260AI roll call

[Bill Norris]

I shot the 140VLDT from a 26" barrel with 47.5gr H4831 at 2975fps.

That is right there with my 40X Berger 140 gr. L R Target load with 44.8 GR. H-4350 @ 2971 fps.

 

[STOMP442]

43.5gr of H4350 or R-16 has always given me excellent results out of 26" 8 twist barrels with 140s in the 2920-2950fps range. 46.0gr of R23 also shot very well for me.

 

[6MMsteve]

I don't really do velocity anymore just paper, maybe I'm missing something

 

[Bill Norris]

I don't really do velocity anymore just paper, maybe I'm missing something

I pay it very little attention as well. Once I check it after the load is developed to see where it's at with muzzle velocity I'm pretty much done with it. As Erik Cortina says "Believe the Target". Not to say chronos are of no value but the main reason I don't pay it much mind is I've seen 5 shot groups with over 100 fps difference that were really tight one hole with extreme E S & S D numbers and 5-shot groups that were open with single digit E S & S D numbers with more than one chronograph.

 

[Fast14riot]

Bringing this back up. I'm running out of RL23 and needing to switch. I have a decent supply of H4350 and currently shoot the Berger 153.5. Anyone shooting the 150 class bullets with H4350? Didn't see it listed here.

 

[mikecockcroft]

44.0 gr Ramshot Hunter w/ 140 gr bullets

 

[bas402]

Bringing this back up. I'm running out of RL23 and needing to switch. I have a decent supply of H4350 and currently shoot the Berger 153.5. Anyone shooting the 150 class bullets with H4350? Didn't see it listed here.

I'm curious on this as well for the 156 Berger

 

[Heman]

Building one for NRA LRP, have a .243 and .280 decided I needed a 6.5mm so between the three can find bullets. Using a tone of once fired Lapua 260 LRP brass I got. Have a 1:8 32" brux. Wasn't sure on the Redding dies so getting a set made by Hornady on my reamer print. Going to run N160 hoping to get 2950ish with 140s.

 

[Fast14riot]

Did a little digging around the interweb, found some info about H4350 and heavy bullets. Looks like right around 44gr under a 153.5 is where most end up.

 

[bks22345]

Did a little digging around the interweb, found some info about H4350 and heavy bullets. Looks like right around 44gr under a 153.5 is where most end up.

I run 43.1 in a straight 260 with 153.5s, H4350 and virgin Peterson. I ran up to 44.6 with good groups but I was getting ejector marks. The shoulders were moving quite a bit. I may take another look once I get through the first firing on all of it.

 

[Fast14riot]

That coincides with the 44gr in a 260AI. I'm going to run the numbers in GRT and compare to my current load and see what it says. I shoot a lower node barely over 2800fps with the 153.5.

 

[Bill Norris]

I run 43.1 in a straight 260 with 153.5s, H4350 and virgin Peterson. I ran up to 44.6 with good groups but I was getting ejector marks. The shoulders were moving quite a bit. I may take another look once I get through the first firing on all of it.

Yep I can see clearly why the brass was getting beat on. 44.5 to 44.8 gr. of H-4350 with the Berger 140 gr. L R Target is on the warm side with my 260AI.

 

[Fast14riot]

Doing a little more looking at viable replacement powders to push the 153.5, N555 is available and I like the price. I know its the go-to for the 284 guys which puts it in the right ball park. I may just order a keg and try it. I'm thinking right between 43-44gr should do it.

I did run the numbers in GRT for H4350 and the 153.5, it says 44gr is the node but pressure is starting to get high (calculated 58,500psi) and velocity is right where I'm currently shooting at 2825fps.

 

[Fast14riot]

Ended up ordering a keg of N555 because I needed a keg of Varget too (for multiple 6br rifles) and found them both in stock in one place. My other option would have been to go back to H4831 but at $400 a keg i wasn't overly excited about it.

GRT says 45ish grains should get me to my node around 2830. Hope to start load development with it soon as I have only about 3-4 matches worth of RL23 left. This keg should be enough to finish off this barrel then time to spin another one up!

 

[Bill Norris]

A friend of mine recently purchased 8 lbs. of VV-N555 for his 6.5 C M and I worked up a really good shooting load with his newer pointed Sierra 142 MKs with it. Chrono says 2732 average M V for 5-shot groups so I'm certain there is some room at the top. I have a powder test loaded for my 40X 260AI with the 140 gr. Berger L R Target to see how it acts. Hoping to check it out once the rain is out of here.

 

[Fast14riot]

Shot a 3x600 today with the 153.5 and RL23 (hoping the N555 gets here soon, i have <1lb left). Took second with a 588-25x and first was a 589. Match 2 had some squirrely winds and a left/right switch made me miss a shift and shoot an 8 just off the line. +9.75 moa from zero to 600y.

 

[Infrequent Shooter]

Shot a 3x600 today with the 153.5 and RL23 (hoping the N555 gets here soon, i have <1lb left). Took second with a 588-25x and first was a 589. Match 2 had some squirrely winds and a left/right switch made me miss a shift and shoot an 8 just off the line. +9.75 moa from zero to 600y.
View attachment 1538764View attachment 1538765View attachment 1538766

great shooting! nice range too.

 

[Fast14riot]

Got a 3 shot powder test ladder done today, using a new lot of Berger 153.5 as well. I know my seating depth and it held up for this lot, too.

Peterson 260SRP ~10x firings
Ginex SRP
Berger 153.5 seated to 2.433" BTO
Vhitvouri N555 43.8gr-45.8gr 0.4gr steps

Target 4 is 45gr and target 5 is 45.4gr. Target 5 i got a little gust of wind and blew the 3rd shot out to the right. No velocity measurement yet. Will get that from the next match. GRT says 45gr is right about 2825fps, right where I normally shoot this bullet.

 

[Bill Norris]

Planning to test the Sierra 142 MK soon in my 260AI with VV-N555. Hoping for some good groups as well with it.

 

[Fast14riot]

Planning to test the Sierra 142 MK soon in my 260AI with VV-N555. Hoping for some good groups as well with it.

I was pleased with the overall accuracy, and suspected the 45gr load is where I wanted to end up. I shot 15-20 rounds of fire form and old 140VLDT loads i had left over to foul the barrel. Then shot 9 rounds of ladder and let it cool before finishing. Barrel never got hot. Will clean it tonight and see how it looks. Supposed to have anti-fouling properties so we'll see.