6mm or 243AI?

[Varmint Hunter]

[ 04-07-2004: Message edited by: Varmint Hunter ]

[Varmint Hunter]

If you are interested, here is an easy to use ballistic calculator that can help you make comparisons.

VH

Ballistic Calculator

Partagas:
I may have said it before, but I will say it again. The 6mm Remington is probably the most overlooked cartridge on the planet. I load 41.2 grains of “Varget” behind an 80 grain “Nosler” ballistic tip bullet. That charge sends it downrange, out of a 26 inch "SS Shilen" barrel (1:8" twist)at 3386 fps. It makes .176" groups at 100 yards and performs exceptionally well downrange. The 6mm AI may be popular, even trendy; and the .243 tried and proven, but so is the 6mm Remington. It is my favorite varmint cartridge.

[ 04-07-2004: Message edited by: W ]

[Partagas]

Will a twist that is fast enough to stablize the bigger bullets such as 90+ do ok for the 55-60 grainers? From what I have read (I am still learning) the twists that handle the bigger bullets handle the lighter ones better than the other way around.

[Jake in NC]

Varmint Hunter..
.. According to Point Blank Ballistic Calculator there's about a 16" disparity between the 55grBT and a 107grMK at 750 and about a 5" difference at 500 for windage.. Where are your calculations that show the lower BC'd bullet having better wind deflection resistance coming from.?? I was suprised to see how well the 55gr bullet maintained tragectory but I can fairly well predict trajectory and allow for it by clicking it in.. Wind, OTOH, is a different thing.. What's your priority.??
..I bet that little 55gr pill @ 4K+ is pure hell under 500.. Hehehe.. I run the 75gr VMAx's myself and have been very pleased with their performance.. Thanks.. d:^) JiNC

[Varmint Hunter]

Jake,

As I said in my previous post, by heavies I was refering to 70-80gr bullets and not to the 105-107 VLD bullets. My 12" twist was never intended to use them, as I preferred to use traditional "varmint" bullets. The VLD's always have an advantage with the wind due to their exceptionally high BC.

But to put some numbers on the comparison, here is what I got using moderately high velocity (but not max capable in the AI's)and calculated with a 10mph cross wind.

55gr B-Tip @4,000.....63" @750yds
80gr Sierra @ 3,300...67" @750yds
70gr B-Tip @ 3,600....61" @750yds

The little screamer 55gr B-Tip is very destructive on groundhogs and is as good or better than some others in the wind. It can also be shot quite a bit faster in many 6mmAI rifles but I tried to keep the comparison fair.

As for your Sierra 107's, I'm not sure what kind of terminal performance you get from these bullets but they sure do buck the wind. In my comparison the difference was not 16" @ 750yds, but 20". [img]images/icons/shocked.gif[/img]

Good shootin' - VH