I been playing around with my .223 9 twist and 53 grain Vmax for a while now. I went shooting today and tested some new loads. I loaded a rather hot load that I SLOWELY got up too. I ended up with 26 grains of Benchmark .003 off lands. It shot like a LASER!!! It showed no signs of pressure. I shot several .5 groups at 100 yards and then I started backing up the target all the way back to 500 yards. I was using a mil/mil ffp scope. I was in disbelief on how flat it shot! I had it zeroed at 100 yards. At 200 yards it dropped .8 inches (1 click up). At 300 yards it dropped 4.7 inches (4 clicks up). At 400 yards it dropped 17.3 inches (11 clicks up). Does these numbers seem normal??? I WISH I had a chronograph!
.223 53 grain Vmax velocity and bullet drop
- Thread starter stinnett1981
- Start date
Larryh128
Silver $$ Contributor
I shoot 25 grs of Benchmark with 55 gr Ballistic tips. The velocity is 3200 out of a 20" AR barrel. I'm sure that in a bolt gun you could get to 26 grs but if it's in an AR , it's pretty stiff. My 300 yd drop is about 6" if I'm zeroed dead on at 100. This is about standard for most high velocity rounds, some of the screamers will be less but a standard 243, 25-06, 270 etc will be right in this area. Exceptions are going to be when you start pushing the 55gr at 3800-4000 (not possible in a 223) like a 22=250 AI or 223 WSSM.
Larryh128
Silver $$ Contributor
I should also add that there is a point when adding powder just makes more noise, recoil & pressure. That's where a chrono really pays dividends. Going from 25.5 grs to 26 grs might only add 15-20 fps, that's not a definite answer only a possibility. I would load & shoot about 5 cases & see if you start getting loose primer pockets after 5 rounds.
My scope is mil/mil wich is .393 inches . Im gonna go ahead and buy a chronograph. I only shot 25 at 26 grains of benchmark. Im gonna go ahead and drop the load down to 25.7 grains until I get a chronograph.
heh, Good idea on dropping loads until verifying w/ chrono. Even the books would suggest 26gr to be more of a 3200-3500 fps which does not correlate to the data given for external ballistics (3500fps would be ~8" drop at 300y with 100y zero).
Overpressure loads that don't show pressure signs through the primer usually mean other things are going on. The big data point we'd need to know more is what COL are you loading to? All of our data is based on book COL which should be near 2.250. If you are seating farther out, then I would say you have a much better load. More room for more powder and lower pressure. In that case a Chrono would verify your velocity, but it might be harder to determine MAP without something like QuickLoad.
FYI Lyman 49th Manual: 52gr Sierra HPBT at 25.7gr Benchmark is 3251fps, and only 49,400psi which is NOT max for SAMMI spec but close.
What is your COL with this load?
-Mac
Overpressure loads that don't show pressure signs through the primer usually mean other things are going on. The big data point we'd need to know more is what COL are you loading to? All of our data is based on book COL which should be near 2.250. If you are seating farther out, then I would say you have a much better load. More room for more powder and lower pressure. In that case a Chrono would verify your velocity, but it might be harder to determine MAP without something like QuickLoad.
FYI Lyman 49th Manual: 52gr Sierra HPBT at 25.7gr Benchmark is 3251fps, and only 49,400psi which is NOT max for SAMMI spec but close.
What is your COL with this load?
-Mac
2.333
The 53g Vmax is a unique bullet. Its very long for its weight and has a high BC of .29
The 53g Vmax is a unique bullet. Its very long for its weight and has a high BC of .29
Larryh128
Silver $$ Contributor
Just a thought for you, you don't need a $500 chrono. I have a shooting Chrony that has been going strong for about 20 years, no issues. If the manual says that I should be getting ----fps, that's what I'm getting or so close that it isn't funny. I do one thing different than some others in that I always set my chrono up at 20 ft from the muzzle. This totally eliminates any false readings from muzzle blast. The only thing that you need to remember is that the aiming point is about 8" above the unit(bullet is going to be about 4" low at that range). It needs to be lined up side to side & vertically as well so it takes a few walks back & forth adjusting the tripod.
2.333" COL is a bit long for the loading manual pressure ratings. This isn't a bad thing, but might explain the 26gr without pressure issues. I don't see VMAX 53gr as tested, so to determine someone with QuickLoad should chime in.
What this means is if you stay at 26gr, DONT load to 2.250" and I have a PACT chrono that is very old, and still accurate. I bought the parts off of e-bay, new sensors from PACT, and built my own stand from a tripod and carefully measured 24" spacer.
Magnetospeed is an interesting alternative, it makes for easier set-up to shoot at multiple targets without moving the chrono.
-Mac
What this means is if you stay at 26gr, DONT load to 2.250" and I have a PACT chrono that is very old, and still accurate. I bought the parts off of e-bay, new sensors from PACT, and built my own stand from a tripod and carefully measured 24" spacer.
Magnetospeed is an interesting alternative, it makes for easier set-up to shoot at multiple targets without moving the chrono.
-Mac
When I say 2.333, that means from end to end. Not base to O give. Im talking base to tip of bullet. I forgot what it measured out base to O give. Either way I know its .003 off the lands. The rifle has a somewhat deep throat. Its a Rem 700 with 26" barrel.
stinnett1981 said:
End to end is what is in the loading manual, and as you mentioned the VMAX is NOT the 52gr or 53gr Sierra MK, which is completely different in length. A QuickLoad user has fast access to the database that can determine the depth difference between the bullets. The idea being, what is the difference in case volume when a 52gr SMK is loaded to 2.250, vs a 53gr VMAX loaded to 2.333. My initial guess is that we'll find the case volume of the VMax load to be slightly greater than that with the SMK. My loading manual has SMK for the pressure reference, meaning pressure at that case volume. Bigger case volume means lower pressure. Try seating a 77gr SMK in .223 to 2.260 and you'll see what I mean, the long bullet really takes up a lot of volume.
-Mac
In my rifles the pressure changes quickly with small increases of Benchmark when at the upper limit. With 25.0 grains of Benchmark and a 50 grain Nosler BT I'm getting about 3250 out of a 22 inch barrel, 12" twist. This load shoots sub .5 moa in my Browning X Bolt Stalker. I can't seem to go above this limit without incurring pressure signs - besides with the way this load shoots there is no need to go higher for me.
Not quite a year ago I tested the BC of this bullet and found in my 3 223’s it was averaging a G1 of .271 out to 605 yards. This was verified by shooting over a chronograph and plotting impacts at 405, 500 and 605 yards, then double checking drops and a measured 100y against what I dialed into the scope. My muzzle velocity was between 2900 and 3100 for the three rifles. Not quite as high of a BC as I had hoped for but still a good little bullet... 8)
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