Load Development Ruger Precision Rifle .243

[buckfvr]

Brake down and ask your wife to help you.....

 

[jdmecomber]

Another thing we figured out is a 2-4 mph wind could move your bullet .1-.2 inches so if the wind is blowing and your trying to shoot a .4 inch group. Results most likely will not be what your looking for, just something to think about

 

[jdmecomber]

Tuesday we should have the final results posted.

 

[jdmecomber]

We had some wind today. It was 35 degrees. A little cold
A couple highlights from today.

 

[jdmecomber]

Russ stacking up some bullets

 

[jdmecomber]

A 7828 group

 

[jdmecomber]

So I ran out of 7828 regular, I substituted 7828 SSC at the same grain weight as 7828 42.8. The Super Short Cut was about 40 fps slower then regular cut.

Russ and I have went back and fourth with which powder could be said is the final winner for my gun. They both performed very well. The standard deviation of ten rounds for H4831SC and 7828 were both around 7. Our final velocity spreads were 15-25 feet per second with only one round out of ten sending it out of the teens. We decided on H4831SC.

Our final decision was decided based on H4831SC shooting 5 round groups at 100 yards at .394 moa, .408 moa, .508 moa, .632 moa. A couple of these groups had four rounds within .250 moa or smaller.

Our final round count was about 332 rounds, I have only run about 4 patches through the gun to clean it and we used a bore snake maybe 4 times. I don't clean my guns until the accuracy starts to fade or it gets wet. You can look up copper equilibrium if your curious why we do that.

Well I bought this rifle for 970$ when they first came out, 1/2 moa doesn't seem too
impressive compared to a 5k custom gun with a 1/2 moa guarantee. I think this shows a guy that can't afford a custom gun that this rifle with a little bit of reloading knowledge can get you a very capable reliable gun shooting some of the best long range hunting bullets on the market.

Take Care
Joe

 

[buckfvr]

So this is the culmination of our efforts to find better consistency from one loading session to the next, in the development of a load in .243 for the Ruger Precision.

We determined that as a reloader, you must take every step there is to uniform your brass, if you are looking for the most out of a factory box gun. There is no substitute for quality components and tools. And you must use accessories for the gun to your benefit, like a high quality scope with a level on it.

We shot exclusively at maximum 24 power on a 6 - 24 x 50 Vortex scope. If you dont use a leveling system when installing a scope and level, even the slightest cant introduces windage to your group. The farther you shoot, the more this increases.

As I said before, we shot from a bench with a bipod and an assortment of rear bag configuration. Joe liked one set up, I, another. There was some obvious shooter influence on some the the shots, but we are just normal guys like everyone else.....we are still learning and will continue to learn for some time. We do feel our performance was well within an acceptable level of human error, which most definitely exists.

Hopefully someone will pick up a helpful pointer from this, or maybe it will spawn some ideas or motivate someone to keep going.

Joe and I both also shoot 7mm rem mags and are long into that development as well. We will be moving on with more testing for those, even though they shoot amazingly well as it is. Both factory Savage Long Range Hunters.......great guns.

SO, we hope this helps clear up some issues, and not confuse anyone.....good luck, Russ

 

[just browsing]

I just skimmed through the first 5 pages, so I may have missed it 115gr bullets are optimal for the 1:7.7 twist barrel if I'm not mistaken. Could be part of the reason that you struggled so much early on with the lighter 105s. I have a feeling that the longer VLDs would stabilize a little bit better through the fast twist barrel, especially over longer ranges.

Furthermore, the .243 is notorious for having random pressure spikes, especially with heavier bullets / different seating depths, different powders, and temperature variations, so there is also that part to consider for your ES results.

Interesting stuff to say the least, but thanks for your work consolidating all of your findings and posting them here for everyone else.

 

[buckfvr]

According the the stability calculator, the 115 Berger needs a 7 twist and the 7.7 in the Ruger is fine for the 105. Other thing is the 115 is so much longer as to be a problem in the Ruger unless you wanted to single feed as the inside dimension of the magazine box wont allow any additional length. It would not benefit anything to shove the bullet further into the powder column and that is precisely what would happen to load the 115 in the factory mags.

We paid strict attention to case volume in regards to our powder choices knowing full well the .243 is overbore. We feel initially, having not gone to great lengths to uniform the brass, resulted in the higher ES and SD. That came tolerably under control and we will test again later in more desirable weather to see if it isnt even better.

Plus, we also tested powder primer combinations to eeek out a bit better ES, and in the end did but its more likely the complete uniforming of the brass had the biggest influence.

Thanks for reading and sharing your ideas, much appreciated, Russ

 

[gunners]

Interested to know if there's a difference in all the practice the shooters have been having, so if you went back to the start of the load development and reshot a couple of those more promising ones, see if they shrink because you're "shooting fit" so to speak.

 

[jdmecomber]

I think it's huge. I really don't like shooting off the bench. I was just never really comfortable. I watched a lot of videos on recoil management. It was neat to see how Russ' groups were different then mine by .20 inches or so. I got my savage 7mm mag shooting really well but the first shot was always .750 off then the next 3 or 4 rounds would stack up. I called up a local competition shooter and asked him about cold bore. He told me it was mostly cold shooter, so I then went on to see if I could actually fix it. I can tell you for me and that 7mm it was 100% me. I will call it COLD SHOOTER SYNDROME. . I now sit behind the gun, Take a couple dry fires get comfy and slow down. I think Russ has CSS once in a while. He probably wont admit to having this disease I will attach two groups where the cold bore shot just doesn't make sense. 4 or 5 rounds stacked near each other and a flyer. Wind was not a factor.

 

[Tnwhip]

I bought some Hunting 115s and I found out that they were just too long. The throat was very short and I didn't want to seat them that deep to make them work. I like the 105 A maxes. Seat them to mag length and go. The one thing that surprised me was the 65 g V max. I had some and I tried them just to see how they would do. I loaded 5 with 46g of win. 760 and shot a .570 group. I am going to load up some more and do more testing. I think that is going to be my varmint bullet. I was wondering how they would do with the fast twist but mine seem to shoot everything from 65, 70, 75, 85 and 105 really well. The Sierra 75 hp shot a .490 and 85 GK .500 and the Hornady factory load 95 sst super formance shot .780 group. This has been most forgiving rifle I have ever had.

 

[jdmecomber]

The other cold bore

Another thing to consider.
Those 4 five round groups
Group. .394. 4 at .196 moa
Group. .408. 3 at .210 moa
Group .508 3 at. .118 moa
Group. .632. 4 at. .183 moa

70% were below .210 moa

1 out of 20 rounds thrown out of our goal of 1/2 moa