ABs vs LRABs a question

Razorbacker

Beginner
Mar 31, 2013
105
0
My build is heating up and I was going to have the throat cut to accommodate the 180 Berger loaded long but suddenly I start hearing about performance issues on game with the Berger. So now I've switched to LRAB. I have plenty of ABs on hand but no LRABs and cannot find any.

Thus my question, does the length of an AB= the length of a LRAB of the same grain weight?
Caliber is .284 if it matters.
Thanks
 
Just went into my cave & measured :wink:.
160gr. AB in 284 Cal is 1.411"
150gr. ABLR in 284 Cal is 1.393"
168gr. ABLR IN 284 Cal is 1.520"
I took a photo but I am sorry but I do not know how to post it :evil:.
Not sure if this helps.

Blessings,
Dan
 
wildgene":3uuihia0 said:
...go to the main Nosler website, it gives the length of each bullet...

I'm looking at the site gene but I'll be seating this where the beginning of the boat tail is even with the base of the neck. This maximizes powder capacity while avoiding the dreaded donut hole.
The pics on the site make it look like the boat tail is extra long and I couldn't find a measurement of the boat tail. If I had that I could closely estimate the COAL I'm looking for.
Sigh... I guess worst case scenario I could just tell Jerry to hang loose til I can get my grubby mitts on a LRAB or two.
Anyway thanks for everyone's input.
 
Keep in mind that Bergers typically like to "kiss" the lands and Accubonds like some breathing room. What cartridge are you chambering and what weight accubonds/LRABs are you needing. I bet between myself and some others, we could provide the measurements or even samples for you.

Scott
 
muleman":frxzo6ae said:
Keep in mind that Bergers typically like to "kiss" the lands and Accubonds like some breathing room. What cartridge are you chambering and what weight accubonds/LRABs are you needing. I bet between myself and some others, we could provide the measurements or even samples for you.

Scott

Yeah I know bonded bullets usually like a jump. in the Berger I was looking at 180 grn in the LRAB 175.
This is for a .280AI
 
Razorbacker":3ahm4444 said:
wildgene":3ahm4444 said:
...go to the main Nosler website, it gives the length of each bullet...

I'm looking at the site gene but I'll be seating this where the beginning of the boat tail is even with the base of the neck. This maximizes powder capacity while avoiding the dreaded donut hole.
The pics on the site make it look like the boat tail is extra long and I couldn't find a measurement of the boat tail. If I had that I could closely estimate the COAL I'm looking for.
Sigh... I guess worst case scenario I could just tell Jerry to hang loose til I can get my grubby mitts on a LRAB or two.
Anyway thanks for everyone's input.

...appears that the boat tail on the ABLR is about 18- 19% of the total bullet length (this is pretty consistent thru-out), your trimmed case length + 1.20" would put you w/i +/- 0.01" of where you want the bottom of the shank of the 160/ 175gr. ABLRs, +1.10 for the 150gr...
 
wildgene":8ab9j0xd said:
Razorbacker":8ab9j0xd said:
wildgene":8ab9j0xd said:
...go to the main Nosler website, it gives the length of each bullet...

I'm looking at the site gene but I'll be seating this where the beginning of the boat tail is even with the base of the neck. This maximizes powder capacity while avoiding the dreaded donut hole.
The pics on the site make it look like the boat tail is extra long and I couldn't find a measurement of the boat tail. If I had that I could closely estimate the COAL I'm looking for.
Sigh... I guess worst case scenario I could just tell Jerry to hang loose til I can get my grubby mitts on a LRAB or two.
Anyway thanks for everyone's input.

...appears that the boat tail on the ABLR is about 18- 19% of the total bullet length (this is pretty consistent thru-out), your trimmed case length + 1.20" would put you w/i +/- 0.01" of where you want the bottom of the shank of the 160/ 175gr. ABLRs, +1.10 for the 150gr...

Thanks man, I really appreciate you going to all that trouble for me but I just don't think I'd feel comfortable without an actual bullet. Teach wrecked his motorcycle this morning. He survived but he's pretty dinged up so I feel like I have a little more time.
 
Razorbacker,
Took some measurements for you. I happen to have those bullets and cartridge sitting out on my loading bench. I don't trust measurements to the tip(to much variance) so I measured both ways. I used a Hornady bullet comparator and rezeroed my micrometer.
150gr LRAB: 1.375" total length
.700" base to ogive
1.143" tip to top of boat tail ( reversed bullet in comparator)
That gives you a .232" boat tail and a .468" bearing surface.

