.260 Remington Build by Southwest Precision - UPDATE: Load Development

[Gray]

These are the factory loads I plan on shooting for target and hunting.

They are the following, left to right in the picture:

1) Cor-Bon Performance Match 139gr Lapua Scenar (BC listed as 0.615)
2) HSM 140gr VLD Hunting (BC listed as 0.612)
3) HSM 130gr VLD Hunting (BC listed as 0.552)

The correct BC for the 139 Lapua Scenar is .578, which did not get posted by Lapua until earlier this year. I would try that and see what works. After I plugged the corrected BC into my Calc, everything fell into place.

 

[smorgousford]

I have never had good luck with HSM ammo, and don't recommend them to anyone. The 308 loads I tried had some crazy MV spreads, pressure issues (sticky bolt lift, cratered primers, ejector swipes), and were not accurate enough for match ammo (not even close to black hills, lapua, and GMM). I would think that hand loads would help greatly with accuracy, or just stick with the cor bon ammo. Just my experience, and opinion.

Interesting. I didn't notice any pressure issues this time around but the extreme spread is worrisome. I'm looking forward to HSM's call back with what they think of the data I took. I actually have a lot of the 139gr Lapua loads for target shooting and am only planning on using the HSM 140gr Berger loads for hunting (which they are plenty accurate for). I was able to hold 3/4 MOA off a bipod from 600 yards (my max hunting distance) so I'm happy with that! I will definitely be doing handloads in the future when I have a nice pile of brass built up.

 

[smorgousford]

You did a great job on your build sir! You definitely did your homework and it looks like you have a shooter there. You also did a great job on posting all the details before and after. I think you will be very happy with your choice in caliber, I know from experience that the .260 works well on elk sized game. Thanks again for the write-up and pictures.
Happy shooting!

Thanks! Glad to hear that you've taken some larger game down with a .260. Hopefully I'll blast one this fall...

 

[smorgousford]

The correct BC for the 139 Lapua Scenar is .578, which did not get posted by Lapua until earlier this year. I would try that and see what works. After I plugged the corrected BC into my Calc, everything fell into place.

Wow, that is quite the difference. I will definitely plug in that new value and see how that works. I was actually able to take some chrono data for the Corbon Match 139gr Lapua load yesterday and got the following:

Average: 2737 fps
Std Dev: 7.12
Extreme Spread: 16

So all in all, it was quite respectable in round uniformity.

 

[sierracharlie338]

Freakin sweet set up!


Sierracharlie out....

 

[Gray]

Wow, that is quite the difference. I will definitely plug in that new value and see how that works. I was actually able to take some chrono data for the Corbon Match 139gr Lapua load yesterday and got the following:

Average: 2737 fps
Std Dev: 7.12
Extreme Spread: 16


So all in all, it was quite respectable in round uniformity.

I too was using the old .615 BC and would get hits but had to always adjust a click or 2 to get the correct come ups. After trying to tweek the velocity to match what I was getting, I PM'd one of their sales guys whos on the hide and he informed me of the change to documented BC of the 139. After plugging it in, everything was perfect.

 

[7magsavage]

So I was able to get out nice and early this morning to do a little target shooting and extended chrono work. My main goal was to make sure the HSM Berger 140gr VLD Hunting rounds were dialed in perfectly out to 600 yards. I'm planning at shooting at elk out to that distance this fall here in Colorado. Conditions today were 19.55 baro pressure and 50 degrees F.

I got some surprising data from the chrono today. Here's the shot data for the HSM Berger 140gr VLD Hunting factory loaded rounds from my rifle (22" Krieger cut rifled barrel):

1) 2818
2) 2807
3) 2780
4) 2830
5) 2822
6) 2900
7) 2918
8) 2843
9) 2840
10) 2836

Average: 2842 fps
Std Dev: 40.12
Extreme Spread: 138 fps

While I'm very happy with the average velocity, the extreme spread is pretty big. I also can't believe there were two rounds at 2900 and 2918. The rest of the rounds were pretty close together except for the 2780 round.

Then it got even crazier when I tested the HSM Berger 130gr VLD Hunting and got the following:

Average: 2672 fps
Std Dev: 21.88
Extreme Spread: 58 fps

Some other notes from the shooting:
- I fired rounds from two separate boxes of each type of round to make sure it wasn't just one box that was having an issue
- The rounds were kept in the boxes in the shade prior to being loaded in the magazine
- I shot 3 to 5 rounds and then checked the target so the barrel was plenty cool between shots

I was expecting the 130gr to be faster than the 140gr, not average 170 fps slower! So I contacted The Hunting Shack (HSM) about my data and wanted to see what they said. Initially they told me that they expected the 130gr to average 2800 fps in a 22" barrel with the 140gr to be 75 fps slower (2725). I gave them the lot info from the boxes that I fired and they're going to see what they can find out.

Any thoughts on this or other similar experiences?

I was able to setup at 600 yards and dial in 3.3 mils (70.5") of vertical elevation (from my ballistics program) from my 100 yard zero and get the following 3 shot group laying prone on the ground with just a bipod:

Been there done that. If I were a betting man, I'd say that your chrono is lying. Probably passing clouds. (Makes a huge difference with my chrono). Completely overcast days always gave me the best numbers. I used to get really hung up on what the chrono said. I would get all bent out of shape when I would get those crazy numbers that just didn't make any sense.

My honest suggestion would be to do like I did and put the chrono in a box and forget about it.

