260AI roll call

[Bill Norris]

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.

Please keep us posted with your results. I will return the favor as well.

 

[Fast14riot]

I'm going to shoot a 3x600 match Sunday 4/14 and will shoot 45.2gr N555 with the 153.5 for a long range test before taking it to 1000y. Normally I shoot one of my 6's at 600, but this will be a perfect opportunity to test.

Of course, will update after the match.

 

[Bill Norris]

I'm going to shoot a 3x600 match Sunday 4/14 and will shoot 45.2gr N555 with the 153.5 for a long range test before taking it to 1000y. Normally I shoot one of my 6's at 600, but this will be a perfect opportunity to test.

Of course, will update after the match.

Very nice. Thanks.

 

[Liven The Dream]

Back in 2006 to 2008 260 imp Prone Rifle Pre War 70 Action 30" R-5 Obermeyer Barrel 1-8 ?
Brass 243 Winchester Wolf LR 4831SC 43.5 142 Match Kings.
Most like one of my most Accurate Rifles.
2008 State Long Range Winner. 600 yard a 597 and a 596 .
I just gave up on Fire Forming and short Barrel life for Long Range Rifle.
Fire Forming load R-19 at 600 yards a Win ? R-19 after Fire Forming never worked.

 

[Fast14riot]

My fire forming load is 44gr H4831 under a 140. Shot it in many 600y matches with success. I've never shot RL19 in the 260AI.

 

[Bill Norris]

My fire forming load is 44gr H4831 under a 140. Shot it in many 600y matches with success. I've never shot RL19 in the 260AI.

A friend of mine is loading RL-19 under 120 gr. class bullets and shooting lights-out in his 260AI but it does not perform as well with the heavier 140 gr. class bullets.

 

[Bill Norris]

Shot a powder test with the 142 Sierra MKs. Plan to check with 5-shot gp. for duplicate soon.

LAPUA BRASS
142 GR. SIERRA HPBT MK HBN C 2.199 O M 2.865 COL T/L B S .511 B C .626
POWDER VV-N555 3-45.7 3-46.2 [3-46.7] GR. PRIMER CCI BR-2 .290 BUSHING .261 EXP.
SEATED @ 2.194 O M 2.860 COL .005 OTL
46.7 GR. BEST 3-SHOT GP. MEASURED .224 2941 FPS 21 E S 9 S D
76 DEG. 56 % REL/HUM

EDIT: From looking at my brass and primers looks like I still have some headroom with the powder. I'm thinking it will probably max. out @ around 3000 fps.

 

[Fast14riot]

Shot 45.1gr N555 under a 153.5 Berger at a 600y match today. Really happy with it, very consistent. All the dropped points was me, wind swirling and flags pointing at each other, after a 90 minute rain delay this morning. Ended up needing about 10.8 moa elevation with this load. RL23 I typically needed about 9.8

Managed to pull out a 4th place finish with a 591-24X. Load was very consistent in the quickly changing conditions. Sun would come out and mirage would be terrible and it would get really hot. Then clouds would roll over and wind would pick up in a different direction, then it would completely die only to come back 3 minutes later. All in one string!

Next month will be a 3x1000 match.

 

[Bill Norris]

Very good. Sounds like it was doing it's job for you.

Did you chrono your load before the match at all?

 

[Fast14riot]

Very good. Sounds like it was doing it's job for you.

Did you chrono your load before the match at all?

No I did not. I went straight from the 100y charge test to the match. I'll have to run the numbers and see what it comes up with. I suspect around 2800 even.

 

[Bill Norris]

No I did not. I went straight from the 100y charge test to the match. I'll have to run the numbers and see what it comes up with. I suspect around 2800 even.

Yea, probably so. Do you have any room at the top for more powder or are you maxed out?

 

[Fast14riot]

Yea, probably so. Do have any room at the top for more powder or are you maxed out?

Still have some room but like this slower node with these bullets. The 140s like to be pushed pretty fast, but a nice easy recoil and not hammering the brass makes it really nice.

 

[46and2]

I just loaded some 140 Matchburners with n160. 44.5gr was about 95% capacity with my long throated chamber.
Will update.
45gr of H4350 shot very very well, hopefully n160 can best it.

 

[Bill Norris]

I just loaded some 140 Matchburners with n160. 44.5gr was about 95% capacity with my long throated chamber.
Will update.
45gr of H4350 shot very very well, hopefully n160 can best it.

I plan to try some N160 with 140s next and get a comparison between N555 and N160 and move away from H-4350 if possible.

 

[Fast14riot]

I did notice today that the recoil impulse of N555 is different than RL23. 23 had a longer pressure curve feel, more like a big push but hit harder. N555 seems to be a bit more snappy feeling, similar to a faster burning powder, but less of a hit to my shoulder. Same bullet, velocity, case, gun, and nearly the same charge weight (45.5gr RL23, 45.1gr N555).

Unsure if it's anything of consequence yet, but having shot the same firing system for many years, it stood out to me. Thats a back of the notebook entry, I guess.

 

[Fast14riot]

Anyone do any testing or more shooting recently? If my anniversary wasn't tomorrow I'd go get some chrono data, but otherwise I've got a 3x1000 on 5/12 I'm going to shoot with it. Hope I can get chrono data before then.

 

[46and2]

Anyone do any testing or more shooting recently? If my anniversary wasn't tomorrow I'd go get some chrono data, but otherwise I've got a 3x1000 on 5/12 I'm going to shoot with it. Hope I can get chrono data before then.

Just tell her you're going out to get flowers.

 

[Bill Norris]

Anyone do any testing or more shooting recently? If my anniversary wasn't tomorrow I'd go get some chrono data, but otherwise I've got a 3x1000 on 5/12 I'm going to shoot with it. Hope I can get chrono data before then.

Oh yea it will make u proud no doubt. Its a 260AI. LOL.

 

[Bc'z]

Anyone do any testing or more shooting recently? If my anniversary wasn't tomorrow I'd go get some chrono data, but otherwise I've got a 3x1000 on 5/12 I'm going to shoot with it. Hope I can get chrono data before then.

It's your anniversary too.
hell I took fishing rods on our honeymoon.

 

[Alex Wheeler]

260 Ackley is a pretty good round. I shot one when I first got into LR BR. Before the dasher took over. Back then my favorite bullet was the 140 amax. This was before the amp jacket. Those original amaxes were awesome. Norma MRP powder was top choice with RL22 right behind it. It was a popular round at Manatee at one time. For BR use they seemed to like the mid 2800s which was not a hot load.