6x45 vs .223?

[mikgarus]

Is it worth building a 6x45 vs a fast twist .223 rem? This for medium distance target shooting [500 yrds & less]

[darkker]

Just depends on what you use, and want.
223 - 77gr SMK or a 75gr Vmax in the 6mm. Both using hodgdy launch speed, and 500 yard max. 900 ele. 59 deg, with 30% RH and 10 mph side wind.

223
Drop - 3.5 mils
Drift - 1.5 mils

6mm
Drop - 3.5 mils
Drift - 1.7 mils


The increased diameter of the 6mm means you need to go much heavier in order to get the length needed for a similar BC. Speeds are a push given the same parent cartridge.
The practical difference is that the splash with the 6mm will be easier to see.

[Hotolds442]

Yes. In some states it allows you to meet the minimum caliber requirements on certain game.

[mikgarus]

I was thinking of the SGK 85 gr & the Hornady 87 gr Vmax

[squirrel_slayer]

for 500 and in I'd say a fast twist .223ai would take the nod. reason being for the ai is mostly for not having to trim your brass and a small boost in velocity. I would also have it throated for the 75 or 80gr eld-m (since the amax has been discontinued)

if you think you may want to stretch past the 600yd mark in time then the 6x45 may be worth persuing "if" you get it throated for the heavies (ie the 90-105's)

both of them are a waste of potential with standard throating in a bolt gun in my opinion. why restrict yourself to 2.26 coal when you have room for more? your shorting yourself out on the ability to shoot the higher bc bullets and robbing velocity since the bullet is taking up powder space.

[Deadshot2]

Yes. In some states it allows you to meet the minimum caliber requirements on certain game.

Not to mention that the larger diameter bullet will allow you to snag an extra point or "X" in a Match.
When score shooting and faced with the choice or two calibers having same ballistic characteristics, go with the larger diameter.

[taylorce1]

Yes. In some states it allows you to meet the minimum caliber requirements on certain game.

That's why I'm building a 6X45 with a 1:7 twist, CO doesn't allow anything smaller than 6mm/.243 caliber cartridges. If simply wanting to shoot targets I'd probably build a fast twist .223, though build either to use the heaviest bullets for caliber possible. I'd twist for using 80+ grains in the .224 and 105+ in the 6mm even if you never use them you do have options if you change your mind later.

In hunting situations I really don't care about trajectory too much I have my drops down, I worry more about wind. With the 105 grain bullets in the 6mm you don't have to compensate as much for the wind even though they'll start out 300 fps slower than the 87 grain bullets. Not to mention at 500 yards the speed of the 85 and 105 grain bullets is essentially the same. Plus the heavier bullet retains more energy down range if using it for hunting, more energy should relate to more expansion which leads to larger wound channels. I don't think energy is has a direct correlation to killing efficiency, but more is never a bad thing. I do believe that regardless of bullet weight the bullet with the fastest RPM expands more violently, which IMO is important when using mono metal bullets for hunting.

I've purchased slower twist barrels before like when I built my 6-222 Rem Mag aka 6X47 Rem I used a 1:12, if I could go back and do it again it would have at least a 1:8 twist. I see no downside to having a barrel twisted faster than I need, but I can't say the same about a slow twist barrel it just limits options. The only reason I don't change the barrel is it shoots 70 grain Nosler BT and Sierra Varminters into itty bitty groups, plus the 70 NBT has been tough enough to take down deer and pronghorn for me out to 300+ yards.

[handirifle]

The only negative to super fast twist, is the very light for caliber bullets MIGHT come apart at high velocity. Not sure the 223 can do it though, might take more speed than it is capable of.