By your 600 yard target, your ES isn't 175fps, not in those three rounds anyway! Not enough vertical dispersion.

What I'm getting at, don't think something is wrong just by the chrono when everything else says otherwise.

Great looking rig and backyard !
Congrats man!

Steve

 

[Cobracutter]

Those Pics make me miss colorado. My old Job had me out there a few times a year and I was amazed how it would be 80 in denver and 45-50 up in the mountains, with snow everywhere.

Too bad the libtards ruined the state. Time to find another place to spend my money. That is a sick rifle!

 

[565fitter]

jealous of the range

 

[smorgousford]

Been there done that. If I were a betting man, I'd say that your chrono is lying. Probably passing clouds. (Makes a huge difference with my chrono). Completely overcast days always gave me the best numbers. I used to get really hung up on what the chrono said. I would get all bent out of shape when I would get those crazy numbers that just didn't make any sense.

My honest suggestion would be to do like I did and put the chrono in a box and forget about it.

By your 600 yard target, your ES isn't 175fps, not in those three rounds anyway! Not enough vertical dispersion.

What I'm getting at, don't think something is wrong just by the chrono when everything else says otherwise.

Great looking rig and backyard !
Congrats man!

Steve

Good points. I'm done doing chrono work on this load anyway now. It will shoot dead on from 0 to 600 yards by my ballistics program so that's all I was looking for in a hunting round.

I hope to soon be able to do 0 to 1000 yards for the ballistics program for the Corbon Match 139gr Lapua round. That should be much better (especially now that I have the right BC thanks to Gray).

 

[smorgousford]

Those Pics make me miss colorado. My old Job had me out there a few times a year and I was amazed how it would be 80 in denver and 45-50 up in the mountains, with snow everywhere.

Too bad the libtards ruined the state. Time to find another place to spend my money. That is a sick rifle!

Yeah, I've recently stock up on a lot of 15+ round mags (even for guns that I don't currently have).

It is great when it's 100* down in Denver and 75* at my house! Winter is unfortunate with that temp difference though...

 

[smorgousford]

I was able to get out this morning and do a sort of practice run for a hunting scenario:

- I set up a target out far
- Walked back until it was out of sight
- Then with my pack on and carrying my gun I came out of the treeline
- Put the pack on the ground and put the rifle on top
- I lased the target at 280 yards
- Dialed in 1 mil vertical on the scope (left horizontal alone)
- I then shot a (10) shot group with no more than 4 seconds between shots

Obviously I wouldn't be shooting at big game for (10) shots but I wanted to practice quick target acquisition and firing as well.

Here are my results:



This was a pretty fun exercise and I'm going to keep it up with other unknown distances out to 600 yards. Laying on the ground in the ants with a dozen flies buzzing around your head offers another degree of difficulty!

 

[smorgousford]

So after deciding to use the HSM ammo loaded with Berger 140gr VLDH bullets, it looks like HSM is having supply issues and has indefinitely suspended production of the ammo. I really want to use the Berger 140gr VLDH bullet so I had to figure out another way to get this bullet in a round without loading it myself. This led me to Copper Creek Cartridge Company (C4) and the owner, Josh Lapin.

I told Josh what I was looking to do (use the 140gr VLDH and hit MV around 2800 fps) and we started with his Load Development Pack 1 where the powder is the variable between 5 different loads. Josh sent 25 rounds (5 of each different load) nicely packaged in a plastic reloading type container. The goal was to shoot a 5 round group of each load type and see what the differences were between them and which one worked the best in my rifle. He are the results along with a picture of the best group from 100 yards:






I was very pleased with the groups and velocities that I was getting out of my 22" Krieger barrel. I decided to take it to the next step and get the Load Development Pack 2. With the 2nd pack the variable is the Cartridge Overall Length (COAL), basically the bullet seating depth. Here are the results from the 2nd pack of 25 rounds:






Though the groups didn't tighten up, I was pleased by the increased velocity that was attained with the longer seated bullets. I've decided to have C4 quote me the rounds for the final Black group. I plan on using this for hunting of mule deer, elk, goats, sheep, pronghorn, coyote, etc.

I was very pleased by the entire experience with C4 (communication, results, shipping speed, pricing, etc). I highly recommend going this route if you know what bullet you want to shoot but don't have access to a factory loaded round, don't reload, and want to get something custom tailored for your rifle.

 

[4000fps]

You really need to load your own ammo. I believe I live relatively close to you. PM me if you want to shoot or learn to handload sometime...

 

[smorgousford]

You really need to load your own ammo. I believe I live relatively close to you. PM me if you want to shoot or learn to handload sometime...

Thank you for the offer and I may take you up on both. At this time though I really don't have the space, time or money to invest in it like I really want to do. I have quite a lot of Cor-Bon Match 139gr Scenar rounds for target shooting that came loaded in Lapua brass. My plan is once I go through all those target rounds then I'll have a bunch of Lapua brass and then I will start down the reloading path.

Why I did the Copper Creek route was that I knew I wanted to use the Berger 140gr VLDH for hunting and I didn't have a source for loaded ammo. Copper Creek loads the 140gr VLDH and custom tailored a round for my rifle. Now for the hunting that I will do for the rest of the time for this rifle (unless needing rebarreled) I know exactly what round to use and where to buy it from. And if I provide the Lapua brass to Copper Creek to have them reload then it's VERY cost effective.