223 loads and velocities

P

pockets

New member
I started to develop a load for my Stevens in 223, using 60 vmax, varget, 205M primers,winchester brass trimmed to 1.75" full length sized. I thought it would be easier to find the best load from the ones I tried, but my results are not that definate. I tried 25, 25.5, 26, 26.5, 27, 27.2grs. 3 shot groups, and recorded velocities 12" from the muzzle. The best group was the 26gr. .553", avg. velocity of 3079 33.62ES, 17.6 SD. But the 26.5, 27 and 27.2 all had lower ES and SD, with the 27.2 having 7.58 ES and 4.12 SD, avg. of 3193 FPS, the first two shots being 1.155", and the third falling in between the first two.

The 26.5 load had the first two shots touching, the third off to the left for a 1.136" group, avg. 3126, 12.94 ES, 7.21 SD.

27 load first two shots almost touching, third off to the left and high, .734" group, avg 3176, 21.64 ES, 11.35 SD.

It was a bit windy, and I could have pulled the left shots on the 26.5, 27, and 27.2 groups. The other strange thing is the the 26 and 26.5 groups had the same point of inpact, but the 27 and 27.2 moved another inch higher and 1/2" to the left.

Should a person try the load with the lowest ES and SD again, or is it possible that the 26 grain load will group the best even though it has the greatest ES and SD? Should I load 5 rounds of each and try for groups again? I'd post pics, but am unsure how to do so.

Thanks
 
Here is some interesting reading for you:
http://www.clik.to/optimalchargeweight
I was having similar problems deciding on best loads for my guns. After readings Dan's technique I've been having much better success coming up with a load for a particular powder/bullet combo. When you read it, it might seem a bit confusing at first but it's really pretty simple once it all sinks in. I don't even run em over the chrono until I find the OCW. Once you find the load, it's very forgiving of minor variables and they all shoot consistantly. Last batch I did was 60g NBT's and Varget. Both my guns liked 26.8g with Rem 7-1/2 primers. Varget seems to like to run compressed.

peace.
unloaded
 
The potential for wind, or other deviation is one of the best reasons for using five shots instead of three....

By only using three and having one go errant, you can never be sure that you are not missing a possible excellent load in your development process..

By using five, if one goes haywire and you have four in a great group, you have a better understanding of your load potential.

The example below is one of mine where the ejected round bounced into the crook of my elbow, just at the trigger was releasing the hammer...on the fifth shot...

DTechUpper-Loada.jpg
 
I have been using an Ohler 35P since 1987 or 88, when ever they came out with it.


Couple of things you need to keep in prospective, distances you intend to shoot, and group size. 22 Caliber ES can be larger than other calibers, groups size on short range is more important.

I have an old can of AA2230 that is slow and accuracy is 1/4", but extreme spread is 120 fps. On 250 yd and less shooting, ES is a usless number with the close numbers that you are talking.

What kind of distances do you shoot?

I'm shooting N-135 with the 55's at 3550 out of a 223 bolt gun, are you sure that you are not beating your head against the wall with a 60g at a little over 3000?
 
Quote:

I'm shooting N-135 with the 55's at 3550 out of a 223 bolt gun, are you sure that you are not beating your head against the wall with a 60g at a little over 3000?



Ack that is very good .223 advice /ubbthreads/images/graemlins/grinning-smiley-003.gif
 
Here is the load I found for my Stevens 223.

Lake City Brass
CCI 400 Primers
26.7gr Varget
60gr V-Max

This is a 5 shot group, although it is only at 60 yards. This load chrono'd at about 3115fps. I let the barrel cool a few minutes between shots.

picture004ud6.jpg
 
You need to use 5 shot groups, 3 shots are just not very statistically significant. Also the chronograph should be 10-15 feet from the muzzle. At 12" you will get a lot of erroneous readings because of the muzzle blast.

Jack
 
I am planning on using it out to 300 yds. I think I will start at 26 grains, in .2 grain increments up to 27.2, and shoot some 4 shot groups. Sound good? I am using the 60 grain vmax because of it's reputation to not splash on the shoulder. I have used the 55 vmax in the past out of my swift mind you and it was not pretty on most shots.
 
