Nosler ABLR Jump

[mwkelso]

I'm curious to know what distance of jump is successful with this bullet, specifically the 150gr .270.
I shot a seating depth test today up to 0.060" off the lands and wasn't too terribly impressed. The only two groups worth mentioning was the 0.030" that shot just barely over a minute, and the 0.060" that shot two through the same hole, but then had a flier 1-1/2 minutes high.
Brass is RP 3x fired
Primer- CCI200
Powder- 55gr H4831
Temp- 77 farenheight at 2250'

 

[Dmagna]

Barrel twist?

 

[mwkelso]

Barrel twist?

1:10"

 

[aushunter1]

Well the subject of seating depth & also the affects of seating depth & throat errosion has been covered quite a lot on here in some of these threads-

Test Seating Depth With Each Powder?

When you try another powder with a bullet you have been using, do you go through the complete seating depth process? Or have you found that the seating depth remains fairly consistent independent of powder? With powder availability issues like never before, I find myself having to make some...

www.longrangehunting.com

Bullet jump vs throat erosion

There has been a considerable amount of discussion recently since the PRB series about throat erosion and jump. I've been working up load for a new GAP 6.5 SAUM and for the most part enjoying the journey trying out some of the PRB ideas. I have had mixed success with groups ranging from 0.3 MOA...

www.longrangehunting.com

There is the Berger method you could look at as well as a theory even though its a different projectile.

I have my own method as many do, I start all my reloading @10 thou, find the node(s) do another test changing the CBTO to 5thou, 15thou & 20thou, find the best from that then if it needs tweeking again I will do some .1gr powder increment changes from that charge.

Ive never had to seat any deeper than 20thou before getting a result.

Also I dont shoot 3 shot groups, I shoot 5 for the reason you outlined in the comment "0.060 that shot two through the same hole, but then had a flier 1-1/2 minutes high", if you shot a 4th & a 5th it would be more evedent if it is a decent node.
I used to shoot 3 then found myself having to re shoot same charges again because of the same reason!

I have never used any Alliant powder but imo you have the right powder for the 270 in the H4831 although I use the SC version.

 

[Plinker147]

In 3 different guns sweet spot was around .050. LRAB have been a little harder to find there sweet spot than the regular accubond or other bullets. I think there construction has a lot to do with it.

 

[Muddyboots]

First: lots of threads on seating depth of the ABLR on LRH. Search and you will have reading for days on it. I have tried the normal seating depth trials off the lands and have found that I ended up closer to what Nosler recommends than what I normally shoot with other bullets including the BT's or AB's.

Nosler states:
TECHNICAL NOTE
*When loading the AccuBond®-LR bullet, Nosler ballisticians have found that loading to the maximum SAAMI cartridge overall length tends to provide best accuracy.
Link: Nosler ABLR Page

The most accurate load in my .270W is slightly longer than SAAMI using RL26 so I think these bullets can be perplexing if you stay with the std 0.010-0.050 off as a starting point. When I started at SAAMI 3.340 and went longer using similar concept then my groups got much better. The same thing occurred with my 300WM with 190 ABLR but yet I am 0.010 off with the 200AB that shoots lights out close.

So you may want to try starting at SAAMI as one possible load trial instead of the usual setting off the lands. Some bullets just need a jump (leap?) to maximize accuracy.

 

[Troutslayer2]

.075 and that's not because of the magazine length- that's how far I jump 168s in my 280.

 

[backwoods83]

I would first try the method I use for Berger vlds in weatherby chambers, that's just seating the bullet where it belongs (bottom of the bearing surface at the bottom of the neck) this method allows you to use the entire neck to guide the bullet. Best to have minimal runout using this method. Once you get decent results, switch to 59-60grns of RL26 and wake that thing up a little.

 

[mwkelso]

@aushunter1
I think you're right about shooting 5-shot groups. I'm wondering now if the flier on 0.060" was just that, a flier by my error. I'll repeat the test based on the 0.030" and 0.060" including those jumps and 0.005" both directions in 5-shot groups.

