Load Development Ruger Precision Rifle .243

[jdmecomber]

This post is intended to save a new reloader time, money and energy and show how we produced a sub 1/2 minute factory gun with extreme spreads less then 20 fps
If you have any questions or advice, we are happy to try and help you get past the learning curve
[email protected]
[email protected]

A huge part of this data is how we started with just full length sizing and no other Bench rest techniques and then switched to all bench rest techniques. A big difference on average 30-50% better group size, 30-50% lower on extreme spreads, and eliminating flyers from the groups

The Berger Bible (manual) will help you tremendously with developing a load.
Tubbs reloading video part 1 and 2 on youtube is your next stop even though its 18 years old it's great
Sniper 101 on youtube will teach you more about shooting than anyone else can for free it's like 87 part video series

All this being said, our goal was to develop a sub ½ moa load that was consistent at least 5 round groups and an extreme spread of less than 20 fps. Both were accomplished but it took over 8 trips to the range and over 320 rounds sent downrange. I will attach all stages of development and our thought process through the testing.
Ruger Precision Rifle .243 with a Vortex HST 6-24 Match rings and level, atlas bipod
Lapua Brass
We are shooting the 105 vld, and tried over 9 powders

I didn't read the berger manual till after the testing, I wouldn't have tested so many powders. I would have found a few with good fill ratios and velocity and just tested those, berger will tell you most powders can be developed into a good load and all powders are temperature sensitive. '

We tested 9 powders, IMR 4831, 7977, 7828, 4350, 4064, Extreme powders retumbo, h1000, h4350 H4831 SC, and many different primers, S&B, 210, 210m, 200, 200 Br, 215, 215m, 250

We started at .026 from lands for one reason because the Ruger Magazine can handle .015 from the lands but that's about it and the bullet tips are scraping the magazine

Velocities were tested with a Magnetto sporter which is great, those 100$ chronographs are junk is what were found out. The magnetto does appear to have some effect on your bullet

All powders were a grain off of Berger Bible Max Load

100 yard
All four round groups except H4831sc
IMR 7977 average about 2900 with 48 ES 1.8 MOA
H4350 2700 63 Es 1.5 MOA
IMR 4350 2840 ES 29 .9 MOA with rounds almost identical ES
IMR 4831 2800 ES 51 .69 MOA
H 4831 SC 2870 ES 64 .394 MOA 5 round group submitted to the ruger challenge Number 7 100 yards 5 shot
H1000 2900 ES 50 1.2 moa
RETUMBO 2970 ES 49 1.0 moa
IMR 7828 2800 ES 25 .600 3 bullets less than .250 moa

So H4831SC factory gun, shot lights out so why not just stop. Its extreme spread is horrible so lots of development to go

So the next test was to see an Optimal charge weight test with H4831
because it was the most accuarate

Research OCW needs to be done
Low powder charge to close to max and your looking for a load that when temperatures spike or get colder are still hitting on the same horizontal plane
That first group shot high so the scope was adjusted down
OCW 1.1, 2, 3
.702 moa, .605, .586, .799, .675 from 42.3-43.4 grains of powder

There are 6 more stages to post time. I will try and update daily

 

[Tnwhip]

One more powder to try is H100V. 40.5 with 105 A-max gives me 3066 fps and SD 14. with .700" group. I quit at that for now and just went hunting. I will do more testing this summer

 

[barefooter56]

jdmecomber,
Read pages 100 and 101 , Effects of cartridge overall length (COAL) and Cartridge base to ogive starting on page 148 and Basic statistics for Hand loading chapter starting on page 140 in your BERGER manual for some help with your load testing here. Will be watching for any questions you may have on this .
Take care!

 

[buckfvr]

I will add to Joes info here and there as he goes through all parts of this post as I helped develop and shoot through out.

