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Nosler AccuBond Long Range Seating depth
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A client has asked me to test fire his new .280 Ackley Imp. with 168-gr ABLR bullets but has not provided enough to experiment with seating depth. Is there a consensus as to how much clearance (jump) there should be to get optimal results with ABLR bullts? Thanks.
 
Posts: 462 | Location: Fayetteville, GA | Registered: 12 August 2004Reply With Quote
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The only ABLR bullets I have used have been the 168 gr. in the 7mm Rem. Mag. (Remington M700). I used 0.030 inches as measured with the Hornady tool and a modified case.
 
Posts: 772 | Registered: 03 January 2004Reply With Quote
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As a rule of thumb, I use 10/1000 for everything but Barnes bullets.


Mike



What I have learned on AR, since 2001:
1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken.
2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps.
3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges.
4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down.
5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine.
6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle.
7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions.
8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA.
9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not.
10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact.
11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores.
12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence.
13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances.
 
Posts: 10040 | Location: Loving retirement in Boise, ID | Registered: 16 December 2003Reply With Quote
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Other than with monometal bullets, it is always best to assume that the least practical jump between ogive and lands will result in the best accuracy until proven otherwise. The "minimum jump" rule of thumb is probably correct with monometals, too, except for their tendency to exhibit pressure spikes if not relieved some bit from the lands.
 
Posts: 13207 | Location: Henly, TX, USA | Registered: 04 April 2001Reply With Quote
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In all my years I have not found the jump makes any difference, but gets the blame for a lot of inaccuracy without any reason other than so and so said so...I done a lot of testing mostly with the 7x57s and 8x57s and their ilk..For target shooting it may have some validity..if for no other reason that aha!! faint


Ray Atkinson
Atkinson Hunting Adventures
10 Ward Lane,
Filer, Idaho, 83328
208-731-4120

rayatkinsonhunting@gmail.com
 
Posts: 41730 | Location: Twin Falls, Idaho | Registered: 04 June 2000Reply With Quote
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Adjusting "jump" is a good way to tune a rifle to shoot the very best groups the rifle is capable of.
If your rifle is only capable of 1 to 1.5" groups at 100, then it probably won't make much difference in a hunting rifle.

Once the powder charge is determined, achieving the appropriate velocity with seating depth at around 20 thousandths off, THEN you can further tune by seating longer of deeper by about 5-10 thousandths difference between groups to find something which works the very best in YOUR rifle.
If you don't want to KNOW what works best or don't want to "waste" that much ammo and time at the range, then don't worry about it.

To say seating depth doesn't matter and makes no difference is just flat out wrong! Will it make enough difference to you? Only you and your rifle can decide that.

Love, Zeke
 
Posts: 2269 | Registered: 27 October 2011Reply With Quote
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....and YES, make sure they fit in the mag box BEFORE you go hunting. My brother learned this the hard way with 250 Sierras in a 340 Wby. He still killed a find bull with his single shot because the first shot is always the important shot!
 
Posts: 2269 | Registered: 27 October 2011Reply With Quote
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Sorry for the rebuttal, now back the the original question about LR accubonds.

I've only used 3 different calibers and weights,
142's in a 6.5 creedmoor, 150's in a 280 AI and 210's in my 300 RUM and they all seem to shoot best at about 10-15 thousandths off the lands. That's pretty close to the lands for a hunting rifle but plenty far so as to not ever get stuck.
This is all provided the magazine will hold them at that length.

Zeke
 
Posts: 2269 | Registered: 27 October 2011Reply With Quote
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Mr. Ferrell,

Tight chamber, no worries.

1. I did (2) 7X57 single shot experiments with bullet jump to the lands. I found no difference between deep seated and long seated rounds with the same charge, bullet (Nosler Partition), new brass, etc. Worth noting is the chambers in both rifles tested were tight with no slop.

2. I also tested my Gew 98 Mauser in .270 Winchester with a sloppy chamber and a deep throat using 1X fire-formed cases. Same brand/type bullet as above. Group size shrunk by about .25" at 100 yards with .050" jump when compared to bullets seated low in the case.


Life itself is a gift. Live it up if you can.
 
Posts: 5077 | Location: Near Hershey PA | Registered: 12 October 2012Reply With Quote
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quote:
Originally posted by custombolt:
Mr. Ferrell,

Tight chamber, no worries.

1. I did (2) 7X57 single shot experiments with bullet jump to the lands. I found no difference between deep seated and long seated rounds with the same charge, bullet (Nosler Partition), new brass, etc. Worth noting is the chambers in both rifles tested were tight with no slop.

2. I also tested my Gew 98 Mauser in .270 Winchester with a sloppy chamber and a deep throat using 1X fire-formed cases. Same brand/type bullet as above. Group size shrunk by about .25" at 100 yards with .050" jump when compared to bullets seated low in the case.




I have no doubt about your findings.

If you've played with lots of bullet shapes, you'll run into a few that are a bit more seating depth sensitivity. The LR Accubond is one of them which can benefit with a little seating depth experimentation.

If it made no difference with any old bullet, seat them wherever you want.

Granted, some rifles shoot such that it's difficult to tell if seating depth, neck turning, neck sizing, powder weighing etc really matters and the truth is that it really isn't evident in many rifles.

Most rifle can benefit from the above but perhaps to a different degree from the next rifle.

Zeke
 
Posts: 2269 | Registered: 27 October 2011Reply With Quote
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Thanks Zeke. My emphasis on small groups of half inch has softened a bit. A 1 inch group (100y.) that is dead center on the target is only 1/2 inch off the point of aim. Close enough.


Life itself is a gift. Live it up if you can.
 
Posts: 5077 | Location: Near Hershey PA | Registered: 12 October 2012Reply With Quote
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