260 AI load data

[mbeavers1]

Any other bullet style will work. N555 is the RL26 for this cartridge, it has the same unicorn hooves and fairy dust supplier.

So if I found an 8lb of n555, i should grab it? I assume i could run 143gr ELDX if the lighter solids dont work out? My 260 Terminator is a bit different (35deg shoulder vs 40) but very similar to 260 AI. Nervous to chunk out $400 for an 8lb not ever trying it....oh the world we live in

 

[WWP2012]

Of course. I did just find some N165. Any idea how that would compare? I have some Re23 and H4831sc so I think these are all going to be very similar burn rates.

I tried RE16, 23, 26, h4350 and 4831sc. H4350 was good but about 75 FPS slower than N555. 16 was about 50fps slower. Re26 got the 140 to 2950 before I ran out of case capacity. N555 pushed a 140 over 3000. When I dropped to the Barnes 127 LRX it shot tiny cloverleaf groups at 3130.

I've never tried N165.

Everything was shot thru a 26" lilja 3 groove and Magnetospeed.

 

[WWP2012]

So if I found an 8lb of n555, i should grab it? I assume i could run 143gr ELDX if the lighter solids dont work out? My 260 Terminator is a bit different (35deg shoulder vs 40) but very similar to 260 AI. Nervous to chunk out $400 for an 8lb not ever trying it....oh the world we live in

400 is Waay to much. I paid 160 and 190 for 8 pounders. I would just use h4350 in a drop tube if you have it.

 

[mbeavers1]

400 is Waay to much. I paid 160 and 190 for 8 pounders.

Yea, thats the problem now....pay or dont play. I have a bunch of h4350 and h4831sc but it looks like it falls between these. Just dont want to have a new fancy toy and nothing to shoot it with.

Thing is $400 is a lot but if it works, Im good for the whole barrel on a hunter, which means prob my life

Besides, powder valley (who doesnt gouge) sells for $289 + tax and hazmat so maybe not that bad

 

[Hawkeye Pierce]

Thanks, I thought you were shooting a 260ai. I'm working with 124g HH and Varget. Just wondered what others where getting out of it.

Yes I did. Unfortunately I have the RL- 26 i purchased in advance and went with Lapua scenar 139 gr. Have been very happy with load development so far. Keep an eye out for bolt swipe, i see that before any ejector marks or stiff bolt.

 

[WWP2012]

Yea, thats the problem now....pay or dont play. I have a bunch of h4350 and h4831sc but it looks like it falls between these. Just dont want to have a new fancy toy and nothing to shoot it with.

Thing is $400 is a lot but if it works, Im good for the whole barrel on a hunter, which means prob my life

Besides, powder valley (who doesnt gouge) sells for $289 + tax and hazmat so maybe not that bad

You will never get the 75fps worth out of that kinda cash. H4350, drop tube, and shoot it.

 

[mbeavers1]

You will never get the 75fps worth out of that kinda cash. H4350, drop tube, and shoot it.

What chg weights did you start with for the h4350 and n555?

 

[WWP2012]

Correction I have a 24" barrel on that rifle.

127g Barnes LRX 8" drop tube
N555 47.6 at 3149 FPS was max
H4350 47 at 3088 FPS was max

140g accubond
RL26 49 at 2930 was case capacity max compressed load
N555 46 at 2934 was max pressure
H4350 and RL 16 did not get saved when I cleaned up my bench but we're right there in the ballpark.

From a friend
He shot the Barnes Match maker 145 N555.
47g at 2959 FPS max load.


All of this data came from rifles that were deep throated to maximize case capacity. Just because it was ran in ours doesn't mean it will run in yours. Start low and work your way up.

 

[mbeavers1]

Correction I have a 24" barrel on that rifle.

127g Barnes LRX 8" drop tube
N555 47.6 at 3149 FPS was max
H4350 47 at 3088 FPS was max

140g accubond
RL26 49 at 2930 was case capacity max compressed load
N555 46 at 2934 was max pressure
H4350 and RL 16 did not get saved when I cleaned up my bench but we're right there in the ballpark.

From a friend
He shot the Barnes Match maker 145 N555.
47g at 2959 FPS max load.


All of this data came from rifles that were deep throated to maximize case capacity. Just because it was ran in ours doesn't mean it will run in yours. Start low and work your way up.

Awesome! Thanks so much! Mine will be throated long. Defensive Edge makes their own bottom metal to allow them to be run longer. Will definitely start both of them low, prob in the 45 range.

Do you know what your freebore is?

 

[WWP2012]

Awesome! Thanks so much! Mine will be throated long. Defensive Edge makes their own bottom metal to allow them to be run longer. Will definitely start both of them low, prob in the 45 range.

Do you know what your freebore is?

No, when I dropped everything at the gunsmith shop I gave them a LRX dummy round set to 2.950 OAL. Told them I wanted .050 free bore for this set up. That's exactly what I got back.

I'm on my second 260ai and learned all the lessons on the first one I had built. It was a expensive way to learn what not to do. Now that first one is just a fire forming barreled action.

 

[mbeavers1]

No, when I dropped everything at the gunsmith shop I gave them a LRX dummy round set to 2.950 OAL. Told them I wanted .050 free bore for this set up. That's exactly what I got back.

I'm on my second 260ai and learned all the lessons on the first one I had built. It was a expensive way to learn what not to do. Now that first one is just a fire forming barreled action.

This is my first of this flavor as well and they are not as well known so your insight is appreciated. The component shortage makes things worse for sure since I cant run to the LGS and grab a box of 140 elite hunters or really even the LRXs, though I havent looked hard for them yet. I have 100 124 Hammer Hunters and going to look at the Cutting Edge Maximus or Lasers too based on your challenges w the Hammers.

 

[WWP2012]

This is my first of this flavor as well and they are not as well known so your insight is appreciated. The component shortage makes things worse for sure since I cant run to the LGS and grab a box of 140 elite hunters or really even the LRXs, though I havent looked hard for them yet. I have 100 124 Hammer Hunters and going to look at the Cutting Edge Maximus or Lasers too based on your challenges w the Hammers.

The best results I have had for brass neck length is Lapua 243 brass. Once or twice fired is even better.

 

[mbeavers1]

The best results I have had for brass neck length is Lapua 243 brass. Once or twice fired is even better.

I bought 260 lapua...new. did i pick the worst?

 

[WWP2012]

I bought 260 lapua...new. did i pick the worst?

It will work, 243 just has a longer neck on it.