There is going to be more powders that can and should be tested per each and every ones preferences. What you can get out of this post, provided you follow it to the end, is mostly arriving at a suitable for you conclusion to your own testing WITHOUT a bunch of unnecessary tail chasing through out. We did that for you.

Once we moved on from the full length sizing , and transitioned to full uniforming of brass, we leaned heavily on Bergers manual. We left no stones unturned near as we could tell. The dramatic improvement in our results is worth sharing. Even though looked at casually, a quarter of an inch here and there, ten to twenty fps here and there, seem kind of inconsequential.......until you realize that is how you get from .6 or .7 moa to under .5 moa. And I mean under .5 moa often.

Follow Joes post for more details and help, we are only trying to help those who need a bit, as we know there are plenty of guys who are above this part of the learning curve, but may be so a few guys can get a few pointers. Russ

 

[jdmecomber]

I have no questions at this point, our SD of our final load is 6. We used the manual a lot. Our final test will be two powders head to head. They both are producing very similar .40-.50 moa 5 round groups and in the teens ES.

So after the original powder test IMR 7828 and H4831SC
7828 coming in at .600 moa 4 shots and H4831 SC at .394 moa 5 shot group

We wanted to just shoot a couple groups with those two best performing powders and also from the OCW test it appeared nothing was spectacular but we wanted to try 4831 again at 42.5 because of the .394 moa group with a different primer. Russ and I trade off on shooting groups to make sure results are spread out between two shooters. I took some of my loading gear over to Russ' place and found out that my powder scale was off at his place because of the elevation. Good tip if your moving gear from one to the other

Tested

7828 43.5 grains .578 moa 4 shot with a 34 ES

7828 44 grains .687 moa 4 shot with 3 rounds only 7 fps apart 53 ES

H4831 43 grains at .800 moa 4 shot with a 31 Es 210 M primer

H 4831 42.5 grains 1 moa 5 shot 4 within .350 moa BR CCI was not chronographed


I think one of the big issues I have always had with reloading is consistency. One day your rounds and gun shoot very well and the next its different. It gets frustrating.
After this test, its still nothing great and extreme spreads are not where we wanted them to be and we couldn't duplicate the .39 moa group

 

[jdmecomber]

We decided to try a lands test with H4831SC, We looked at the OCW test again and decided to try 45.8 with multiple lands tests and of course tried 42.5 again

Three round groups Lands testing
We tried 42.5 at .015 .505 moa
and 42.8 just didn't seem to work
.015 .95 moa
.021 1.10
.026 .912
.040 .88
.060 .858
.080 .67

Not impressed, still nothing was working

 

[JJMoody]

Throwing a little thanks your way. Following your process and learning along the way.

 

[buckfvr]

Winter is a tough time of the year for duplicating things and finding consistency, We now log temp, humidity, and baro at the beginning of each shooting session, and at about the half way point ....just as a reference since conditions change so fast here.

We are shooting out of my shop, bench rest through a shooting port, with a fire in the wood stove, so its comfortable, but still very cold on the gun at the shooting port. We try to control as much as we can for the sake of consistency, but its very difficult.

We know development requires fine tuning at each season, and since we shoot all year, we are constantly aware of changing seasons and the requirement that entails.

In addition, for the sake of interest, we are shooting off a bipod and rear bag.

 

[jdmecomber]

It appears 7828 has been giving us consistent .600 moa groups so we decided to do an OCW test with that. The extreme spreads have also been pretty decent
We started at 43 grains and went to 44.2 grains

43 grains 43 es .580 moa
43.3 9 es .624 moa
43.6 4 es .785 moa a primer failed only two shots
43.9 53 es 1.3 moa
44.2 67 es .343 moa average speed 3000 fps

So 7828 had high exteme spreads with 4 groups under an moa and a decent ES at 43.3
One thing to note is all those powder charges are printing on the same horizontal plane

We also tried some 210 primers with H4831sc
4 shots at 42.5 gr with a 15 es but the group was .94 moa

