Ladder building question

[COLT45SA]

This is about a Ruger 77Mk II in .223 with a 1:12 twist barrel~!
I'm starting to find a new load combination for this rifle and I've picked a powder to try, in this case N133. Do I load several of my first trial bullets and start with 10% less than the starting load recommended by the loading manual followed by incremental increases of 2 gr for the next batch of cartridges? Is that enough to decide if that's the best powder or should repeat that sequence with another bullet wt and manufacturer?
My dilemma is which do I look for first, the powder or the bullet?
I've followed numerous discussions on this forum and am trying to find the most accurate load combination and picked my starting powder based on a consensus I've found. And yes I do know that every rifle has its own likes and dislines.

 

[KMW 1954]

Normally I start with a dummy loaded case to find the bullet touch length. Then back it up .020" for the jump. From there select the powder which in this case is N133. Find the selected bullet or bullet weight and start at the suggested start load. From there I load in .3gr increments up to max. Because I am loading at near max length the max pressure and speed is usually lower than published.

I make three samples of each and shoot them in round robin order to evaluate groups. From here I look for two loads that look alike. That then gives a spread of .6gr which will usually prove a node.

Another shooter I know does this same thing only in .2gr increments.

 

[RegionRat]

Bullet or weight is typically your first selection, followed by the powders that work well in the weight range.

Care to share what bullet or weight you like? What or how will you use it?

ETA: Also, is this a factory barrel/chamber. or a custom or aftermarket barrel?

 

[COLT45SA]

Bullet or weight is typically your first selection, followed by the powders that work well in the weight range.

Care to share what bullet or weight you like? What or how will you use it?

ETA: Also, is this a factory barrel/chamber. or a custom or aftermarket barrel?

Consensus seems to be 52 gr. I have Sierra 52 gr Matchkings, Nosler 52 gr Target Match, Hornady ELD Match, and Hornady 52 r Match HPBT so far, but may try some other brands. Any recommendations~?

 

[wildcatter]

I find most rifles in smaller caliber like it close to or in the rifleing. When I'm starting load development I never start jumping bullets.

I start .010" to .015" usually .015" into the lands. This does two things for me, I find my top preasure, and possible my best seating depth. But after that, I start backing off the rifling, coming out .003" at a time.

Since usually all.my smokeless accuracy loads end up being near the top, I use that load to start a seating depth test.

By starting here, after finding the top end as I test seating depth backing out pressure drops. If I started off the riflings. Then started going in, pressure would rise.

Out of dozens of barrels under 25 cal. I have only found one that grouped better off the lands, a 222 Remington about 006" off. The rest are usually from touch, to .008" in the lands. Once I find that best depth then I again work up and down .2ths of a grain at a time to to confirm charge.

But as far as bullets, anytime you change, expect pressure to as well depending on the bullet.

I use 3 shot groups looking for best results, and 5 shot groups to confirm. I also in a Varmint, or Hunting rifle, shoot that group, with about 5 minutes between shots after my confirmation group. This assures me that with a cold barrel, that shot that counts most, the first, finds its mark.

Just up to you how critical to be, and what you want the load to do. JTWIDI

 

[CharlieNC]

You have a reasonable plan. Focus on changes in vertical poi on the target to identify the zone where it is stable, and the group sizes will follow with respect to charge weight.

 

[RegionRat]

Consensus seems to be 52 gr. I have Sierra 52 gr Matchkings, Nosler 52 gr Target Match, Hornady ELD Match, and Hornady 52 r Match HPBT so far, but may try some other brands. Any recommendations~?

You seem to have the bases covered for short distance target work.
Is this barrel the original factory barrel or has it been changed?

In any case, here is the N133 data from VV's web site showing their recommended start and max charges.
Their data represents a 25" test barrel so adjust expectations for your own barrel length accordingly.

Their spread is from 22.5 to 25.0 grains. N133 is easy to handle with no issues in 223 for your bullet choices. It is in very common use for 223 loads in Europe and very popular here in the BR circles.

Here is the Sierra data from the main web site. As you can see they are roughly the same from 24" barrel.

Do I load several of my first trial bullets and start with 10% less than the starting load recommended by the loading manual followed by incremental increases of 2 gr for the next batch of cartridges?

If you are willing to burn the effort, try the ANDT method that has been written up on several forums and posts by "Molon". It does require you to analyze your target results and to burn at least 5 shots per powder step, etc. , but it does tend to have it over with in terms of evaluating a given bullet/powder combination. (You will have to focus while shooting that many "good" shots in order for the answers to be honest.)

Because so many folks have run these combinations, I am going to suggest you run your powder steps to include the 25.0 with little fear of pressure, but use your own judgement.
For example, for the ANDT method you would load 23.6 to 25.0 in 0.2gr steps should uncover your best options. Use their 2.244" COAL suggestion or try 2.250" for magazine length for a starting point unless you have a better one.

Here is a link to the target evaluation technique that explains the method very well.

https://www.snipershide.com/shootin...ns-accuracy-node-detection-technique.7175931/

My guess is with N133 and the SMK you will be happy.

Good Luck and in for the range report.