168gr LRAB: 1.523" total length
.825" base to ogive
1.285" tip to top of boat tail
That gives you a .232" boat tail and bearing surface of .593"

175gr LRAB: 1.536" total length
.855" base to ogive
1.304" tip to top of boat tail
That gives you a .232 boat tail and a bearing surface of .623"
Here is a link to the SAMMI 280AI drawing:
http://www.saami.org/PubResources/CC_Dr ... proved.pdf

My 280AI is a standard SAMMI chamber and is 2.755 to the lands. The 150 gr LRAB loaded to 3.384" is .046" off the lands and still retains .284" of bearing surface in the neck(with a freshly trimmed case at 2.525"). I won't be able to touch the lands or even chase them very far. Luckily the ABs like a little room, the regular ABs have all been between .03 and .05 off to find the sweet spot. The 168gr ABLR fits well. Loaded to an OAL of 3.433 I'm .02" off the lands and only have about .030"case impingement of bearing surface beyond the neck. I can move that 168 up or back and not lose much in case capacity. If you throat for the heavies I think you lose the 150gr.. The 175gr isn't much different from the 168gr. Loaded at 3.417" the 75gr.is .02" off the lands and has .074" impingement of bearing surface into the shoulder. If I wanted to shoot the Bergers I'd push'em up towards the lands and I'd still have good bearing in the neck and less case impingement. I've compared the ballistics of all the .284 LRABs and all three fall into the 1635-1705fps, 970-1044lbs energy and 23-26 MOA drop at 1k yards. I'm going to shoot the one that performs best out of my rifle. Let the testing begin!
Scott
P.S. Shoot me a pm with your mailing address and I'll mail you a couple of each weight.
 
Scott,

Thanks for all that. I too chose the SAAMI specs. I've read your post a few times but I'm just too tired tonight to wrap my mind around it all. But I will save it in case I can't find any LRABs. I'm glad you brought up that thing about losing the 150s I've had it in the back of my mind that I don't want to lose versatility, both in weight and also in types and brands of bullets.
My wife will be using this too so I will have 2 loads to work up.
Thanks again buddy.
 
Hi Scott, thank you for the information. Do you think that I maybe wasting my time with the 150gr ABLRs as I have the 1-9 twist in my 280AI it is also chambered to SAAMI specs.
I have a two boxes of 150gr. I also have 2 boxes of the 168gr. for my rifle.

Blessings,
Dan
 
Not at all Dan. I've found some ABs to be accurate with a .50" jump. I've also shot Weatherbys that have very long throats and were quite accurate. The accuracy node just might be small.
Scott
 
muleman":1qebc26v said:
Razorbacker,
Took some measurements for you. I happen to have those bullets and cartridge sitting out on my loading bench. I don't trust measurements to the tip(to much variance) so I measured both ways. I used a Hornady bullet comparator and rezeroed my micrometer.
150gr LRAB: 1.375" total length
.700" base to ogive
1.143" tip to top of boat tail ( reversed bullet in comparator)
That gives you a .232" boat tail and a .468" bearing surface.

168gr LRAB: 1.523" total length
.825" base to ogive
1.285" tip to top of boat tail
That gives you a .232" boat tail and bearing surface of .593"

175gr LRAB: 1.536" total length
.855" base to ogive
1.304" tip to top of boat tail
That gives you a .232 boat tail and a bearing surface of .623"
Here is a link to the SAMMI 280AI drawing:
http://www.saami.org/PubResources/CC_Dr ... proved.pdf

My 280AI is a standard SAMMI chamber and is 2.755 to the lands. The 150 gr LRAB loaded to 3.384" is .046" off the lands and still retains .284" of bearing surface in the neck(with a freshly trimmed case at 2.525"). I won't be able to touch the lands or even chase them very far. Luckily the ABs like a little room, the regular ABs have all been between .03 and .05 off to find the sweet spot. The 168gr ABLR fits well. Loaded to an OAL of 3.433 I'm .02" off the lands and only have about .030"case impingement of bearing surface beyond the neck. I can move that 168 up or back and not lose much in case capacity. If you throat for the heavies I think you lose the 150gr.. The 175gr isn't much different from the 168gr. Loaded at 3.417" the 75gr.is .02" off the lands and has .074" impingement of bearing surface into the shoulder. If I wanted to shoot the Bergers I'd push'em up towards the lands and I'd still have good bearing in the neck and less case impingement. I've compared the ballistics of all the .284 LRABs and all three fall into the 1635-1705fps, 970-1044lbs energy and 23-26 MOA drop at 1k yards. I'm going to shoot the one that performs best out of my rifle. Let the testing begin!
Scott
P.S. Shoot me a pm with your mailing address and I'll mail you a couple of each weight.

PM sent and thank you
 
sask boy":2lpeiv6x said:
Hi Scott, thank you for the information. Do you think that I maybe wasting my time with the 150gr ABLRs as I have the 1-9 twist in my 280AI it is also chambered to SAAMI specs.
I have a two boxes of 150gr. I also have 2 boxes of the 168gr. for my rifle.

Blessings,
Dan


Nope 175's stabilized in my 1-9" throated long. 150's will be just fine.
 
Tracy,
A couple of each weight sent out to you today. Nosler is starting production back up for the LRABs. They're starting with the 190 .308s.
Scott
 
muleman":2qemmk7i said:
Tracy,
A couple of each weight sent out to you today. Nosler is starting production back up for the LRABs. They're starting with the 190 .308s.
Scott

That's great news! I would imagine with the popularity of .284s they shouldn't be far behind.
 
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