I had 1-1/2min flier stuck on my mind for some reason, looks like it was just over 1min. Grid lines are 1", test was at 100yds.

@Muddyboots
Definitely going to be a major "leap" if I go to spec! SAAMI calls for 3.340", my longest jump on this test was coal 3.379". Spec will give me a 0.099" jump.

 

[mwkelso]

I would first try the method I use for Berger vlds in weatherby chambers, that's just seating the bullet where it belongs (bottom of the bearing surface at the bottom of the neck) this method allows you to use the entire neck to guide the bullet. Best to have minimal runout using this method. Once you get decent results, switch to 59-60grns of RL26 and wake that thing up a little.

I'll give this a try as well. It's a Vanguard that it's being shot out of. Very deep chamber...

I ran RL23 in a 30-06 not too long ago with the ABLR's, but was having capacity issues. Is RL26 anything like 23 in needing a greater case capacity to avoid major compression?

 

[aushunter1]

@aushunter1
I think you're right about shooting 5-shot groups. I'm wondering now if the flier on 0.060" was just that, a flier by my error. I'll repeat the test based on the 0.030" and 0.060" including those jumps and 0.005" both directions in 5-shot groups.

I had 1-1/2min flier stuck on my mind for some reason, looks like it was just over 1min. Grid lines are 1", test was at 100yds.

@Muddyboots
Definitely going to be a major "leap" if I go to spec! SAAMI calls for 3.340", my longest jump on this test was coal 3.379". Spec will give me a 0.099" jump.View attachment 203171

Yes like I was saying, 3 shots makes the result inconclusive on the .60 & you end up doubting the result so you end up re testing & burning more powder/consumables.
Also IF for instance you had a good 4 shot group & 1 flyer then I would be looking at why......?
Could this be accredited to inconsistant neck tension through case hardening or some other factor??

So just curious, this is the results for 55gr H4831 but where are the other results for the incrimental powder charges??

I also think changing depth by .10 is to much, I change mine in .05 incrimenents.

I'll give this a try as well. It's a Vanguard that it's being shot out of. Very deep chamber...

I ran RL23 in a 30-06 not too long ago with the ABLR's, but was having capacity issues. Is RL26 anything like 23 in needing a greater case capacity to avoid major compression?

I just looked at the RL26 data for 270W & yes its faster but then again its up to another 5.1gr more powder @ 60.2 to 60.8gr, that doesnt look right to me??

 

[mwkelso]

Yes like I was saying, 3 shots makes the result inconclusive on the .60 & you end up doubting the result so you end up re testing & burning more powder/consumables.
Also IF for instance you had a good 4 shot group & 1 flyer then I would be looking at why......?
Could this be accredited to inconsistant neck tension through case hardening or some other factor??

So just curious, this is the results for 55gr H4831 but where are the other results for the incrimental powder charges??

I also think changing depth by .10 is to much, I change mine in .05 incrimenents.



I just looked at the RL26 data for 270W & yes its faster but then again its up to another 5.1gr more powder @ 60.2 to 60.8gr, that doesnt look right to me??

The RL26 data makes sense to me... it's closest burn rate listed in the Nosler 8th is MagPro ranging 57.5-61.5gr. RL26 appears to be slightly slower than MagPro according to the burn chart...

I will find my powder charge results...we are in the middle of rearranging the house, so I am sure they are somewhere around here...

 

[mwkelso]

@aushunter1

I just realized my fatal flaw
I had worked seating depth prior on this rifle, but was too cheap to buy a comparator and properly obtained max cbto. I was chasing my tail with inadequate results because I was jamming 0.020" thinking that was 0. I loaded the next test (this one) without even considering the starting load.
I just restarted a seating depth test on a max load

For some, probably not a big deal. No pressure signs, whatever. But my process is to start with depth before charge...

 

[backwoods83]

I'll give this a try as well. It's a Vanguard that it's being shot out of. Very deep chamber...

I ran RL23 in a 30-06 not too long ago with the ABLR's, but was having capacity issues. Is RL26 anything like 23 in needing a greater case capacity to avoid major compression?

No, RL26 is very dense, you can fit 63grns easily in Nosler brass.