Ackleyman's right, screwing around with 60's is wasting your time. I believe people shoot heavier bullets through a .223 thinking they'll get flatter shooting and better wind resistance even though they're going slower. But that's not necessarily so. Run some numbers with a ballistic program and check it out.

It's not hard to get terrific accuracy with 50's at 3600 or over in a .223, I've been doing it for years with AA2015...it's easy with VV133 too. And with VV135 my .223 gets over 3600 very accurately with 55's. Even if those 60's were doing 3200, you'd still be losing both trajectory and wind resistance to the 50 or 55gr bullets going faster. With a 200yd zero, the trajectory difference is 4" and 5" at 400yds. Zeroed at 100yds the difference is more. Doing trajectory readouts can be an eye opener.

If that 12" distance to the chrono isn't a misprint, move it out to about 10' or 12'. But if it's a misprint, nevermind.
 
ackley man and ackman, you must be quite a bit higher than Vihtavuori's listed max load with N135 to reach those speeds. They say 3337 with max load and 2 different 55gr. bullets. I have not tried going past the max load for Varget and the 60 gr vmax, even though at 27.2 grains there are no pressure signs. The case measurements and primer condition is the same with 27.2 as 26 grains. I suppose I could try going above the max, especially since the bullet is seated a fair amount longer than SAAMI specs to fit my chamber with .020" jump.
 
Pockets,
Actually, it was someone on another board getting 3600+ with vv135 and a 55gr bullet. He told ackleyman who found it was true and then told me. I don't know what the VV loading data says, but it wouldn't surprise me if our loads were over max. These loads are quite a bit over max for Sierra and the other manuals. In my rifles, vv133 is faster with 55's, but VV135 is far more accurate. With 50's, VV133 is very fast and very accurate. As mentioned, the load since early 90's has been 50TNT's at 3620 using AA2015BR powder. All bullets have a thin film of Lee Lube and are seated .005" to .010" off the lands.

About the bullet weight thing, it has to do with ballistic coefficient and velocity. Those 60's don't have a high enough BC to make up for the loss in velocity....you'd have to push them around 3500 to equal the lighter bullets going faster.

This is straying from the topic of your thread, but I suspect that when a lot of people do their load workup they stop at what the loading manual says is max. I'll put together loads up to over book max and be watching for signs of overpressure, then stop where the gun says to stop.

Manuals are very conservative.....some more conservative than others. There are people who refuse to accept anything other than what a loading manual says. To them the manual is sacred and they'll argue to their last breath about how dangerous this or that is, and how you'll blow yourself up, etc. etc. I've been there countless times with these folks, so has ackleyman. It happens whenever this subject comes up.

Assuming the barrel isn't slow, and there can be a big difference......

Brass matters.....IMI is just plain tough and primer pockets stay tight with hot loads. Lapua Match should be just as strong. I'd suspect that LC may also be strong but I've had no experience with it and really don't know.

Chambers matter.....a minimum chamber with neck that isn't Godawful sloppy, and NO freebore, will give better velocity.

Powder isn't the same from lot to lot and sometimes the difference can be substantial.

Primers even can make a difference, depending on how one works with a particular powder.

The combination of barrel and components in the manual is NEVER the same as what you're using.

Loads for the manual are tested in SAAMI chambers. None of my rifles have a SAAMI chamber.

There're a ton of reasons why the manual isn't gospel for yours or anyone else's particular gun.

This is a long (likely incomplete) explanation for why loads do what they do in mine and ackleyman's and several others' guns.
 
Pockets: pay attention to the paper and don't pay attention the the ES and SD. I have several times seen a rifle shoot lousy with low ES and SD and shoot great with high ES and SD.

To Unloaded: Thanks for the post. I really enjoyed reading the link above and the reference links provided by you link. I've been doing almost the same thing just had different reasons. Primary reason: I like to simply drop the charges without weighing each and every charge off my dillon. I've been calling these loads powder charge insensitive loads. Secondary reason: the extreme temperatures we get out here in Arizona. I always figured that if a load wasn't real critical about the powder weight it also wouldn't be fussy about other factors such as temperature, variations in powder lots and primer lots. That was really a great read.
 


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