We also tried some 200 cci with H4831 sc
4 shots at 42.5 gr with a 28 es and a group of 1.2 moa

The reg 210's and CCI both beat the 210 match primers substantially but the groups opened up quite a bit


My buddy recommended we try imr 4064 with cci primers. The 4 shot group was bad but the ES was 3027,3024, 3026, 3000 and we thought that was pretty impressive so why not try an OCW test

 

[jdmecomber]

forgot one

 

[jdmecomber]

4064 showed some promise we did an OCW test, I wont post all the pics just a couple highlights.
One of the problems with this powder was at 37 grains it was going 3000 fps and we really didn't want to have that much speed because of barrel wear and we are loading in the winter, so in summer conditions this load would be well over max pressure
we test 35.8-37 grains at it was all over the place so it was showing signs of instability

35.8 .664 MOA
36.1 1.11 MOA
36.4 .432 MOA
36.7 .731 MOA
37 .882 MOA

We started getting away from the magnetto at this point when we wanted to try and shoot for groups we figured it had something to do with weird harmonics

Not sure why the pictures are crooked

 

[buckfvr]

SO there seems to be two camps where powder is concerned.......I'll stick with say 4064, been usin it for 40 years and its always worked fine.....vs. Its called Extreme Powder for a reason, so Im using that !!!!! Wrong. Forget about old reliable and advertisements and just test and compare. Read up on powders and learn just how similar they are with in a burn rate......read about primers, and how they work with different burn rate powders......make learned decisions on what to test and what to maybe test another time. Read about case capacity and case volume by powder type. You have to be somewhat more analytical than you'd think, but it will show in the end whether your choice was good or bad.......dont settle for good enough, go for great.

 

[jdmecomber]

So at this point we both had done a bunch of research on the subject of reloading.
We had good extreme spreads and bad accuracy or good accuracy and bad extreme spreads something had to change.

We found that my RCBS chargemaster would throw heavy and light loads of powder, nothing was exact. I figured that the heavy and light loads alone could be giving us 20 feet per second spreads alone. So I researched scales, the best scale for the money we could find was a GEMPRO 250 these things are great. You can get your powder down to .02 grains they are very accurate. They are about 127$ on amazon.

We knew at this point we had to try something different so we decided to get into more of the bench rest portion of reloading, so I bought a forster bushing bump die with .266, .268. 270 bushings. We bought a 44$ tube micrometer from amazon which was money well spent along with a Grizzly stand for it 25$. We figured our necks were .015 so we turned our brass to .013x2 + .244 diameter= .270 so we used the .268 bushing.

We cut our Hornady modified case so it could do chamber length and also OAL

I also didn't really care about headspace during this whole testing, but decided we needed to do it and try to get the most out of this rifle. So I tested headspace, I noticed a couple of the rounds I had already done were off a little so now I will neck size the brass and rotate it 180 degrees and size it again. .003 headspace

I also make sure when I seat the bullet I slowly start it half way rotate it 180 degrees and seat it the rest of the way for almost perfect runout

Now I decap my brass, uniform the primer pockets and debur the flash hole, then wash it so the brass isn't dirty when it goes into the die.

Chamfer and debur

Something I did with primers after reading a great article. I sorted them by mass. Yep I spent the time and weighed my primers and I have to say its working or maybe its just all the other stuff

So here is the first test we tried
Full length sized no bench rest vs Bench Rest my way

We shot 6 round groups to really give it a real test, the funny thing is the first three shots of the full length group shot about .250 moa and the next three ended at 1.20 moa. That ended my reloading career only using three rounds for any kind of test

Full length
6 rounds 1.2 moa

vs

Bench Rest

5 rounds were .518 moa with the 6th at .864

Its very easy to tell from the pictures that the bench rest techniques almost took away all the flyers

 

[jdmecomber]

I will post more tomorrow with the Bench Rest techniques we used on H4831SC and IMR 7828