First 260 Load Development Chronicled

[hondo1312]

First of all, many thanks to TresMon for demystifying hand loading. I was able to shoot my first 11 handloads today whilst keeping all my eyes and fingers, and gathering some much needed data to continue. Now, I need help from the experts on what to do next.

Here are the results of my ladder test conducted at 283 yards:

From reading the stickys, I think I need to run another ladder test in 0.3 grain increments from 40.5 to 43.5 grains. What say you guys?

I'm shooting 140 Hybrids over H4350 out of a 260Rem with a 1 in 8 Bartlein and TBAC 30BA can. Any guidance would be tremendously appreciated!

 

[rduckwor]

You range looks right to me. Yours is one of the better ladder tests I have seen.

Good luck

RMD

 

[RampedRaptor]

Was that 43.5 a pull/ gust of wind or a true shift. I like 43.0 if 43.5 was a pull/wind. I would retest as you plan but I will agree it looks like a nice test example. .

I ran ocw test on my 260 and ended up running with 42.9gr of h 4350.

Best of luck

 

[hondo1312]

I got out today and ran the second ladder test from 40.3 grains to 43.6 grains in 0.3 grain increments. Test was shot at 572 yards; 75 deg F, 75% rel hum, 28.97 inHg absolute pressure, wind at 4-6 mph from 9:00. I started shooting about 7:00 am. My wife was with me to drive the 4-wheeler back and forth to mark the targets after each 5 shot string. The first shot of each string was a 136gr Lapua Scenar-L, purchased from Southwest Ammunition. It was fired at a steel plate above the paper. I included that 3-shot group as well, because, for me, it was a pretty awesome group, even if it was only 3 shots!

Ladder test - each hole is marked with charge weight and muzzle velocity from a Magnetospeed V2.

Ammuntion is SSA brass trimmed to 2.030, Winchester LR primer, and Berger 140 Hybrid seated to 2.870.

3 shots with 136gr Scenar-L from Southwest Ammunition

I think next weekend I'll load up some rounds at 43.0, 43.3, and 43.6 and shoot them at the same distance to see which one groups the best, then start playing with seating depth after I determine which load I'm going with.

If anyone has any suggestions, criticisms, etc., please chime in. Thanks!

 

[hondo1312]

Went out and shot 3 10-shot groups at 600 yards today; I think I've settled on 43.3 grains of H4350 (at least until I run out and get to start over).

Average muzzle velocity: 2886 fps
ES: 36
SD: 12

Because I'm new at reloading, I loaded all rounds to 2.870 OAL, not recognizing the difference in bullet lengths from the ogive to the meplat. I loaded up 5 sets of 5 rounds for tomorrow, backing down base to ogive length in 0.010 increments. By my calculations, I'm starting at 0.059 jump due the length of the 140 Hybrids and limiting length of the AICS mags.

10 shots at 600 yards with 43.3 gr H4350: (sorry for the lack of reference measurement)

 

[hondo1312]

Well, this morning was a disaster. Out of my first 7 shots, 3 primers fell out of their pockets and I had sticky bolt lift. I guess I'll back down to 43.0 grains and try again.

Oh, the joys of being a newb hand loader!

 

[BoilerUP]

If you can, try CCI-200s in place of the WLR.

I also note 43.3gr was a lower velocity than 43.0gr in your ladder picture in post #4.

I'm not any expert reloader, but I suspect you'll find OCW at 43.0gr +/- 0.1gr.

 

[Fried Chicken Blowout]

Has anyone run into an issue with doing load work ups with the Magnetospeed hanging off the barrel and then finding out there was a change in the node when you removed the Magnetospeed? I just noticed the OP was using one and I was interested in doing the same but not if it caused a change in harmonics being on there.

 

[ShtrRdy]

Has anyone run into an issue with doing load work ups with the Magnetospeed hanging off the barrel and then finding out there was a change in the node when you removed the Magnetospeed? I just noticed the OP was using one and I was interested in doing the same but not if it caused a change in harmonics being on there.

I don't have direct experience with this, but it doesn't surprise me that the Magnetospeed will change the barrel harmonics. You can think of the same effect as the Browning BOSS where changing the weight hanging on the end of the barrel will change the barrel harmonics.

 

[ShtrRdy]

Well, this morning was a disaster. Out of my first 7 shots, 3 primers fell out of their pockets and I had sticky bolt lift. I guess I'll back down to 43.0 grains and try again.
Oh, the joys of being a newb hand loader!

I thought maybe that load was a little on the hot side. I'm running 41.1 gr of H4350 behind a Berger 140 gr VLD and getting 2750 fps. It's not a screamer but it's very accurate and easy on extraction - and brass.

 

[hondo1312]

Has anyone run into an issue with doing load work ups with the Magnetospeed hanging off the barrel and then finding out there was a change in the node when you removed the Magnetospeed? I just noticed the OP was using one and I was interested in doing the same but not if it caused a change in harmonics being on there.

The first ladder test was shot without the magnetospeed; the second ladder test was shot with it. The spacing of the nodes from the second ladder seem to coincide with the nodes from the first (at a glance...to me...for what that's worth).

I think the next time I do load development, I'll leave the chrony at home as not to be influenced by the results of muzzle velocity. The reason I went with 43.3 grains instead of 43.0 was 43.3 had better SD and ES. At this point, I can't shoot the difference in what they were, and think I wasted a trip and components. The 43.0 grain was group was just a hair over MOA at 600 yds.