6.5 PRC load development data

[hollywood1981]

So got some range time in again with my new alamo precsion rifle. So here is what I'm working with thus far.

RE 26
ADG brass virgin
Federal gold cup large rifle primers

So i messed around with a new seating depth with 54.3 grains. This was a good velocity node i got on my previous lower velocity ladder test. I did a new ladder test to max charge weight with new seating depth.

Let me know what you guys think of the data attached. Thanks

 

[Gustav7]

You copied some stuff down wrong. The one ES is 23, not 7.

I'm not sure what input you'd like? Seating depth tests are usually used to tighten up groups, so what information did you want from the velocity strings?

If your chrono data is accurate then I guess 56.1-56.7 looks good with an ES of 19 across 0.6gr. But your chrono numbers look a little wanky.

 

[hollywood1981]

Wanted to get input on trying to lower the ES on the 54.3 grain loading, and also what you all thought on the top node on the 10 shot string. Thanks

 

[hollywood1981]

Here is a graph I did for the 10 shot string. I wanted to roll with 56.5 grains to see what it looks like. If good make adjustments to seating depths for better accuracy. Let me know, thanks.

 

[hollywood1981]

Need some input on this data I got guys please lol. Wanted insight from you experienced loaders. Do you see anything I'm missing or doing wrong? Someone point me in the right direction if you see any discrepancies or mistakes. All the input I can get is needed. Thanks

 

[Gustav7]

No one? Lol jeez not asking for much here.

You're not giving a lot of information man. The top three velocities of your ladder test APPEAR to be a node. But no one can give you information based off of just 3 velocities. If I were you, I'd load in the middle and shoot a few 5 shot groups over a chrono. See what the groups look like ,and see if the ES looks good over each 5 shot group and as a composite. Loads don't just appear out of thin air...you need to test what you find. If you're using a magneto speed, then you'll wanna do the ES testing separately from your groups..

As far as lowering your ES, prolly need more info...
How do you throw powder? What scale if its a scale?
Did you confirm consistent neck tension? If its virgin brass your neck tension may be off..
You may not be in a velocity node
Have you check it at distance?
You can try changing primers

 

[hollywood1981]

You're not giving a lot of information man. The top three velocities of your ladder test APPEAR to be a node. But no one can give you information based off of just 3 velocities. If I were you, I'd load in the middle and shoot a few 5 shot groups over a chrono. See what the groups look like ,and see if the ES looks good over each 5 shot group and as a composite. Loads don't just appear out of thin air...you need to test what you find. If you're using a magneto speed, then you'll wanna do the ES testing separately from your groups..

As far as lowering your ES, prolly need more info...
How do you throw powder? What scale if its a scale?
Did you confirm consistent neck tension? If its virgin brass your neck tension may be off..
You may not be in a velocity node
Have you check it at distance?
You can try changing primers

I am using a chargemaster 1500 for the powder throws, and then confirming the charge with a rcbs manual balance beam scale. As far as neck tension for virgin brass I just ran all of the brass thru my 6.5mm mandrel for consistency. Yeah the velocity node might not be there as well. I ran 54.3 grains on a previous ladder test I did. 5 shots with this powder charge with one seating depth at 2.295, and the other 5 shots with seating drpth of 2.285. The next 10 rounds i will test will be 56.5 grains with 2.285 seating depth and the other 5 with 2.275 seating depth. This will be for the accuracy test. I believe the velocity node to be somewhere between 56.3 to 56.7 charge weight, according to the data i got. I'm open to more insight from you and others please. Also thank you for responding.

 

[Gustav7]

I am using a chargemaster 1500 for the powder throws, and then confirming the charge with a rcbs manual balance beam scale. As far as neck tension for virgin brass I just ran all of the brass thru my 6.5mm mandrel for consistency. Yeah the velocity node might not be there as well. I ran 54.3 grains on a previous ladder test I did. 5 shots with this powder charge with one seating depth at 2.295, and the other 5 shots with seating drpth of 2.285. The next 10 rounds i will test will be 56.5 grains with 2.285 seating depth and the other 5 with 2.275 seating depth. This will be for the accuracy test. I believe the velocity node to be somewhere between 56.3 to 56.7 charge weight, according to the data i got. I'm open to more insight from you and others please. Also thank you for responding.

I would stop doing multiple things at once. Either find your seating depth first, via 3-5 shot groups going from .020"-.100" off the lands at the SAME powder charge. ORRRR, find your velocity node/optimal powder charge first. Confirm that node after your ladder test, and THEN do your seating depth test.

I'm also not personally a fan of the single shot ladder test for a relatively new reloader, myself included. Theres two many variables, and I don't have a nice chrono. I did do ladder tests twice repeated and it helped, but I ended up doing an OCW work up with 5 shot groups and that made it much clearer.

I would test your higher node your talking about for ES mainly.... the point is to find a stable powder charge. Accuracy can be tuned with your seating depth, but you need to confirm that your powder charge is not going to give you a bunch of vertical at distance. I would do that first, then tune your seating depth.

Good luck