223 68-69gr ballistics

[gotigers]

I have been 3 gunning for almost a year now and have been shooting ARs for about 3 years. I have used mostly Wally world Federal bulk for plinking and Federal XM193 for competition. So far they have performed well enough. Recently, i have been doing some 200 thru 450 yard shooting. The XM193 is fairly predictable, but the groups are just not great and in 3 gun the 55gr is just not doing a great job of knocking down the re-settable poppers at distance.

With the longer distance i am wanting to go to a heavier SMK bullet. My current 3 gun rifle is a DPMS MK12 18" 1:8 barrel, 5.56x45 chamber. I am going to start with either 68 gr or 69 gr SMK. I have been looking for 2 days for ballistic info. Maybe my google-foo is weak, but do any of you have any ballistic info on the 68-69gr SMK or a link to such info?

Thanks

 

[Mags]

God forbid you check a loading manual.

http://data.hodgdon.com/cartridge_load.asp

Select Rifle, then 223, hit enter, then select 69 grain. Voila!

 

[Cemetery21]

Plug in your data and it should give you a chart you can compare for trajectory, energy, etc.

http://www.handloads.com/calc/index.html

 

[MtnCreek]

A match 68 / 69 gr bullet will probably give you pretty close to the same bullet drop as the M193, even at lower velocities because of the better bullet design (higher BC) and will be more accurate.

 

[TonyAngel]

If you're running a 1:8 twist barrel you may want to look into the 77gr projectiles. I mean, why not? They'll have a bit more thump and will likely shoot as well as or better than the 69s.

I was running 24gr of either Varget or Reloader 15 with the 77gr SMKs in my 18" build with a rifle length gas and it shot very smoothly.

 

[Z-Michigan]

I agree with Tony - you have the twist rate to use 75/77gr bullets, which have the highest BC of anything you can load into an AR magazine and are widely used for competition. Just another option.