5 replies to this topic

[A17Shooter]

When I had my 204 built, I spec'd a 1 tn 9" twist barrel so I could shoot the 50 gr Berger LD bullet. The action used is a trued Rem 700 with a single shot adapter There was some reloading data available but, it didn't seem to be what I wanted. When you have a long heavy bullet, for the caliber, it seems to me that it should also have a relatively slow powder. None of the load data that was available provided a slower powder load. As I had WW760 on hand and was familar with it's characteristics that was my powder of choice. Unfortunately, the load manuals and the various web sites for reloading did not show any data for WW760. WILDCATTER, FLAME ON! Whoops get carried away. At any rate I started low and worked up. Currently I have loaded and tested seven 0.5 gr increments for pressure signs and accuracy. Have also chrono'd several of the loads. Currently the loads are yielding about 3500 fps and the four loads tested yesterday yielded three shot groups that ranged from .342" to .411". Didn't set the chrono up yesterday as the wind was gusting heavily and I thought it would blow the tripod over. Just wanted to admit that the 3500 fps was a guesstimate based on the previously chrono'd loads. The pressure signs still indicate a moderate pressure level by observing primer extrusion/flow, checking for sticky bolt lif and examining the case head for shiny areas on the bottom. There seems to be enough case capacity for a few more half grain increments of powder charge.I am hoping to reach a maximum velocity close to 3700 fps. I'm still hoping to find a real advantage for the Berger bullet over the Vmax & the BlitzKing. If you take the published BC figures at face value there isn't much difference in trajectories between the three. But the BC numbers aren't always absolutely correct and computer printouts don't tell the whole story. The goal is to have a remaining velocity of 1800 fps at 700 yds. Currently the Sierra ballistics program predicts a velocity of 1605 fps with a MV of 3513 fps. So, onward and upward.

[Cranky Farmer]

That would be a great coyote load. Sounds like you've spent a lot of time working on that load and it sounds like it is paying off.

[Frank]

A17, 3700 fps is pretty optimistic velocity in that bullet weight... Especially with W760, as it is just too slow a burning powder for that set up IMHO... but of course, the proof is always in the pudding... So??Varget may be a little better, however, IMR 4895 & RL10X would be at the top of my list to try. RL10X has given me both the highest velocity (@ 3700 fps) & best accuracy with the "40" gr Nosler Ballistic Tip bullet.You have quite a project there, and good luck in your ventureFrank

[A17Shooter]

Well, the 760 load development experiment, Phase I, is complete. I assembled six more load tests for firing and proceded to the range with chronograph, rifle, notepaper and targets. The test loads were assembled with three rds for each load level. The powder charges were weighed in 0.5 grain increments. Tip of the Day: You can judge when your powder charges are starting to be excessive by measuring the case just in front of the extractor cut. The procedure is to measure the case before and after firing. Excessive expansion in this measurement is an indication of extreme pressure. Supposedly this only works with brass that has already been fired at least once. An increase in the base measurement of 0.001" is considered excessive. Note: Excessively annealled brass will also result in excessive base expansion and is still a danger sign, just the cause is different.Tip of the Day #2: If you have heavier than normal bolt lift after firing, you are probably experiencing excessive pressure. Tip of the Day #3: When your primers seat with very little or no force after two or three firings, it probably means you are in a high pressure situation. Dump those cases with loose pockets and start over. Don't do like one fellow I heard about and just use a little scotch tape to hold them in. Back to the load test. All the cases were once fired Hornady brass. The bullets were Berger 50 gr Match/Varmint. The case expansion measurements were taken at home after the test firing.Load #1: AVG - 3460, SD - 32, Grp - .57, Expansion - .371Load #2: AVG - 3503, SD - 15, Grp - .95, Expansion - .371Load #3: AVG - 3567, SD - 33, Grp - .58, Expansion - .372Load #4: AVG - 3628, SD - 33, Grp - .67, Expansion - .375Load #5: AVG - 3689, SD - 27, Grp - 1.26, Expansion - .375Note: Heavier bolt liftLoad #6: AVG - 3748, SD - 29, Grp - 1.04, Expansion - .379Note: Heavy bolt lift. Blown primer on last round. Too much! Last case stuck in bolt, had to beat it out.Lessons learned:1. Take calipers to range for load tests.2. After you get high pressure signs, stop.3. You can get too much 760 behind a 50 gr bullet in a 204 Ruger.4. Powder particles in the face sting, wear safety glasses!5. Load #2 has possibilities. Two of the three made a small figure eight.6. Not likely to get 3700 fps with the 50 Berger as a safe load with 760.Just thought I'd share this experience as what not to do, since some people have been talking about starting to reload.

[DEERSLAM]

Some very good info....and tips, ouch. I'll be interested in what you come up with as far as loads with the 50gr Berger and how they perform on yotes.

[A17Shooter]

We'll keep you posted. I have to start working on sorting out the best load for accuracy now. Then see if I can get a yote to cooperate.