controlled guided circumstances that benefit the locals--I'm not going to judge it.
First thing I would look at is jacket material on those big bullets. You might try copper solvent followed by a light pass with JB Bore Paste or steel wool to take some rough spots out, then Militec the bore. I Militec the bores on all my rifles, makes them slick slick slick. Heat in an oven, apply Militec-1 oil to a CLEAN bore, bake for 1 hour. Leaves a dry lube behind for several hundred rounds IME.
I've gotten the bore clean (I too have millitec) and the real issue is why it's happening. After finally getting through all the "layered cake" I discovered mild pitting down the rifling for a large part of the barrel's length, almost certainly the cause of the copper fouling. I had a conversation with the folks at Weatherby and we came to the conclusion that more than likely moisture was attracted to the carbon build up over time (years) and started incipient rust/corrosion. There's lots of hunters out there who believe they should never clean their bores as long as they are getting accuracy out of their rifle. I'm not one of them. My friend and I both live in Maine, which is itself a very hard environment on anything--the moment you drive a new car or truck off the lot it starts dissolving.
I shoot 300 wby's both with and without the Accubrake, I don't notice all that much difference in recoil reduction--maybe on the order of 20% or so--but there most definitely is a benefit in reduction in the propensity for muzzle jump IMO--that is without a doubt a great thing to have if you need a quick follow-up. It might be the more powerful .416 gets greater reduction in felt recoil, my honest opinion is the rifle as equipped from Weatherby hits about as hard as a stout 45-70 but is more controllable. I don't think additional padding is necessary, those guys at Weatherby designed a perfect big/dangerous game rifle IMO.
Yep. Monolithic solids can do some wicked fouling very fast. I shot some Federal Premium jacketed Tungsten solids in a 416 Rigby and it took me weeks of soaking to get whatever that particular alloy CU jacket material out.
Most of the big, slow rifles shoot better moderately CU fouled than clean.
I am talking about wrapping your fingers around the barrel on your foreend grip and squeezing tight.It's not that slow--even the bigger bullets are going around 2700 fps. The problem with "let it foul" is allowing a build-up to trap potential rust /corrosion action by attracting moisture over time--which is exactly what I think happened to this rifle. It can also be hard to tell just how much build-up there is; I've cleaned barrels many times and was fooled by the color of the bore when I thought the job was done, only to break through to a new layer of shiny copper.
Holding tight and pulling in fairly hard is a matter of self-preservation with the bigger recoiling cartridges in my experience, you're probably going to get hurt if you don't. This Weatherby Mark 5 is very well made and balanced IMO, around 9 pounds weight with meat in the right places to get a really good hold and shoot steady. Keeping the recoil impact from getting a "running start" is key to making the felt recoil very tolerable IMO--along with the Accubrake which I'm sure helps helps reduce muzzle jump as well. I genuinely enjoy shooting this rifle, making big holes with big bullets going fast is kinda fun (though expensive).
I believe every rifle is different, some foul up worse than others, some tolerate fouling more than others etc. This is literally a one shot, one kill rifle--or else the shooter himself may possibly end up the prey. I don't know how else to treat this other than the first cold bore shot must be as close to perfect as possible. I'm confident right now that I could hit the POA within an inch or so with the rifle cold, maybe even right on the POA. A foreend grip all the way around the barrel sounds a bit extreme to me and unnecessary with this particular rifle, I suspect an adrenaline-fueled death grip could very well cause a barrel pressure point distorting the bullet's path through and out the bore. Not saying you're wrong, just what I've observed shooting this particular rifle.
I had your exact same thoughts about accuracy/pressure. Dangerous game rifles have their own set of rules. Accuracy is not nearly as vital in them as it is in other rifles. The vital areas are huge. How accurate were the old Holland and Holland doubles that killed countless thousands of the original big 3? I used to work for a man who killed 4 elephants, 3 lions, countless cape Buffalo. 1 or 2 Rinos. His 375 H&H double would shoot 4" at 100. 458 Win was about a 3" at 100 rifle. 416 Rigby was around 4". 460 Wby would shoot 1.5" but he never took it to Africa.