.223 case capacity.

S

Shegs

Guest
I've only been using a centrefire for about six months and having loaded 23.0 grains of H322 with 55 gr V-max heads I'm getting 3/4" at 100 yards, but the velocity spread is large (100 f/s) and I can't figure out why. Also I have just got some Varget to try but when I get to 27-27.5gr max load there isn't enough space in the case without compressing the powder 4-5mm when I seat the bullet head (same 55gr V-max as I'm using with the H322). Is this compression of the powder safe, and will it lead to unsafe high pressures.
By the way the rifle I'm using is a CZ527 hunter with a Wildcat Predator 8 moderator.
 
I have used Varget in the .223 with the longer Sierra 69 MatchKing and experienced the powder "crunching" or compression you are talking about. Seems to be common with Varget from what I have heard.
 
100 fps with your combo is not uncommon.....

You did not state what kind of primer you are using nor the seating depth.

I used a 7 1/2 with 23.5g, also seated the bullet to touch the lands which lowered the SD, accuracy was excellent.
 
CCI 400 primer, bullet seated 0.020" off the rifling, COL 2.268".
 
.223 loads

Your loads appear a bit hot. I use 25grs of varget with 69 gr sierra's and the same with 52 gr heads


pwiz
 
I was just using the recommended loads on the Hodgdon Varget tub. Having said that, they quote winchester brass, whereas I am using Remington brass, so maybe there is a variation in the relative case capacities.
 
try vitv n133, I use 25.2grs with coated bullets, start low and work up, also lapua brass, more $$ BUT, well worth it!!!!,fed 205 GM or rem 7 1/2,

the wind is my friend,,,,,,,,

DD
 
With 55 gr bullets in a bolt gun I think that H322, N133 and powders that fast are a little too fast. I used to use 25.5-26.0 gr N135 with 52/53 gr bullets, and think that N135, N140, H4895, or Varget would work well with 55's. With the last three powders I'd start at 24.5 gr and go up to where you're getting the pressures/velocities you want.

RP cases are heavier (less case capacity) and softer than Winchester or Lapua cases.

Try various primers to see which produces the best accuracy with the powder that looks best, but back off at least a grain in powder charge when you change powders.

I used to shoot in a factory BR class where most of the shooters used .223's with 52/53 gr bullets, which is a good compromise between velocity and accuracy out to 300 yards. In good conditions, the better shooters could shoot 1/2 MOA ten shot groups at 300 yards, occasionally smaller.
 
Finally got round to using the 27-27.5 grain loads (compressed), no signs of excessive pressure and the velocity spread went right down to 9 fps min with an average of 18 fps, I'm pretty happy with that, so it looks like a full case has done the trick. I'll have to see how much I can up the H322 load to fill the case, without compromising the pressure limits. This should reduce the velocity spread and improve the repeatable accuracy. Mind you, I whacked a rabbit at 247 yards a couple of weeks ago, so it's going where I point it.
 
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